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Astronomy &Astrophysics manuscript no. Spurny_Taurids c
ESO 2017
May 25, 2017
Discovery of a new branch of the Taurid meteoroid stream as a real
source of potentially hazardous bodies
P. Spurný1, J. Boroviˇ
cka1, H. Mucke2, and J. Svoreˇ
n3
1Astronomical Institute of the Czech Academy of Sciences, CZ-25165 Ondˇ
rejov, Czech Republic
e-mail: pavel.spurny@asu.cas.cz
2Astronomisches Büro, 1230 Wien, Austria
3Astronomical Institute of the Slovak Academy of Sciences, SK-05960 Tatranská Lomnica, Slovak Republic
Received March 14, 2017; accepted May 1, 2017
ABSTRACT
Taurid meteor shower produces prolonged but usually low activity every October and November. In some years, however, the activity
is significantly enhanced. Previous studies based on long-term activity statistics concluded that the enhancement is caused by a swarm
of meteoroids locked in 7:2 resonance with Jupiter. Here we present precise data on 144 Taurid fireballs observed by new digital
cameras of the European Fireball Network in the enhanced activity year 2015. Orbits of 113 fireballs show common characteristics
and form together a well defined orbital structure, which we call new branch and which was evidently responsible for the enhanced
activity. This new branch is part of Southern Taurids and was encountered by the Earth between October 25 and November 17. We
found that this branch is characterized by longitudes of perihelia lying between 155.9 – 160◦and latitudes of perihelia between 4.2 –
5.7◦. Semimajor axes are between 2.23 – 2.28 AU and indeed overlap with the 7:2 resonance. Eccentricities are in wide range 0.80 –
0.90. The most eccentric orbits with lowest perihelion distances were encountered at the beginning of the activity period. The orbits
form a concentric ring in the inner solar system. The masses of the observed meteoroids were in a wide range from 0.1 gram to more
than 1000 kg. We found that all meteoroids larger than 300 grams were very fragile (type IIIB), while those smaller than 30 grams
were much more compact (mostly of type II and some of them even type I). Based on orbital characteristics, we argue that asteroids
2015 TX24 and 2005 UR, both of diameters 200 – 300 meters, are direct members of the new branch. It is therefore very likely
that the new branch contains also numerous still not discovered objects of decameter or even larger size. Since asteroids of sizes of
tens to hundreds meters pose a treat to the ground even if they are intrinsically weak, impact hazard increases significantly when the
Earth encounters the Taurid new branch every few years. Further studies leading to better description of this real source of potentially
hazardous objects, which can be large enough to cause significant regional or even continental damage on the Earth, are therefore
extremely important.
Key words. Meteors, Meteoroids – asteroids – comets: 2P/Encke – Earth
1. Introduction
The Taurid meteoroid stream is one of the most studied mete-
oroid streams. This stream produces at least four meteor showers
on Earth: the Northern and Southern Taurids, both active from
end of September until December; the Daytime ζ-Perseids, ac-
tive from end of May to the beginning of July; and the Daytime
β-Taurids, active in June and the first half of July (Jenniskens
2006). Other showers may be also related to the Taurid stream,
namely the Piscids in September, χ-Orionids in December, and
Daytime May Arietids in May (Jenniskens 2006). Since the work
of Whipple (1940), the short period comet 2P/Encke has been
considered the most probable parent body of the Taurid stream.
It was, nevertheless, proposed that 2P/Encke is just a fragment of
a much larger comet, which was disrupted 103–104years ago and
formed the whole Taurid complex including a number of aster-
oids (Clube & Napier 1984; Napier 2010). As more and more as-
teroids were being discovered over time, the number of asteroids
proposed by various authors as members of the Taurid complex
increased (e.g., Asher et al. 1993; Babadzhanov 2001; Porubˇ
can
et al. 2006; Babadzhanov et al. 2008; Olech et al. 2016). The
problem is that the Taurid stream is very extended and the low-
inclination short-period Taurid orbits are very common for near-
Earth asteroids. Many proposed associations can be therefore
just random coincidences. Indeed, the spectra of six large as-
teroids proposed as members of the Taurid complex showed that
five of them are inconsistent with a cometary origin (Popescu et
al. 2014).
The activity of Taurids is prolonged but usually of low level.
In some years, however, the activity is enhanced, especially in
terms of large numbers of bright meteors (fireballs). Asher &
Clube (1993) proposed that there is a resonant swarm of mete-
oroids trapped in the 7:2 resonance with Jupiter. The expected
extent of the swarm was ±30 – 40◦in mean anomaly. Asher &
Izumi (1998) showed that enhanced Taurid activity indeed oc-
curred in the years when the center of the swarm was less than
40◦in mean anomaly from the Earth at the beginning of Novem-
ber (the date of Taurid maximum). Asher & Clube (1993) pre-
dicted that future encounters would occur in 1995, 1998, 2005,
and 2008. In 1995, enhanced Taurid activity was observed by
the European Fireball Network (EN) when the rate of registered
Taurid fireballs was noticeably higher than is usual for the EN
at that time of year (Spurný 1996). Apart from regular Southern
and Northern Taurids, five fireballs observed during the last week
of October 1995 had distinct but very similar orbits. The radiants
lay near the regular southern Taurid radiant, but the initial veloc-
ities were larger (Vg=33.1±0.3 km s−1). As a result these orbits
Article number, page 1 of 24
arXiv:1705.08633v1 [astro-ph.EP] 24 May 2017
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Fig. 1. Stations of the fireball network located in Czech Republic, Slovakia and Austria where DAFO are placed (status November 2015)
had significantly larger semimajor axes (a=2.52±0.08 AU), ec-
centricities (e=0.905±0.004) and inclinations (i=6.2◦±0.4◦),
and smaller perihelion distances (q=0.241±0.009 AU) than the
regular Southern Taurid orbit. The existence of this well-defined
cluster of similar Taurid meteoroids very probably means that
the enhanced activity in 1995 was caused by a new relatively
compact subsystem of the Taurid complex close to the South-
ern Taurids. As mentioned in Jenniskens (2006), this observation
identifies, for the first time, a meteor outburst associated with the
Taurid shower, and by implication the Earth crossing a relatively
young dust trail. The 1995 enhanced activity was also confirmed
by visual observations (Dubietis & Arlt 2007), both in terms of
increased overall activity and increased percentage of fireballs
in the period from October 23 to November 15 (McBeath 1999).
Similarly Johannink & Miskotte (2006), also from visual obser-
vations, confirmed increased Taurid activity in 1998 and 2005
and suggested that the Southern Taurids are responsible for the
higher activity in resonance years.
Shiba (2016) analyzed Taurid video observations from 2007
to 2015, including swarm encounter years 2008, 2012, and 2015
(see the webpage of D. Asher1for swarm encounter predictions).
He confirmed that the enhanced activity is exclusively due to
Southern Taurids. Shiba also studied the dependency of orbital
elements on time and found that not only the mean orbital pe-
riod of swarm meteoroids but also that of Northern Taurids cor-
respond to the 7:2 resonance with Jupiter. The eccentricity was
found to decrease and perihelion distance to increase with time.
The work of Shiba work is statistical in nature, involving
thousands of meteors but with large individual uncertainties.
Here we present precise data on 144 Taurid fireballs observed by
new digital cameras of the European Fireball Network in 2015.
The description of the observational system, examples of the
data, and demonstration of their precision are given in Sect. 2
and 3. In Sect. 4 we show that the enhanced activity in 2015 was
1http://star.arm.ac.uk/dja/taurid/swarmyears.html
caused by a well-defined branch of Taurid meteoroids. We con-
centrate our study on orbital elements and only briefly discuss
the physical properties of the meteoroids. In Sect. 5 we show that
several known asteroids also belong to the branch, which caused
the 2015 activity. The implications of our work are discussed in
Sect. 6.
2. Observational techniques and data acquisition
The data reported here were obtained by the European Fireball
Network (EN). The core of the network, located in the Czech Re-
public, has been modernized several times (Spurný et al. 2007).
But the last significant improvement has been realized during
the last three years when a completely new instrument, the high-
resolution digital autonomous fireball observatory (DAFO), was
developed and gradually installed on the stations of the fireball
network between November 2013 and September 2015. These
new all-sky digital cameras are working alongside the older
analog (using photographic films) autonomous all-sky cameras
(AFO) on the majority of Czech stations but this older system
based on AFOs is gradually being decommissioned. At the end
of 2015 the DAFOs were installed on 13 stations around the
Czech Republic (Šindelová and Kocelovice stations are com-
pletely new and were built in mid-2015). Apart from the Czech
territory, two DAFOs were installed on the already working sta-
tions in Slovakia and Austria, respectively. The first DAFO was
installed at the observatory of the Slovak Academy of Sciences
in Tatranská Lomnica, where one AFO also remains in full oper-
ation, and the second, installed at the Waldviertel Observatory in
Martinsberg (Austria), substituted the previous AFO system in
September 2015. This core of the EN as schematically shown in
Figure 1 also cooperates with other parts and systems located in
neighboring European countries but data used in this study are
solely acquired by the stations based on the DAFO (vast majority
of used records) and AFO cameras as described above.
Article number, page 2 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Fig. 2. Detailed views of the EN051115_231201 Taurid fireball recorded by DAFOs at the stations 126 Martinsberg, 102 Kunžak, 107 Kuchaˇ
rovice,
and 114 ˇ
Cervená hora. All-sky images from these stations were used for the analysis.
The imaging part of the DAFO system is comprised of a full
frame Canon 6D digital camera and a Sigma fish-eye lens (8
mm f/3.5) equipped with an electronic LCD shutter for speed
determination. In standard regime 16 interruptions and 35 s long
exposure are used. To avoid possible loss of data during read-
ing time of the CMOS sensor, we use two identical imaging sets,
which work in alternation mode with 5 second overlap. The older
AFOs analog imaging part is comprised of a Zeiss Distagon fish-
eye lens (30 mm f/3.5). Large format panchromatic sheet films
(9 x 12 cm, Ilford FP4) are used. The diameter of the sky on
the image is 8 cm and usually one exposure is taken per night.
Mechanical shutter with 15 interruptions per second is used. The
sensitivity limit is −4 magnitude for AFO (about 2−3 mag lower
around the full Moon period) and −2 magnitude for DAFO (with
lower dependence on lunar phase). Apart from the imaging part,
each DAFO and AFO is equipped with an all-sky radiometer
with time resolution of 5000 samples per second and with sim-
ilar sensitivity limit (in the moonless nights) like the imaging
system but with much higher dynamic range. These radiometers
serve several purposes, such as the real-time detection of fire-
balls, their exact absolute timing (system time is continuously
corrected by the PPS pulse of the GPS), recording of detailed
light curve profiles, and for precise photometry, especially for
brighter events when digital images become saturated as shown
in one example later.
The data presented in this study were obtained almost com-
pletely by the new digital autonomous system (DAFO). Thanks
to their higher sensitivity, fireball observations from DAFO con-
tain more information especially in the beginning and terminal
parts of the luminous trajectory in comparison with AFO. An-
other important advantage of DAFO is the ability to work dur-
ing periods when it is not completely dark (twilight periods) and
not completely clear (partly cloudy sky) as well. The data from
the new digital system allow us to reliably determine all basic
parameters of sufficiently bright fireballs up to the distance of
300 km from the stations (for special cases even up to 600 km).
It means that with the current number and displacement of sta-
tions (see Figure 1) we effectively cover territory of roughly 3
million square kilometers at least, i.e., a large part of Central Eu-
rope. All the advantages mentioned above significantly increased
the efficiency of our observations; and in direct comparison with
the efficiency of the previous analog AFO system the number of
recorded fireballs increased at least three times. When we com-
bine this increased efficiency with improved analysis techniques,
which we developed and gradually improved especially in the
last several years, we obtain results than were not reached by
any previous observing system used within the EN.
3. Data reduction
As described above, our fully automated instruments DAFO and
AFO provide us with two kinds of data: all-sky photographic
records and high-resolution radiometric light curves. For the
complete analysis of every fireball that was recorded from at
least two stations (the vast majority of the presented fireballs
were recorded from more than two stations) we use our own pro-
cedures, methods and analysis software. All-sky images taken
in the raw format are measured by the FishScan application,
which allows semiautomatic measurement of positions, speed,
and photometry. Usually the photometry from digital images is
reliable up to −8 apparent magnitude, brighter events start to be
saturated after reaching this brightness. However, thanks to the
Article number, page 3 of 24
A&A proofs: manuscript no. Spurny_Taurids
Fig. 3. Lateral deviations of all measured points on the fireball luminous
path from the available records. The Y-axis scale is highly enlarged and
one standard deviation for any point on the fireball trajectory is only 7
m.
Fig. 4. Radiometric light curves of the EN051115_231201 fireball taken
by fast photometers (5000 samples/s) at Kunžak (blue) and ˇ
Cervená
hora (red) stations. These apparent (not corrected for distance) light
curves taken from places185 km apart demonstrate perfect compliance
of both records; small differences in heights of individual peaks are
caused by different distances to the fireball.
high dynamic range of radiometers, which are incorporated in
each DAFO and AFO, we are able to obtain precise photometry
also for much brighter fireballs, even for superbolides as will be
shown later. We can calibrate radiometric records using not satu-
rated parts of the light curve obtained from photographic records.
Our whole procedure is demonstrated on the example below.
3.1. EN051115_231201 Taurid fireball: Example of data
analysis
The Taurid fireball of November 5, 2015, 23:12:01 UT, was
recorded photographically and photoelectrically at seven stations
in our network. For a complete analysis of this fireball, we chose
records taken from four stations that were close to its atmo-
spheric trajectory and were sufficient for reliable determination
of all parameters describing atmospheric trajectory, dynamics,
photometry, and heliocentric orbit of this fireball. A selection
of all-sky images of the fireball taken at individual stations are
shown in Figure 2.
The first step after measurement of all four digital images
and their astrometric reduction is computation of the atmo-
spheric luminous trajectory. We use two different methods de-
scribed in Ceplecha (1987): the so-called plane method, and in
Fig. 5. Photographic and radiometric light curves of the
EN051115_231201 fireball in absolute magnitudes.
Boroviˇ
cka (1990), the so-called least-squares method. A first in-
dependent check of the results is that the values describing the
atmospheric trajectory obtained from these two methods turn out
to be the same within the uncertainties. Lateral deviations of all
measured points from the resulting atmospheric trajectory (zero
line) are shown in Figure 3. This plot illustrates the high reliabil-
ity of the astrometric solution. The spread of the measured points
from individual stations is random and the standard deviation is
only 7 m. In this context it is also important to mention how far
each station (camera) was from the fireball. Exact distances of
the beginning and terminal points R(B÷E)for each station were as
follows:
R(B÷E)(107) =141.8÷92.7 km;
R(B÷E)(126) =149.1÷119.5 km;
R(B÷E)(102) =176.6÷143.3 km;
R(B÷E)(114) =221.5÷189.8 km.
This example nicely illustrates that our records and meth-
ods provide us with a precision of the atmospheric trajectory de-
termination of about 10 m for fireballs that are still about 200
km away the stations. Most of the Taurids in this study, espe-
cially the fainter ones, were below or around this distance, and
only several of the brightest cases were at much larger distances
from the stations. The most distant Taurid was the superbolide
EN311015_180520, which was also recorded by the cameras at
distances of up to 630 km (stations that were used for analysis).
Data precision for such a distant and difficult to measure case is
about 140 meters, which is still good. The precision is crucial
not only for the determination of the position of the trajectory
in the atmosphere, but also for the determination of the direc-
tion of flight of the meteoroid, in other words, the position of the
apparent radiant, which is important for determination of the he-
liocentric orbit of the meteoroid. The coordinates of the apparent
radiant for this particular fireball were
αapp =54.947◦±0.007◦,δapp =16.196◦±0.004◦.
When computing the local azimuth and slope of the trajec-
tory, we took into account the curvature of bolide trajectory due
to gravity, which can be significant for longer fireballs with very
precise data. For the EN051115_231201 it is only 0.02◦.
The second step is the determination of the velocity of the
fireball. The data in this study are so good that it enabled us
to use the method described in Ceplecha et al. (1993) for the
Article number, page 4 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
vast majority of fireballs. Successful application of this model
is very sensitive to the quality of the lengths for each individ-
ual measured velocity point corresponding to a single shutter
break. This rigorous physical model provides the speed at any
point on the trajectory but for the presented study, which is fo-
cused on the orbital analysis, the initial velocity is the most
important. For the sample fireball we obtained a four parame-
ter (non-fragmenting) solution including initial velocity for each
station and all solutions were very similar. Nevertheless for the
final dynamic solution and initial velocity determination, not
only for this particular case but for all cases in this study, we
used a slightly different approach. We put all measured shutter
breaks from all used images together (timescales on all DAFOs
are correlated) and we applied the Ceplecha method on this uni-
fied data set. This approach significantly increases reliability of
the resulted dynamic solution. It is useful especially for shorter
fireballs such as Taurids because they are moderately fast mete-
oroids of cometary origin (i.e., relatively fragile) and the number
of measured breaks on one image can be limited. Therefore, ev-
ery independent measurement can be very useful in obtaining a
reliable value of the initial velocity. Moreover, for some fireballs
the non-fragmenting solution applied to the whole trajectory was
not adequate and we had to omit the terminal part of the fireball
to obtain a realistic value of the initial velocity. This was also
the case of the sample Taurid fireball EN051115_231201 as can
be seen for example in Figure 4 where several bright flares cor-
responding to fragmentation events are clearly visible. The re-
sulting value of initial velocity of the EN051115_231201 Taurid
fireball is 31.221 ±0.037 km s−1.
The next step in the analysis of the available records is the ex-
act photometry of the fireball. We have two different data types,
those from photographic records and radiometers, from which
we can determine the brightness of the fireball and its initial
mass based on photometry. As mentioned above, we measure
digital images in 14-bit raw format. We found that this limited
dynamic range of the used CMOS sensor is sufficient for fire-
balls with apparent magnitude up to about −8. Above this limit
the measured signal starts to be saturated. As shown in Table 5,
which contains basic physical data of the presented Taurids, this
method can be reliably used for about 75% of all cases. The re-
maining 25% of presented cases are such bright fireballs that
their digital images are partly or even almost completely sat-
urated. For such fireballs we have different methods to describe
their brightness. One solution to this problem is the use of simul-
taneous photographic images taken by the AFO on the film. The
response of the film emulsion is logarithmic, which means that
the photographic film has much higher dynamic range; we use
Ilford FP4 panchromatic films with sensitivity 125 ASA. This is
a quite straightforward method and we used it in few cases, but
a still much more appropriate and accurate way is the use of the
light curves taken by the radiometers, which are in our cameras
and still have much higher dynamic range. The apparent (i.e.,
not corrected for distance) high-resolution (5000 samples/s) ra-
diometric light curves of the EN051115_231201 fireball taken
by radiometers at Kunžak (blue) and ˇ
Cervená hora (red) stations
are shown in Figure 4. The close agreement between the dif-
ferent records, a testament to the high precision of the data, is
evident. As for other two closer stations to the fireball, the ra-
diometric light curves have exactly the same profile and could
be used for fireball photometry. However, we cannot use radio-
metric light curves directly because individual radiometers have
different sensitivity and are not calibrated to obtain absolute pho-
tometry. For the purpose of calibrating these records we combine
photometry from both methods. We measure the meteor signal
on the digital image and for calibration we use that part of the
photographic image, which is not saturated and at the same time
well above the noise of the measured signal from both the pho-
tographic records and corresponding radiometric records. This
is usually somewhere in the interval between −4 and −7 magni-
tude. However, we have to relate the timescale of the photograph
to the absolute timescale of the radiometer. For this purpose we
use time marks (breaks of double length) made by the electronic
shutter along the luminous path of the recorded fireball on the be-
ginning of each second. This defines the exact absolute time of
this measured point, which can be simply identified with the cor-
responding point on the radiometric light curve. Both radiome-
ter and electronic shutter are continuously corrected by the PPS
pulse of the GPS so the absolute timing of both records is given
with high precision.
The result of this procedure is illustrated on Figure 5 in
which photographic and radiometric light curves from all used
stations in absolute magnitudes are plotted. The first evident re-
sult is that, especially for shorter and faster fireballs containing
bright and short significant flares, the photographic photome-
try cannot correctly describe the shape of the light curve be-
cause of the low time resolution. The electronic shutter, on the
other hand, has a resolution of 16 interruptions per second with
the same length for the on/offstate. This means that blind time
lasts exactly 0.03125 seconds and it is sometimes longer than
the duration of a flare or at least its brightest part. As can be
seen in Figure 4 and Figure 5, this is exactly the case of fireball
EN051115_231201, where most of the light is contained within
five distinct and quite short flares that are only partly recorded
(or even missing) on the image. Another aspect that is evident
in Figure 5 is the saturation of the photographic records. The
absolute photographic photometry profile (brightest parts of the
light curves) is, unlike the radiometric photometry, quite differ-
ent for individual stations. However it confirms the saturation
effect because stations, which are more distant from the fireball
give higher absolute maximum brightness. It means that these
records are not as saturated as the records from closer stations.
The last aspect, which is worth mentioning in connection with
the photometry shown in Figure 5, is that for correct calibration
of radiometric light curves it is much better to use the radiomet-
ric record and photographic image from the closest station where
the signal-to-noise ratio is the most favorable. This is valid es-
pecially for the fireballs as in the case described here, when the
increase of the brightness is very steep and the suitable (not sat-
urated) interval of magnitudes is very short.
A general conclusion is that the high-resolution radiometric
records are crucial for correct recovery of the photometry of all
brighter fireballs, especially those that contain distinct flares. We
note that the photometry based on radiometric light curves was
determined for about 90% of analyzed Taurids in this study.
As explained above, apart from the precise photometry of the
recorded fireballs, radiometric records provide us with a very ac-
curate absolute time of each event. This important parameter is,
along with the initial velocity and radiant position, necessary for
reliable determination of the heliocentric orbit of the observed
fireball. The orbits were computed by the method of Ceplecha
(1987).
To compute the photometric mass of the meteoroid, the ve-
locity dependence of the luminous efficiency was taken from
ReVelle & Ceplecha (2001). The mass dependence was ignored
by substituting 10 kg for the mass in their formula. Specifically,
the luminous efficiency for velocities above 25.4 km s−1was as-
sumed to be directly proportional to the velocity, reaching 6.5%
at 30 km s−1. A factor of 1500 W for zero magnitude meteor
Article number, page 5 of 24
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Fig. 6. Exposure coverage representing observing conditions in Central Europe during activity of Taurids in 2015. It is the fraction of real time
when all cameras in the network exposed to their total prescribed exposure time. The date corresponds to the evening date of the whole night.
Fig. 7. Activity of Taurids recorded by the DAFO cameras of the European Fireball Network in 2015. The number of presented Taurid fireballs in
the plot is 143 (total number is 144); S TAU from 28.11.2015 is out of range of the date axis. Date corresponds to the evening date of the whole
night.
(Ceplecha et al. 1998) was used to convert magnitudes into bolo-
metrically radiated energy.
The above-mentioned example clearly demonstrates high
precision and reliability of all parameters describing the atmo-
spheric trajectory, dynamics, photometry, and heliocentric orbit
not only for this particular case, but also for all Taurid fireballs
presented in Table 4 and Table 5. For this complex analysis of all
presented Taurid fireballs, i.e., the astrometric reduction of the
images, atmospheric trajectory computation, dynamic and pho-
tometric solutions, and finally orbital calculations, we used our
new software package BOLTRACK (J. Boroviˇ
cka).
Although the autumn weather, especially in November, is no-
toriously cloudy in Central Europe, the year 2015 was not so bad.
There were several clear nights, especially in the beginning of
November, and only a few nights were completely cloudy prac-
tically at all stations. This situation is illustrated in Figure 6 in
which the ratio of real to prescribed exposure time for all stations
in the network altogether and for each individual night cover-
ing the Taurids activity in 2015 is shown. Since the DAFOs also
work when the sky is only partly clear, some fireballs were cap-
tured even in the nights when it was mostly cloudy and could
be still used for this study. On the other hand, some fireballs
were recorded only from one station or their records were of a
quality that is insufficient to merit scientific analysis. Such cases
were excluded from our study. As a result of relatively favorable
weather conditions and the capability of our network, we were
able to cover the whole period of the enhanced Taurid activity
from the last decade of October to mid-November as shown in
Figure 7. It is difficult to construct the activity profile for such
a long interval from our data because it is difficult to take into
account all observational effects and correctly eliminate them.
So Figure 7 does not represent the real activity profile, but only
the uncorrected distribution of selected Taurid fireballs during
the whole interval of activity. As described in the following sec-
tions, we identified three different groups of Taurids in our data
set. These are the regular Southern and Northern Taurids (desig-
nated as S TAU and N TAU, respectively) and a new branch of
Southern Taurids, which we designate S TAU (SB). As shown
later, this new branch was responsible for the enhanced activity.
From Figure 7 we can see that enhanced Taurid activity caused
by this new branch of Southern Taurids fireballs started on Oc-
tober 24, culminated around November 5 and terminated on the
night of November 16/17. The S TAU (SB) was not observed
after this date even though on November 18 and 21-23 were at
least partly clear nights with good observing conditions. From
Figure 7 we also see that the enhanced activity increased gradu-
ally with several days of very high activity at the turn of October
and November. This interval was strongly affected by the full
Moon period, so fainter fireballs were below the sensitivity limit
of the digital all-sky cameras and radiometers especially in the
end of October. Therefore the number of fireballs on these nights
may be underestimated. On the other hand, the relatively steep
decrease of activity after November 5 seems to be real. With re-
gard to regular S and N Taurids, they are quite uniformly spread
over the entire interval of observed activity.
4. The 2015 Taurid data
The total number of Taurid fireballs recorded photographically
by our instruments at least from two stations in 2015 was about
Article number, page 6 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Fig. 8. Detailed view of the two brightest Taurids far over Poland recorded by the AFO (analog camera) at station Polom.
200. This is much more than we recorded in any previous year.
The main reason for this is evidently the unusually high Taurid
activity, but it is also caused by much more efficient observa-
tional system and also by a quite long period of relatively good
weather. For this study we selected 144 Taurids with complete
information about heliocentric orbits of individual meteoroids
and their physical properties as well. Our data set is unique not
because of the total number of used meteors but the high preci-
sion of the data for each individual case, which was obtained by
with high-resolution cameras and radiometers and elaborated re-
duction methods. Meteor records were reduced one-by-one and
all steps in the measurement and computation process were un-
der careful human supervision.
Before going to the statistical analysis of the whole data set,
we describe in more detail some remarkable fireballs.
4.1. Exceptional cases
4.1.1. EN311015_180520 and EN311015_231301 - two
brightest Taurids
It is a well-known fact that Taurids are quite rich in bright fire-
balls. However, 2015 was also in this aspect exceptional and our
cameras recorded several very bright Taurids during the whole
period of activity. Altogether 24 Taurids were brighter than −10
absolute magnitude and 10 were similarly bright or even brighter
than the full Moon. Moreover, two of those, both observed in the
first half of the night of October 31, are really remarkable not
only in this data set, but in all Taurids that we have recorded
within the EN until now. Both are shown in Figure 8, where a
small part of the all-sky image is shown. This image was taken
from station Polom by the AFO, i.e., on sheet film, where one
exposure was taken per night. Both bolides were observed in a
similar (northern) direction and flew over northern and central
Poland, respectively. The brighter bolide, which reached a peak
absolute magnitude of −18.6 (on the left), occurred at 18:05:20
UT and the second, with peak magnitude of −15.8,occurred 5
hours 7 minutes and 41 seconds later at 23:13:01 UT. This is the
reason why their directions of flight differ, although both bolides
had practically the same radiant. The first was so bright that
it belonged to the superbolide category. This spectacular Tau-
rid bolide was caused by a meteoroid with initial mass more
than 1000 kg, i.e., a meter-sized object. Because of its enormous
brightness, clear skies over large parts of Central Europe, and
convenient time of its occurrence (it was an unusually nice Sat-
urday evening), thousands of eyewitnesses were fascinated by
this extraordinary natural event. We obtained more reports of
one bolide than ever before. Apart from plenty of visual obser-
vations, all DAFOs and AFOs in our network (at 15 stations)
recorded it, which was crucial for reliable description of this su-
perbolide. In addition to our own photographic and radiomet-
ric records, we used also two casual images. The first one is
a high-resolution digital image from Studénka, Czech Repub-
lic, which was obtained from amateur astronomer B. Pelc. The
second digital image was taken by G. Zieleniecki at Czernice
Borowe, Poland, and was freely available on the internet. Alto-
gether we used 13 most suitable photographic and 5 radiometric
records. The situation with the second, much smaller, meteoroid
was similar. It was also recorded by all our cameras at all 15
stations, and we obtained also 4 high-resolution casual digital
images from northern region of the Czech Republic. These im-
ages, which we also partially used, were taken by T. Chlíbec at
Klínovec, L. Sklenár from Kunˇ
cice and Labem, D. Šˇ
cerba from
Dolní Údolí, and L. Shrbený from ˇ
Ríˇ
cany; this record also in-
cludes a spectrum of the bolide. In this case we used the best 12
photographic and 4 radiometric records for final analysis.
Since these fireballs were exceptional, we modeled them
with our semiempirical fragmentation model (Boroviˇ
cka et al.
2013). The model fits radiometric curves and deceleration. This
way we obtained more reliable initial masses of meteoroids
(1300 kg and 34 kg, respectively) and insight into their at-
mospheric fragmentation. Both meteoroids were effectively de-
stroyed high in the atmosphere under dynamic pressures <0.05
MPa. In both cases a small fragment (<1 kg) survived the ini-
tial destruction and fragmented further under pressures of ∼0.1
MPa. In comparison with other bright bolides (Boroviˇ
cka et al.
2017), both Taurids were extremely fragile.
Simultaneously with our network, both bolides were also
recorded by the cameras of the Polish Fireball Network. These
data were analyzed independently and were published by Olech
et al. (2016). Because our data differ from their data, we provide
here our complete results and compare them to those reported
in Olech et al. (2016). Atmospheric trajectories are given in Ta-
ble 1, light curves in Fig. 9, and heliocentric orbits in Table 2.
When computing the local azimuth and slope of the trajectory,
we took into account both the curvature of the Earth and the
curvature of the bolide trajectory due to gravity, which was sig-
nificant for EN311015_180520 (change of direction of flight by
0.17◦over the recorded length). Azimuths are measured from the
south clockwise. The apparent radiants given in Table 2 are valid
for the average points on the trajectories.
As shown later in this paper and that of Olech et al. (2016)
(in fact that paper is based only on these two bolides) data about
Article number, page 7 of 24
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Table 1. Atmospheric trajectory data for the EN311015_180520 (left) and EN311015_231301 (right) bolides.
Beginning Max. Terminal Beginning Max. Terminal
bright. bright.
Height (km) 114.724 ±0.025 80.8 57.644 ±0.030 120.026 ±0.030 74.4 57.305 ±0.016
Velocity (km s−1) 33.07 ±0.03 33.07 22 ±2 32.56 ±0.09 32.53 30 ±2
Longitude (◦E) 18.46416 ±0.00018 16.927 15.82901 ±0.00020 18.18064 ±0.00026 18.101 18.07087 ±0.00014
Latitude (◦N) 53.60723 ±0.00050 53.553 53.50244 ±0.00048 52.13173 ±0.00060 52.430 52.54390 ±0.00033
Slope (◦) 18.574 ±0.014 17.71 17.148 ±0.034 53.28 ±0.04 53.00 52.89 ±0.10
Azimuth (◦) 267.240 ±0.013 266.00 265.120 ±0.015 350.78 ±0.04 350.72 350.69 ±0.05
Time1(s) −1.07 2.22 4.68 −0.07 1.68 2.36
Total length (km) 186.3 78.5
1Time zero corresponds to 18:05:18 UT for EN311015_180520 and 23:13:00 UT for EN311015_231301.
Table 2. Apparent and geocentric radiants and orbital elements
(J2000.0) for the EN311015_180520 (left) and EN311015_231301
(right) meteoroids. Time is given for the average point of the recorded
trajectory.
EN311015_180520 EN311015_231301
Time (UT) 18h05m20.0s±0.1s23h13m01.5s±0.1s
αR(◦) 50.126 ±0.009 51.853 ±0.022
δR(◦) 16.452 ±0.016 15.66 ±0.04
v∞(km s−1) 33.068 ±0.030 32.56 ±0.09
αG(◦) 51.692 ±0.010 51.445 ±0.022
δG(◦) 14.592 ±0.017 14.49 ±0.04
vG(km s−1) 30.869 ±0.032 30.59 ±0.10
vH(km s−1) 37.32 ±0.02 37.34 ±0.06
a(AU) 2.250 ±0.009 2.258 ±0.027
e0.8724 ±0.0006 0.8689 ±0.0020
q(AU) 0.28715 ±0.00032 0.2960 ±0.0010
Q(AU) 4.212 ±0.018 4.22 ±0.05
ω(◦) 121.687 ±0.022 120.62 ±0.06
Ω(◦) 37.791 38.005
i(◦) 5.707 ±0.023 5.62 ±0.06
P(yr) 3.375 ±0.020 3.39 ±0.06
Perihelion 2012-07-26 ±7 d 2012-07-20 ±22 d
TPJup 2.952 ±0.009 2.953 ±0.028
these big bolides are of great importance. Since it may not be
simple to distinguish which data set is correct, we carry out an
analysis of the differences. The positions of the recorded be-
ginning and end points of the bolide depend on the sensitivity
of the instrument and the observing conditions. Nevertheless,
when plotting the trajectory of the first bolide on the map, the
solution of Olech et al. (2016) is shifted about 1.8 km to the
north. As for the observed apparent radiant, there is a difference
of 0.65◦in declination, i.e., 10 times their quoted uncertainty
(σ). For the second bolide, the larger difference is in right as-
cension (0.24◦, 4σ) and especially in entry velocity, which is
larger by 0.6 km s−1(6σ) in Olech et al. (2016). Although our
data were obtained from large distances, our results are based
on large number of records (in both cases more than 10) and the
solutions for both bolides are very consistent. The photograph
from Czernice Borowe, when combined with our cameras, pro-
vides convergence angles in excess of 60◦for the first bolide.
Czech cameras have mutual convergence angles up to 15◦. For
the second bolide the situation is even better, although the veloc-
ity was more difficult to measure. So there is no reason, why our
results should be different by more than the standard deviations
given in Table 1.
Fig. 9. Calibrated radiometric light curves of bolides
EN311015_180520 and EN311015_231301 (solid curves). For
EN311015_180520 data from two imaging cameras are also given
(crosses). After bolide maximum, most of radiometric signal was
produced by a stationary trail. Camera data contain only the bolide
moving further down. Time zero corresponds to 18:05:18 UT for
EN311015_180520 and 23:13:00 UT for EN311015_231301.
There is also at least a 3-5 seconds difference in the reported
time of appearance of the first fireball. Our radiometers are con-
tinuously corrected by PPS pulse of GPS and their timing preci-
sion is in millisecond range. A nice example how our radiome-
ters are synchronized is shown in Figure 4. Another discrepancy
is in the determination of the maximum absolute brightness for
both bolides. While Olech et al. (2016) determined the maxi-
mum absolute brightness −16.0±0.4 mag for the first bolide, we
found that it reached −18.6±0.2 mag. Our method described in
Section 3.1 relies on the linearity of radiometers even for strong
signals. Results from five independent radiometers were in per-
fect agreement. Similarly the brightness of the second bolide was
underestimated by Olech et al. (2016) by about 1 magnitude.
Regardless of these differences in the directly determined tra-
jectory parameters, we found another discrepancy in the calcu-
lation of orbital elements in Tables 3-5 of Olech et al. (2016).
We obtained significantly different results than those published
in Tables 5 and 6 of Olech et al. (2016) when we took their in-
put values of initial velocity, apparent radiant position (which
we recalculated from J2000.0 to the date that the bolides oc-
curred) time, and mean position for both bolides from their Ta-
bles 3 and 4 and used our program for orbital calculation; orbits
from this program were independently validated for example in
Article number, page 8 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Fig. 10. Detailed view on the very long Taurid fireball recorded by the DAFO (digital camera) at station Kunžak.
Clark & Wiegert (2011). We found the following differences for
the EN311015_180520 bolide (computed minus published): ∆a
=0.0077 AU, ∆e=0.0057, ∆ω=1.3◦(!), ∆i=0.07◦, and ∆P
=0.019 yr. For the EN311015_231301 bolide, differences are
∆a=0.1287 AU (!), ∆e=0.0087, ∆ω=0.1◦,∆i=0.035◦, and
∆P=0.20 yr. Some of these differences are really high, namely
1.3◦, in argument of perihelion for the first bolide and especially
0.128 AU in semimajor axis for the second bolide. With the ra-
diant and velocity given by Olech et al. (2016) this bolide would
be far from the 7:2 resonance with Jupiter, nevertheless, their
published orbit puts it in the resonance.
4.1.2. EN061115_164758: An almost horizontal Taurid
On November 6, 2015 during dawn, just after the Taurid radi-
ant rose above the horizon, a relatively faint Taurid fireball of
−5.1 maximum absolute magnitude traveled over a large part
of sky and was observed by several stations in the SW part
of our network. The sky was not completely dark, especially
from the stations in western part of the network, which were
closest to the fireball trajectory. However, thanks to the higher
sensitivity of the digital cameras, this extremely long fireball
was nicely recorded on three stations, Kunžak, Martinsberg and
Kuchaˇ
rovice, which enabled us to describe this exceptional Tau-
rid accurately. Owing to its small slope which was 7.7◦at the be-
ginning and during the flight decreased to only 5.6◦, the recorded
fireball trajectory was extremely long, i.e., exactly 258.7 km, and
its flight lasted 8.5 seconds. It is the longest Taurid fireball we
have ever recorded, both in duration and length. Thanks to a large
amount of data points, this Taurid has the best dynamic data and
the trajectory, i.e., also radiant, is also very precise. The initial
velocity of 31.285 km s−1was determined with a precision of
±7 m s−1. As for the brightest Taurid described in Sect. 4.1.1,
we took into account the curvature of the trajectory of the bolide
due to gravity, which was significant for such a long and low
inclined fireball (change of direction of flight by 0.18◦over the
recorded length). A detailed view of its luminous flight taken by
the DAFO at Kunžak station is shown in Figure 10. Additional
information about this fireball is given in Tables 4 and 5.
4.2. Radiants and orbits
In this section the radiants, velocities, and heliocentric orbits of
all 144 fireballs are evaluated. All elements in this paper are
given for equinox J2000.0. The data are presented in Table 4.
Figure 11 shows the dependency of geocentric radiant and ve-
locity on solar longitude (i.e., the longitude of the Sun at the
time of fireball observation). Thirteen fireballs were classified as
Northern Taurids. They can be easily recognized by their radi-
ant lying to the north of the ecliptic. All other fireballs belong
to Southern Taurids. Among them, a well-defined structure can
be recognized, where the radiant position and velocity are strict
linear functions of solar longitude. We call this structure a new
branch. Evidently, this branch was responsible for the enhanced
Taurid activity in 2015.
Regular Taurids also exhibit radiant motion but the spread of
individual radiants is much larger than for the new branch. For
the new branch, we found the following relationships:
αg=46.99◦+0.554 ·(λ−210◦) (1)
δg=14.00◦+0.060 ·(λ−210◦) (2)
vg=32.90 −0.293 ·(λ−210◦),(3)
where αgand δgare the right ascension and declination, respec-
tively, of the geocentric radiant (J2000.0), vgis the geocentric
velocity in km s−1, and λis solar longitude (J2000.0). Although
we defined the new branch on the basis of orbital elements rather
than radiants and velocities (see below), all fireballs of the new
branch had the radiant right ascension within 1.3◦and declina-
tion within 0.7◦from (1) & (2). The velocities were within 0.9
km s−1from relationship (3). We point out that this spread is real.
The precision of most of our data, as demonstrated in Sect. 3.1,
is <0.05◦in the radiant position and 0.1 km s−1in the velocity.
Fireballs from the branch were observed between solar lon-
gitudes 211◦– 234◦(October 25 – November 17). Taurids ob-
served before and after these dates belong to the background
population of Northern and Southern Taurid streams.
Longitude of perihelion, inclination, eccentricity, and peri-
helion distance as a function of solar longitude are plotted in
Fig. 12. Most notably, there is a concentration of orbits with lon-
gitude of perihelion, π(π= Ω + ω, where Ωis longitude of
ascending node and ωis argument of perihelion), at 158◦±2◦
(Fig. 12a). There is only a weak correlation with solar longitude.
Similarly, there is a concentration of orbits with inclinations of
5.5◦±1◦(Fig. 12b). Regular Taurids show much larger spread,
145 – 175◦in πand 2 – 7◦in inclination.
Eccentricities and perihelion distances of the members of the
new branch are steep functions of solar longitude (Figs. 12c,d),
Article number, page 9 of 24
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Fig. 11. Position of geocentric radiant and geocentric velocity as a
function of solar longitude for Taurids observed in 2015. Northern and
Southern Taurids are shown by different symbols and the Southern Tau-
rids belonging to the new branch are highlighted in light blue. The error
of the data is smaller than the size of the symbols in most cases.
i.e.,
e=0.901 −0.00403 ·(λ−210◦) (4)
q=0.224 +0.0092 ·(λ−210◦).(5)
All eccentricities lie within 0.012 from (4) and perihelia lie
within 0.027 AU from (5). Again, regular Taurids show much
larger scatter.
The new branch is best recognized in the plot of longitude of
perihelion, π, versus latitude of perihelion, β(sin β=sin ωsin i,
where iis inclination), presented in Fig. 13. We can state that
the new branch has πbetween 155.9 – 160◦and βbetween 4.2
– 5.7◦. For regular Southern Taurids the observed spread in βis
2.5 – 6.5◦. Northern Taurids have negative β.
Semimajor axes are plotted in Fig. 14. For regular Taurids,
they lie between 1.9 and 2.4 AU. According to the model of
Asher & Clube (1993), the enhanced activity is caused by mete-
oroids trapped in the 7:2 resonance with Jupiter. The resonance is
located at 2.256 AU and extends from about 2.231 AU to 2.281
AU (Asher & Clube 1993). With two exceptions, the semima-
jor axes of all meteoroids with longitudes and latitudes of per-
ihelia within the above-defined limits fall in the 7:2 resonance.
Only two meteoroids had significantly lower semimajor axes,
2.15 – 2.16 AU. We consider them to be interlopers from the
background population of Southern Taurids, although the 15:4
resonance located at 2.155 AU might be at work here.
On the contrary, some Southern Taurids with perihelia out-
side the new branch limits were also in the 7:2 resonance. As
seen in Fig. 13, all of the Souther Taurids had an orientation of
perihelia relatively close to the new branch. Nevertheless, some
Northern Taurids were in the 7:2 resonance as well and they were
far from the new branch.
There is no correlation between semimajor axis and solar
longitude. The Tisserand parameter with respect to Jupiter in-
creases with solar longitude from 2.9 to 3.1 within the new
branch. This is due to the decreasing eccentricity. The often cited
boundary at TJup =3 or 3.05 (e.g., Tancredi 2014) has no signif-
icance in this case.
According to the above definitions based on perihelion ori-
entation and semimajor axis, there are 13 Northern Taurids in
our data set, 18 regular Southern Taurids, and 113 members of
the new branch.
It is evident that the new branch represents an orbital struc-
ture that is much more compact than regular Taurids. Since the
activity of the new branch lasted almost one month, it cannot,
however, be a narrow filament. In order to visualize the new
branch, we plotted selected orbits covering the whole activity pe-
riod in Fig. 15. Unlike usual meteoroid streams, where the orbits
near perihelion largely overlap, here we see a concentric ring of
orbits near perihelion, which is more than 0.2 AU wide. As the
Earth moves around the Sun, it encounters first the orbits with
smaller perihelia and larger eccentricities. With increasing solar
longitude, orbits with progressively larger perihelia and smaller
eccentricities are encountered. Since all of the semimajor axes
are similar, eccentric orbits have larger aphelia than less eccen-
tric orbits and the orbits therefore intersect at about 3.6 AU.
4.3. Physical properties
The Taurids in our sample reached maximum absolute magni-
tude between −2 and −18.6. The photometric masses range from
0.1 gram to 1300 kg, i.e., there is a range of 7 orders of magni-
tude in mass. The mass distribution is given in Fig. 16, which
shows that the new branch has a higher proportion of massive
meteoroids. The data in Fig. 16 are biased because brighter me-
teors could be observed over large distances and under worse
conditions than faint meteors, nevertheless, the bias is the same
for all branches.
Article number, page 10 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Fig. 12. Selected orbital elements as a function of solar longitude for Taurids observed in 2015. The symbols are the same as in Fig. 11. Errors are
in most cases smaller than symbol sizes and for clarity are plotted only for regular Taurids.
The beginning, maximum brightness, and end heights of all
studied fireballs are plotted as a function of photometric mass in
Fig. 17. These heights are good proxies to meteoroid structure,
although they depend to some extent on observational circum-
stances (e.g., range to the fireball) and on the slope of the tra-
jectory. Beginning heights show no dependence on mass and are
generally between 90 and 110 km. For consistency we use only
data from digital all-sky cameras in the plot. The two bright-
est fireballs were captured by the narrow-field cameras at higher
altitudes (see Table 1). On the other hand, both these fireballs
were located far from the all-sky cameras; the beginning of
EN 311015_180520 was 390 km from the closest camera and
the beginning of EN 311015_231301 was 270 km distant. If ob-
served from closer distances, the beginnings would lie somewhat
higher.
The maximum and end heights show large scatter. Many
fireballs exhibited multiple flares of similar brightness. Nev-
ertheless, there were differences in physical properties of the
meteoroids. This fact is mostly evident from the end heights.
There are differences of 25 km or more for meteoroids of sim-
ilar masses. The expected trend of deeper penetration for larger
bodies is only weakly present. The lowest end heights (below
50 km) were achieved by two quite small meteoroids. There are
no obvious differences in physical properties between different
branches of the stream.
Since the end height depends not only on the meteoroid prop-
erties but also on trajectory slope and entry speed, the PE crite-
rion (Ceplecha & McCrosky 1976), which compensates for these
effects, can be used to better evaluate meteoroid strengths. Ac-
cording to the PE criterion, meteoroids are classified into four
types: I, II, IIIA, and IIIB (Ceplecha 1988). Type I corresponds
to stony meteorites and type IIIB to soft cometary material. Fig-
ure 18 shows Taurid PE classification as a function of mass.
We can see that Taurids cover all four types, with a clear trend
of larger meteoroids being more fragile. Most of meteoroids
smaller than 30 grams belong to type II. Some meteoroids with
masses on the order of one gram clearly belong to type I. On
the other hand, most meteoroids above 30 gram belong to type
Article number, page 11 of 24
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Fig. 13. Orientation of perihelia (latitude versus longitude) for Southern
Taurids observed in 2015. This plot was used to define the limits of the
new branch, as indicated by the ellipse. The fireballs that fell within
these limits but had different semimajor axes (outside the 7:2 resonance)
are plotted in purple. The fireballs outside these limits but within the
resonance are plotted in dark blue.
Fig. 14. Semimajor axis as a function of solar longitude for Taurids
observed in 2015. For symbol explanation see Figs. 11 and 13. Error
bars are plotted for all fireballs. The extent of the 7:2 resonance with
Jupiter according to Asher & Clube (1993) is indicated.
IIIA or IIIB and only type IIIB is present above 300 gram. The
fact that the two largest meteoroids were very fragile was con-
firmed by fragmentation modeling (Sect. 4.1.1). Significant dif-
ferences between small and large meteoroids suggest the exis-
tence of some hierarchical structure and will be subject of future
studies.
Similar heterogeneity of Taurid physical properties was ob-
served recently by Matloviˇ
c et al. (2017). Brown et al. (2013)
reported a Taurid that penetrated down to 35 km and Madiedo
Fig. 15. Selected orbits of the Taurids from the new branch projected to
the plane of ecliptic.
Fig. 16. Number of fireballs as a function of photometric mass for
Northern Taurids, regular Southern Taurids, and the new branch.
et al. (2014) and another one reaching 42.5 km. These authors
suggested that Taurids might drop meteorites. Our data do not
seem to support this possibility, since at least a ∼1 kg type I
Taurid meteoroid would be needed to produce any meteorites.
The SPMN 051010 fireball observed by Madiedo et al. (2014)
on October 5, 2010 had a semimajor axis 3.0 AU and perihelion
0.47 AU. It may not be Taurid at all. The SOMN 101031 fireball
observed by Brown et al. (2013), with a semimajor axis 2.9 AU,
was also not a typical Taurid.
All atmospheric and physical data are given in Table 5.
Article number, page 12 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Table 3. Orbital elements of asteroids discussed here as taken from the JPL database and converted to J2000.0 equinox.
Asteroid λa e q i ωΩπ β
2005 UR 216.44 2.254 0.882 0.266 6.94 140.40 20.03 160.43 4.42
2015 TX24 218.81 2.269 0.872 0.290 6.05 126.80 32.99 159.79 4.84
2005 TF50 219.60 2.272 0.869 0.298 10.70 159.67 0.66 160.33 3.70
2004 TG10 223.32 2.234 0.862 0.308 4.18 317.11 205.13 162.23 −2.84
Fig. 17. Fireball heights at beginning, end, and maximum light as a
function of photometric mass. Northern Taurids are plotted as dia-
monds, regular Southern Taurids as circles, and new branch members
as squares.
5. Related asteroids
We performed a search for asteroids with orbits similar to the
new Taurid branch responsible for the enhanced activity in 2015.
For that purpose, asteroids with q<0.6 AU, 1.8 AU <a<
2.8 AU, and i<12◦were selected from the JPL Small-Body
Database2. There are 329 such asteroids known. We then plotted
selected orbital elements as a function of solar longitude at Earth
Minimum Orbit Intersection Distance (MOID) to be compared
with the observed fireballs. For fireballs we used solar longitude
at the time of impact as the independent variable. Since the aster-
oids did not impact Earth and their orbits do not intersect Earth’s
orbit, we used for comparison the solar longitude, as seen from
the asteroid at the time when the asteroid is closest to the Earth’s
orbit.
Figure 19 shows the comparison plot for eccentricity. We see
that there is nearly random distribution of asteroids with eccen-
tricities smaller than 0.84 in the solar longitudes of interest. At
higher eccentricities (0.86 – 0.88), however, there is a notice-
able concentration of four asteroids (2005 UR, 2015 TX24, 2005
TF50, and 2004 TG10) near solar longitude of 220◦. This con-
centration overlaps with the new Taurid branch. Moreover, it fol-
lows the same trend of decreasing eccentricity with increasing
solar longitude.
Other orbital elements are compared in Fig. 20. Perihelion
distance is basically a mirror image of eccentricity. Semimajor
axes of all four asteroids of interest fall within the Taurid branch
2http://ssd.jpl.nasa.gov/sbdb_query.cgi, accessed January 25, 2017
Fig. 18. Value of PE criterion (Ceplecha & McCrosky 1976) as a func-
tion of photometric mass for all observed Taurids. Northern Taurids are
plotted as diamonds, regular Souther Taurids as circles, and new branch
members as squares. The dashed horizontal lines define the types I, II,
IIIA, and IIIB.
Fig. 19. Orbital eccentricity as a function for solar longitude at the clos-
est approach to the Earth’s orbit for 2015 Taurid fireballs and asteroids
from JPL database. Asteroids, which are likely related to the new Tau-
rid branch are highlighted in magenta. Asteroids for which the relation
to the new branch was considered but not confirmed are shown as filled
rectangles. They may be related to other parts of the Taurid complex.
Article number, page 13 of 24
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Fig. 20. Semimajor axis, inclination, perihelion distance, and longitude of perihelion as a function for solar longitude at the closest approach
to the Earth’s orbit for 2015 Taurid fireballs and asteroids from JPL database. Asteroids, which are likely related to the new Taurid branch are
highlighted. The symbols are the same as in Fig. 19. The inclinations of Northern Taurids and asteroids with Ω>180◦, which encounter the Earth
near their descending node in October/November, are plotted as negative.
range, i.e., also within the 7:2 resonance. As for inclination, only
2015 TX24 falls exactly within the Taurid branch range. The
2005 UR asteroid is somewhat offbut only about a half degree
from the edge of the Taurid branch. However, Taurid fireballs
represent the part of the stream, which intersects Earth’s orbit.
The whole stream is probably somewhat wider, so we consider
it likely that 2005 UR is also part of the stream. The 2005 TF50
asteroid matches all other elements very well but has an incli-
nation of 10.7◦, i.e., more than 4 degrees from the edge of the
Taurid branch. On the other hand, the orientation of perihelion is
not so far from the new Taurid branch (Fig. 22). But the orbit of
2004 TG10 is oriented in the opposite way relative to the eclip-
tic. This asteroid may be in fact related to Northern Taurids. At
least two asteroids, 2015 TX24 and 2005 UR, are therefore good
candidates for direct membership in the new branch of Southern
Taurids.
Asteroid 2015 TX24 was discovered by Pan-STARRS 1 on
October 8, 2015 and was observed for 18 days in October 2015.
It passed closest to the Earth’s orbit on October 28, 2015, i.e.,
during the enhanced Taurid activity. The MOID of the Earth is
0.010 AU. The asteroid has an absolute magnitude of H=21.5,
which corresponds to diameter 200 – 300 meters, assuming
albedo in the range 0.10 – 0.05.
Asteroid 2005 UR was discovered by the Catalina Sky Sur-
vey on October 23, 2005 and was observed for six days in Oc-
tober 2005. The MOID of the Earth is 0.034 AU. The absolute
magnitude is H=21.6, i.e., very similar to that of 2015 TX24.
Asteroid 2005 UR approached the Earth’s orbit at the end of De-
cember 2015 and was therefore only 17◦in mean anomaly be-
hind the Taurids observed in 2015. Moreover, as noted by Olech
et al. (2016), Taurid activity was also enhanced when the asteroid
passed close to the Earth in October 2005.
Article number, page 14 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Fig. 21. Orbits of 2005 UR and 2015 TX24 in comparison with all Tau-
rids orbits from the new branch (gray).
Fig. 22. Comparison of perihelia orientation of 2015 Taurids with aster-
oids and comets from the JPL database.
The orbits of both 2005 UR and 2015 TX24 are plotted in
Fig. 21 together with the fireball orbits. There is a good overlap.
Orbital elements of all four asteroids discussed here are given in
Table 3. Asteroid 2004 TG10 is a large object with H=19.4.
The albedo is very low and the diameter was estimated to be
1.40 ±0.51 km (Nugent et al. 2015). The possible relation of
this asteroid to the Taurids was suggested already by Jenniskens
(2006), Porubˇ
can et al. (2006), and Babadzhanov et al. (2008).
Asteroid 2005 TF50, with H=20.3, is of intermediate size.
Its relation to comet 2P/Encke and the Taurids was proposed by
Porubˇ
can et al. (2006) and Olech et al. (2016).
6. Discussion
We presented probably the most precise Taurid orbits obtained
to date. Thanks to the sufficient precision of semimajor axes, the
theory of Asher & Clube (1993) and Asher & Izumi (1998) that
the meteoroids responsible for enhanced Taurid activity are in
7:2 resonance with Jupiter could be confirmed (at least for 2015
meteors). This fact cannot be revealed from lower precision data
such as those of Matloviˇ
c et al. (2017)3. Moreover, we found
that the Taurid branch, which is responsible for the enhanced ac-
tivity in 2015, forms an interesting orbital structure. Although
the enhanced activity lasted for 23 days according to our data,
all orbits had very similar orientation of the line of apsides, i.e.,
the longitude and latitude of perihelion. Since semimajor axes
were in a narrow range and all observed meteoroids had to in-
tersect Earth’s orbit, only one free parameter remains. That is
why there is a good correlation between the longitude of the
ascending node (or, equivalently, solar longitude at the date of
observation), eccentricity, and perihelion distance.
There was, nevertheless, some spread of orbital elements
within the new branch. The longitudes of perihelia were within
the range 155.9 – 160◦and latitudes of perihelia within the range
4.2 – 5.7◦. The semimajor axes were within the resonance lim-
its, 2.23 – 2.28 AU. The additional condition for the new branch
membership follows from the limited period of activity and can
be expressed, for example, in terms of eccentricity lying between
0.80 – 0.90. Three asteroids, 2015 TX24, 2005 UR, and 2005
TF50, fully or nearly satisfy all these conditions. Fig. 22 shows
three other asteroids (2003 WP21, 2007 UL12, and 2015 LM21)
with perihelia orientation not far from the new branch, but none
of them simultaneously fulfills both the semimajor axis and ec-
centricity criteria.
Since the Earth does not encounter the new branch every
year, it is evident that meteoroids of the new branch are not
spread along the whole orbit. The model and observations of
Asher & Clube (1993) and Asher & Izumi (1998) suggest that
the enhanced activity of Taurids is caused by a resonant swarm
of meteoroids, which extends ±30 – 40◦from the center of the
swarm in mean anomaly. It does not, however, necessarily mean
that the new branch observed in 2015 is identical to or represen-
tative of the whole swarm. The orbits of meteoroids observed by
the EN during the enhanced activity in 1995 had somewhat dif-
ferent characteristics than in 2015; these had larger semimajor
axes and smaller perihelia, which did not change so much with
solar longitude.
The new branch contains quite large bodies. Our brightest
fireball was caused by a body in excess of 1000 kg, which cor-
responds to diameter more than one meter, assuming that bulk
density was not higher than 2000 kg m−3. This body was disinte-
grated very high in the atmosphere and likely had high porosity
and low bulk density. The NASA JPL fireball page4lists a fire-
ball with 10 times higher radiated energy, which occurred on
the same day (October 31, 2015 11:34:30 UT) above the Pa-
cific Ocean at a quite large height of 71 km. Considering the
unusual height, it is likely that that fireball belonged to the Tau-
rid new branch as well. The size of that body was 2-3 meters or
more. Two similar, slightly smaller, events occurred on Novem-
ber 2, 2005 (05:16:47 and 07:04:32), also over Pacific Ocean.
The heights of these bolides were 74 and 68.5 km, respectively.
These three fireballs are among the top five events with largest
heights among the 288 fireballs with known heights listed at the
NASA JPL page. Their trajectories and velocities are not given
but the Taurid radiant was above the horizon in all cases. We note
that 2005 was also a year of enhanced Taurid activity.
3We observed 10 fireballs from their sample and their semimajor axes
are often offwith respect to ours by several tenths of AU.
4http://neo.jpl.nasa.gov/fireballs/, accessed February 3, 2017
Article number, page 15 of 24
A&A proofs: manuscript no. Spurny_Taurids
Fireball data therefore prove the presence of meter-sized
bodies among the Taurid new branch. Based on orbital similarity,
we argue that asteroids of several hundred meters in diameter are
members of the Taurid new branch as well. This is almost certain
for 2015 TX24, very likely for 2005 UR, and possible for 2005
TF50. We are not speaking about a distant relationship. The dis-
covered Taurid branch is simply a population of bodies with the
size range from several millimeters to several hundred of me-
ters, which all move together around the Sun. Every few years,
the Earth is encountering this branch for a period of about three
weeks. During that time, the chance of impact of an asteroid of
significant size (tens of meters) is significantly enhanced. Even
if intrinsically weak, bodies of such size can penetrate deep in
the atmosphere (Shuvalov & Artemieva 2002) and pose a hazard
to the ground.
We will allow theoretical celestial mechanicians to explain
the formation and evolution of the Taurid new branch and the
Taurid complex as a whole. A structure similar to the new branch
could be created by a disruption of a parent body at heliocentric
distance of about 3.6 AU (where the orbits come close together)
but ejection velocities up to 1.5 km s−1and subsequent removal
of all non-resonant orbits would be needed. Also, asteroids 2005
TF50, 2015 TX24, and 2005 UR can all be related to 2004 TG10
but located at a different phase along the secular cycle as com-
puted for 2004 TG10 by Porubˇ
can et al. (2006). Asteroid 2005
TF50 is about 2000 years behind, 2005 UR is about 2300 years
behind, and 2015 TX24 is about 2400 years behind 2004 TG10.
The elements ω,Ω, and iall agree well with this assumption. For
2005 TF50 and 2015 TX24 eand qare also in agreement. The
new Taurid branch can be also part of this relation. In fact, the or-
bital elements of the theoretical Southern Taurid meteors derived
from 2004 TG10, as computed by Babadzhanov et al. (2008), fall
perfectly among the Taurid branch fireballs in Fig. 12. Only in π
there is a difference of 2.5◦. But only the central part of the new
branch at λ∼220◦can be explained in this way.
7. Conclusions
We presented data of unprecedented precision for a large sample
of 144 Taurid fireballs observed by the European fireball net-
work in 2015. This data set contains precise and detailed data
on the Taurids covering 7 orders in mass, i.e., from tenths of a
gram to one-ton meteoroids. We have shown that the enhanced
Taurid activity in 2015 was produced by a well-defined branch
embedded within the much broader Southern Taurid stream. The
new branch can be characterized by the longitudes of perihelia
lying between 155.9 – 160◦, latitudes of perihelia between 4.2
– 5.7◦, semimajor axes between 2.23 – 2.28 AU, and eccentrici-
ties between 0.80 – 0.90. These orbits form a concentric ring in
the inner solar system with perihelia between 0.23 – 0.45 AU.
The new branch lies within the semimajor axis range spanned
by the 7:2 resonance, indicating strongly that the meteoroids re-
sponsible for the outbursts are within this resonance, as expected
from the model of Asher & Clube (1993). The Earth was the en-
countering members of the new branch at their ascending nodes
between October 25 and November 17. The orbital configuration
of the branch cause meteoroids with progressively lower eccen-
tricities, larger perihelion distances, and lower entry velocities to
encounter the Earth during the activity period.
The explanation of the structure and evolution of the new
branch and its relation to the whole Taurid complex must be left
to future theoretical studies. Nevertheless, we confirm earlier ob-
servations that the Taurid stream contains large meteoroids. This
is valid for the new branch in particular. The largest object we
observed was at least one meter in diameter. A ten times more
massive object observed on the same day over the Pacific Ocean
probably belonged to this new branch as well. Moreover, the or-
bits of asteroids 2015 TX24 and 2005 UR, both of diameters of
several hundreds of meters, place them within the new Taurid
branch as well. It is therefore very likely that the branch also
contains numerous objects of decameter size. Although our data
show that large Taurids have porous and fragile structure, objects
of tens or hundreds of meters in size pose a hazard to the ground
even if they have low intrinsic strength. Theoretical and obser-
vational studies and searches for related asteroids belonging to
this newly discovered and described branch of Southern Tau-
rids are therefore highly recommended. A better understanding
of this real source of potentially hazardous objects that are large
enough to cause significant regional or even continental damage
on the Earth is a task of capital importance.
Acknowledgements. This work was supported by the Praemium Academiae of
the Czech Academy of Sciences, grant 16-00761S from the Czech Science Foun-
dation, and the Czech institutional project RVO:67985815. Operation of the Slo-
vak station Stará Lesná was supported by the project ITMS No. 26220120029,
based on the supporting operational Research and development program financed
from the European Regional Development Fund. We thank especially J. Ke-
clíková, but also L. Shrbený and H. Zichová for a careful measuring of all pho-
tographic images. We also thank B. Pelc, T. Chlíbec, L. Sklenár and D. Š ˇ
cerba
for their images of two brightest Taurids.
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Article number, page 16 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Table 4. Radiant and orbital data for 2015 Taurid fireballs. The code of each fireball also contains the date (in ddmmyy format) and GMT time
corresponding to beginning rounded to whole second (in hhmmss format)
Code Branch1λαgδgvga e q ωiπ
EN231015_204348 S 209.908 49.00 15.31 35.04 2.387 0.9249 0.1792 134.92 5.39 164.84
0.01 0.02 0.03 0.012 0.0005 0.0003 0.03 0.04 0.03
EN231015_211327 N 209.928 42.26 20.04 30.16 1.999 0.8578 0.2842 303.17 5.02 153.09
0.02 0.02 0.06 0.013 0.0012 0.0006 0.03 0.04 0.03
EN241015_004546 N 210.075 45.88 18.83 32.44 2.074 0.8913 0.2255 309.90 2.46 159.94
0.12 0.08 0.03 0.020 0.0006 0.0014 0.24 0.14 0.24
EN241015_185031 S 210.825 42.91 11.61 28.19 1.975 0.8272 0.3414 116.78 5.51 147.62
0.01 0.01 0.01 0.003 0.0003 0.0002 0.02 0.01 0.02
EN251015_022301 SB 211.138 47.62 13.76 32.63 2.269 0.8955 0.2370 127.73 6.26 158.88
0.01 0.04 0.05 0.013 0.0008 0.0005 0.04 0.06 0.04
EN251015_031725 SB 211.176 46.32 13.59 31.73 2.265 0.8847 0.2612 124.80 5.54 155.99
0.03 0.02 0.05 0.013 0.0008 0.0006 0.06 0.03 0.06
EN261015_213736 SB 212.933 48.99 14.44 32.37 2.253 0.8921 0.2430 127.03 5.66 159.97
0.03 0.03 0.10 0.028 0.0017 0.0010 0.07 0.05 0.07
EN261015_224031 SB 212.977 48.51 13.96 31.98 2.263 0.8874 0.2549 125.55 5.99 158.54
0.03 0.03 0.08 0.022 0.0014 0.0008 0.06 0.05 0.06
EN271015_220749 SB 213.951 49.26 13.94 31.74 2.246 0.8838 0.2610 124.85 6.19 158.82
0.01 0.05 0.03 0.008 0.0005 0.0004 0.04 0.07 0.04
EN281015_011855 S 214.084 43.91 11.12 26.78 2.005 0.8057 0.3896 111.24 5.73 145.34
0.03 0.07 0.07 0.014 0.0018 0.0010 0.08 0.07 0.08
EN301015_222401 SB 216.958 51.08 14.52 30.96 2.235 0.8733 0.2832 122.22 5.65 159.19
0.02 0.06 0.05 0.013 0.0009 0.0006 0.05 0.08 0.05
EN311015_002325 N 217.040 44.77 19.16 28.36 2.349 0.8436 0.3674 292.16 2.41 149.17
0.01 0.01 0.04 0.012 0.0010 0.0005 0.02 0.01 0.02
EN311015_023900 SB 217.134 51.15 14.34 30.90 2.246 0.8726 0.2861 121.83 5.89 158.98
0.01 0.03 0.04 0.011 0.0008 0.0005 0.04 0.04 0.04
EN311015_025717 SB 217.147 51.20 14.38 30.94 2.249 0.8732 0.2850 121.95 5.86 159.11
0.52 0.04 0.03 0.089 0.0024 0.0061 1.03 0.24 1.03
EN311015_172431 SB 217.749 51.56 14.50 30.82 2.259 0.8719 0.2893 121.40 5.76 159.17
0.02 0.03 0.04 0.012 0.0008 0.0004 0.04 0.05 0.04
EN311015_180520 SB 217.777 51.69 14.59 30.87 2.250 0.8724 0.2872 121.69 5.71 159.48
0.01 0.02 0.03 0.009 0.0006 0.0003 0.02 0.02 0.02
EN311015_182902 SB 217.794 50.83 14.50 30.37 2.267 0.8665 0.3026 119.81 5.31 157.62
0.02 0.03 0.07 0.021 0.0015 0.0007 0.03 0.03 0.03
EN311015_185530 SB 217.812 51.17 14.68 30.59 2.265 0.8693 0.2960 120.59 5.28 158.42
0.01 0.03 0.05 0.015 0.0011 0.0005 0.03 0.04 0.03
EN311015_192126 S 217.830 49.84 13.99 29.62 2.260 0.8563 0.3247 117.29 5.34 155.13
0.01 0.01 0.03 0.007 0.0006 0.0003 0.02 0.02 0.02
EN311015_200534 SB 217.861 51.36 14.57 30.59 2.249 0.8689 0.2949 120.78 5.51 158.65
0.02 0.07 0.06 0.017 0.0012 0.0007 0.06 0.09 0.06
EN311015_202117 SB 217.872 50.82 14.66 30.23 2.238 0.8640 0.3044 119.71 5.06 157.60
0.01 0.01 0.00 0.002 0.0001 0.0001 0.02 0.01 0.02
EN311015_211904 SB 217.912 51.80 14.74 30.96 2.275 0.8743 0.2860 121.73 5.56 159.65
0.06 0.02 0.06 0.019 0.0011 0.0009 0.13 0.04 0.13
EN311015_230919 SB 217.988 51.80 14.69 30.79 2.245 0.8713 0.2889 121.49 5.58 159.50
0.03 0.02 0.06 0.015 0.0011 0.0006 0.06 0.03 0.06
EN311015_231301 SB 217.991 51.44 14.49 30.59 2.258 0.8689 0.2960 120.62 5.62 158.62
0.02 0.04 0.10 0.027 0.0020 0.0010 0.06 0.06 0.06
EN011115_013625 SB 218.091 51.42 14.58 30.60 2.279 0.8696 0.2971 120.41 5.49 158.51
0.01 0.03 0.05 0.013 0.0009 0.0005 0.03 0.03 0.03
EN011115_033911 N 218.176 50.88 20.51 31.26 2.291 0.8793 0.2765 302.85 2.69 160.99
0.28 0.06 0.11 0.056 0.0022 0.0035 0.56 0.11 0.56
EN011115_174410 SB 218.763 51.87 14.84 30.40 2.256 0.8665 0.3013 120.00 5.22 158.77
0.01 0.02 0.01 0.004 0.0003 0.0002 0.02 0.02 0.02
EN011115_183646 S 218.799 51.61 15.34 30.31 2.259 0.8657 0.3034 119.74 4.46 158.55
0.06 0.06 0.19 0.055 0.0040 0.0019 0.13 0.08 0.13
EN011115_191104 SB 218.823 51.60 14.15 29.98 2.231 0.8599 0.3127 118.77 5.86 157.61
0.01 0.01 0.03 0.007 0.0005 0.0003 0.02 0.01 0.02
EN011115_200918 SB 218.864 51.96 14.48 30.28 2.244 0.8643 0.3044 119.68 5.68 158.56
0.03 0.06 0.04 0.013 0.0009 0.0006 0.07 0.08 0.07
EN011115_223909 SB 218.968 52.28 14.64 30.47 2.253 0.8671 0.2994 120.23 5.64 159.21
0.01 0.02 0.04 0.011 0.0008 0.0004 0.03 0.03 0.03
Article number, page 17 of 24
A&A proofs: manuscript no. Spurny_Taurids
Table 4. continued.
Code Branch1λαgδgvga e q ωiπ
EN011115_234207 SB 219.011 52.47 14.88 30.64 2.263 0.8697 0.2948 120.72 5.46 159.75
0.03 0.03 0.16 0.043 0.0032 0.0016 0.07 0.05 0.07
EN021115_020950 SB 219.114 51.90 14.79 30.26 2.278 0.8652 0.3071 119.23 5.22 158.36
0.02 0.02 0.04 0.012 0.0009 0.0005 0.04 0.02 0.04
EN021115_021740 SB 219.119 51.96 14.57 30.19 2.262 0.8638 0.3081 119.18 5.51 158.31
0.02 0.05 0.05 0.014 0.0011 0.0007 0.05 0.06 0.05
EN021115_022525 SB 219.125 52.64 14.55 30.60 2.259 0.8688 0.2964 120.56 5.93 159.70
0.03 0.04 0.05 0.013 0.0009 0.0006 0.06 0.05 0.06
EN021115_024553 N 219.139 47.24 20.59 27.81 2.121 0.8269 0.3671 293.11 3.20 152.22
0.05 0.02 0.04 0.010 0.0009 0.0007 0.10 0.02 0.10
EN021115_182450 SB 219.792 51.84 14.14 29.61 2.262 0.8558 0.3262 117.09 5.76 156.90
0.39 0.19 0.04 0.064 0.0022 0.0046 0.77 0.28 0.77
EN021115_195540 SB 219.855 52.70 14.82 30.26 2.274 0.8649 0.3072 119.23 5.44 159.10
0.02 0.03 0.02 0.005 0.0003 0.0003 0.04 0.04 0.04
EN021115_201534 SB 219.868 52.22 14.95 29.97 2.272 0.8612 0.3153 118.31 5.01 158.19
0.03 0.03 0.09 0.027 0.0020 0.0010 0.06 0.04 0.06
EN021115_205431 N 219.895 52.44 20.31 30.88 2.248 0.8734 0.2845 302.04 1.84 161.90
0.02 0.02 0.05 0.013 0.0009 0.0005 0.03 0.03 0.03
EN021115_213614 SB 219.925 52.39 14.96 30.03 2.270 0.8620 0.3134 118.53 5.07 158.47
0.02 0.05 0.07 0.021 0.0015 0.0008 0.05 0.06 0.05
EN021115_215818 SB 219.940 52.49 14.71 30.05 2.272 0.8620 0.3134 118.52 5.43 158.48
0.02 0.07 0.05 0.014 0.0010 0.0006 0.06 0.09 0.06
EN021115_220435 SB 219.944 52.45 14.70 29.99 2.265 0.8611 0.3146 118.41 5.41 158.37
0.01 0.02 0.05 0.013 0.0010 0.0005 0.03 0.02 0.03
EN021115_232112 SB 219.998 52.14 14.55 29.78 2.277 0.8587 0.3217 117.55 5.41 157.56
0.01 0.02 0.04 0.012 0.0009 0.0005 0.03 0.03 0.03
EN021115_234348 S 220.013 50.43 14.32 28.59 2.247 0.8419 0.3552 113.84 4.73 153.87
0.04 0.06 0.11 0.029 0.0026 0.0013 0.09 0.07 0.09
EN021115_235259 SB 220.020 52.65 14.71 30.02 2.250 0.8610 0.3128 118.67 5.48 158.70
0.01 0.01 0.03 0.008 0.0006 0.0003 0.02 0.01 0.02
EN031115_002007 SB 220.038 52.51 14.65 29.83 2.232 0.8580 0.3169 118.27 5.44 158.33
0.02 0.03 0.03 0.009 0.0007 0.0004 0.04 0.04 0.04
EN031115_011247 SB 220.075 53.06 14.70 30.22 2.249 0.8636 0.3068 119.37 5.70 159.46
0.02 0.02 0.06 0.017 0.0013 0.0007 0.04 0.03 0.04
EN031115_012404 SB 220.083 52.76 13.98 30.02 2.278 0.8613 0.3159 118.21 6.41 158.31
0.02 0.05 0.09 0.023 0.0018 0.0010 0.06 0.07 0.06
EN031115_025102 SB 220.143 52.88 14.59 30.06 2.253 0.8616 0.3119 118.76 5.72 158.92
0.02 0.12 0.04 0.013 0.0009 0.0008 0.10 0.15 0.10
EN031115_031920 SB 220.163 52.25 14.27 29.67 2.269 0.8568 0.3250 117.19 5.74 157.37
0.02 0.02 0.12 0.030 0.0025 0.0014 0.06 0.03 0.06
EN031115_193751 SB 220.844 52.95 14.53 29.73 2.276 0.8577 0.3239 117.29 5.65 158.14
0.07 0.03 0.03 0.014 0.0007 0.0008 0.14 0.04 0.14
EN031115_195654 SB 220.857 53.26 14.89 29.91 2.261 0.8599 0.3168 118.16 5.37 159.03
0.04 0.08 0.10 0.029 0.0022 0.0011 0.09 0.10 0.09
EN031115_202247 N 220.875 51.46 21.69 29.92 2.262 0.8607 0.3152 298.38 3.73 159.24
0.07 0.06 0.10 0.030 0.0021 0.0012 0.13 0.08 0.13
EN031115_204226 SB 220.888 52.73 14.89 29.61 2.273 0.8564 0.3264 117.01 5.10 157.92
0.03 0.07 0.04 0.011 0.0008 0.0006 0.07 0.08 0.07
EN031115_212219 SB 220.916 52.99 14.75 29.75 2.278 0.8581 0.3231 117.37 5.40 158.30
0.04 0.03 0.09 0.027 0.0020 0.0010 0.08 0.04 0.08
EN031115_212455 SB 220.918 53.50 14.24 29.89 2.254 0.8588 0.3182 118.03 6.26 158.96
0.02 0.02 0.08 0.021 0.0016 0.0008 0.04 0.03 0.04
EN031115_213844 SB 220.928 52.78 14.81 29.60 2.272 0.8561 0.3269 116.95 5.21 157.90
0.11 0.03 0.05 0.023 0.0013 0.0014 0.21 0.06 0.21
EN031115_221917 SB 220.956 52.88 14.43 29.50 2.251 0.8539 0.3289 116.81 5.66 157.78
0.02 0.03 0.09 0.025 0.0020 0.0010 0.05 0.04 0.05
EN031115_221937 SB 220.956 52.99 14.90 29.71 2.268 0.8575 0.3232 117.39 5.20 158.37
0.01 0.03 0.03 0.009 0.0007 0.0004 0.04 0.04 0.04
EN031115_222446 SB 220.960 52.00 14.45 29.05 2.273 0.8487 0.3438 115.02 5.19 156.00
0.04 0.02 0.08 0.022 0.0017 0.0009 0.07 0.03 0.07
EN031115_225609 SB 220.981 53.44 14.98 30.02 2.277 0.8618 0.3148 118.32 5.36 159.32
0.02 0.07 0.05 0.015 0.0011 0.0007 0.06 0.09 0.06
EN031115_230149 SB 220.985 53.14 14.53 29.72 2.269 0.8574 0.3235 117.36 5.70 158.36
0.03 0.02 0.09 0.026 0.0020 0.0010 0.06 0.03 0.06
Article number, page 18 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Table 4. continued.
Code Branch1λαgδgvga e q ωiπ
EN031115_232829 SB 221.004 53.09 15.30 29.83 2.275 0.8595 0.3196 117.78 4.77 158.80
0.01 0.02 0.05 0.013 0.0010 0.0005 0.02 0.02 0.02
EN031115_235911 S 221.025 51.85 16.41 28.35 2.058 0.8324 0.3449 115.81 2.78 156.87
0.13 0.18 0.13 0.032 0.0030 0.0022 0.27 0.21 0.27
EN041115_012728 SB 221.087 52.76 14.08 29.26 2.245 0.8503 0.3360 116.01 5.95 157.12
0.02 0.01 0.03 0.009 0.0008 0.0004 0.04 0.02 0.04
EN041115_020201 SB 221.111 52.55 14.48 29.24 2.260 0.8508 0.3372 115.83 5.40 156.95
0.01 0.02 0.03 0.008 0.0006 0.0004 0.03 0.02 0.03
EN041115_021111 SB 221.117 53.60 14.77 29.98 2.274 0.8610 0.3160 118.20 5.65 159.33
0.05 0.03 0.04 0.012 0.0008 0.0007 0.09 0.05 0.09
EN041115_021452 SB 221.120 53.16 14.64 29.67 2.268 0.8568 0.3250 117.19 5.55 158.33
0.01 0.01 0.02 0.005 0.0003 0.0002 0.02 0.02 0.02
EN041115_043317 SB 221.216 53.10 14.11 29.48 2.269 0.8539 0.3315 116.44 6.10 157.67
0.02 0.02 0.04 0.010 0.0008 0.0005 0.04 0.03 0.04
EN041115_044559 SB 221.225 53.31 14.43 29.66 2.269 0.8564 0.3258 117.10 5.85 158.34
0.03 0.02 0.04 0.010 0.0008 0.0005 0.06 0.02 0.06
EN041115_203853 SB 221.888 54.05 14.80 29.71 2.260 0.8569 0.3234 117.40 5.64 159.30
0.02 0.05 0.05 0.015 0.0012 0.0006 0.06 0.06 0.06
EN041115_210403 SB 221.905 53.92 15.16 29.64 2.250 0.8559 0.3242 117.34 5.13 159.26
0.03 0.11 0.07 0.021 0.0016 0.0009 0.10 0.13 0.10
EN041115_214032 SB 221.931 53.58 14.86 29.43 2.267 0.8535 0.3321 116.37 5.30 158.32
0.03 0.02 0.07 0.020 0.0016 0.0008 0.06 0.03 0.06
EN041115_215226 SB 221.939 53.82 14.86 29.44 2.233 0.8526 0.3292 116.83 5.40 158.79
0.01 0.01 0.04 0.009 0.0008 0.0004 0.03 0.02 0.03
EN041115_225243 SB 221.981 53.66 14.61 29.37 2.258 0.8523 0.3335 116.24 5.61 158.24
0.02 0.03 0.10 0.028 0.0023 0.0011 0.05 0.04 0.05
EN041115_231355 SB 221.996 53.95 14.39 29.51 2.261 0.8541 0.3300 116.64 6.02 158.64
0.03 0.05 0.08 0.022 0.0018 0.0009 0.07 0.06 0.07
EN051115_023102 SB 222.133 53.96 14.96 29.45 2.241 0.8530 0.3295 116.77 5.32 158.91
0.01 0.03 0.02 0.006 0.0005 0.0003 0.03 0.03 0.03
EN051115_183559 S 222.804 53.24 13.90 28.48 2.259 0.8398 0.3618 113.02 5.93 155.84
0.01 0.02 0.01 0.004 0.0004 0.0002 0.02 0.02 0.02
EN051115_185259 SB 222.816 54.30 14.56 29.26 2.270 0.8510 0.3382 115.65 5.79 158.49
0.03 0.03 0.12 0.035 0.0028 0.0012 0.05 0.03 0.05
EN051115_190203 SB 222.823 54.34 14.66 29.30 2.270 0.8516 0.3371 115.78 5.70 158.62
0.02 0.02 0.03 0.010 0.0008 0.0004 0.03 0.02 0.03
EN051115_203651 SB 222.889 54.18 14.44 29.11 2.266 0.8487 0.3427 115.15 5.83 158.06
0.03 0.03 0.05 0.013 0.0010 0.0006 0.06 0.03 0.06
EN051115_205304 N 222.900 53.87 21.71 29.26 2.076 0.8461 0.3195 298.63 2.98 161.50
0.02 0.01 0.02 0.005 0.0004 0.0003 0.04 0.01 0.04
EN051115_212802 SB 222.924 54.21 14.94 29.06 2.235 0.8475 0.3409 115.48 5.26 158.42
0.02 0.04 0.04 0.011 0.0009 0.0005 0.05 0.04 0.05
EN051115_213128 SB 222.927 54.20 14.90 29.14 2.259 0.8492 0.3405 115.43 5.31 158.38
0.09 0.16 0.11 0.033 0.0024 0.0017 0.21 0.19 0.21
EN051115_213433 SB 222.929 53.79 14.60 28.83 2.255 0.8448 0.3499 114.38 5.43 157.32
0.01 0.02 0.03 0.007 0.0006 0.0003 0.02 0.02 0.02
EN051115_220108 SB 222.947 53.92 14.47 28.88 2.257 0.8455 0.3487 114.50 5.64 157.47
0.01 0.01 0.02 0.007 0.0006 0.0003 0.02 0.02 0.02
EN051115_221253 SB 222.956 54.30 14.77 29.13 2.252 0.8488 0.3404 115.47 5.50 158.44
0.05 0.02 0.03 0.011 0.0006 0.0007 0.11 0.03 0.11
EN051115_221501 N 222.957 51.92 21.71 28.80 2.253 0.8454 0.3484 294.60 3.32 157.53
0.01 0.01 0.08 0.021 0.0018 0.0008 0.02 0.02 0.02
EN051115_221906 SB 222.960 54.28 15.20 29.16 2.246 0.8493 0.3384 115.72 5.00 158.70
0.03 0.02 0.05 0.014 0.0012 0.0006 0.06 0.03 0.06
EN051115_225625 SB 222.986 54.09 14.54 28.99 2.262 0.8471 0.3458 114.81 5.65 157.81
0.01 0.04 0.03 0.008 0.0006 0.0004 0.04 0.05 0.04
EN051115_225852 S 222.988 53.90 15.19 28.53 2.150 0.8373 0.3498 114.83 4.74 157.84
0.01 0.01 0.04 0.010 0.0010 0.0005 0.02 0.01 0.02
EN051115_231201 SB 222.997 54.25 15.06 29.15 2.260 0.8495 0.3400 115.48 5.15 158.49
0.01 0.00 0.04 0.010 0.0009 0.0004 0.02 0.01 0.02
EN051115_232719 N 223.007 55.29 21.85 29.42 1.944 0.8445 0.3023 301.24 2.86 164.22
0.04 0.03 0.00 0.005 0.0001 0.0005 0.08 0.05 0.08
EN051115_234939 SB 223.023 54.18 14.47 29.01 2.263 0.8473 0.3454 114.86 5.76 157.90
0.01 0.01 0.05 0.012 0.0010 0.0005 0.02 0.01 0.02
Article number, page 19 of 24
A&A proofs: manuscript no. Spurny_Taurids
Table 4. continued.
Code Branch1λαgδgvga e q ωiπ
EN051115_235119 SB 223.024 54.53 14.98 29.35 2.274 0.8525 0.3353 115.96 5.39 159.00
0.01 0.01 0.08 0.023 0.0018 0.0009 0.02 0.02 0.02
EN061115_001740 SB 223.042 54.44 14.66 29.23 2.275 0.8508 0.3394 115.49 5.70 158.55
0.01 0.01 0.03 0.007 0.0006 0.0003 0.01 0.01 0.01
EN061115_002202 S 223.045 52.54 15.27 28.14 2.261 0.8362 0.3704 112.04 4.10 155.11
0.02 0.02 0.09 0.025 0.0022 0.0011 0.05 0.02 0.05
EN061115_003508 SB 223.055 54.24 15.36 29.15 2.256 0.8495 0.3395 115.55 4.79 158.62
0.03 0.05 0.07 0.018 0.0014 0.0008 0.07 0.06 0.07
EN061115_005009 S 223.065 54.31 15.97 29.26 2.251 0.8511 0.3350 116.08 4.13 159.16
0.04 0.13 0.12 0.033 0.0027 0.0015 0.12 0.15 0.12
EN061115_011233 SB 223.081 54.27 14.94 29.08 2.256 0.8484 0.3420 115.27 5.27 158.36
0.01 0.02 0.04 0.010 0.0008 0.0004 0.03 0.03 0.03
EN061115_011441 SB 223.082 53.57 15.17 28.72 2.263 0.8440 0.3530 113.99 4.67 157.09
0.09 0.05 0.10 0.029 0.0022 0.0015 0.19 0.06 0.19
EN061115_011623 SB 223.083 54.04 14.54 28.91 2.266 0.8462 0.3483 114.51 5.59 157.61
0.02 0.03 0.12 0.032 0.0027 0.0014 0.06 0.03 0.06
EN061115_025156 SB 223.150 54.42 14.65 29.17 2.279 0.8501 0.3417 115.22 5.67 158.38
0.22 0.03 0.08 0.041 0.0021 0.0027 0.43 0.09 0.43
EN061115_030548 S 223.160 54.69 16.07 29.54 2.276 0.8557 0.3284 116.74 4.18 159.92
0.02 0.03 0.05 0.014 0.0011 0.0007 0.05 0.04 0.05
EN061115_040629 SB 223.202 54.36 14.47 29.01 2.263 0.8473 0.3456 114.83 5.80 158.05
0.01 0.01 0.01 0.004 0.0003 0.0002 0.03 0.01 0.03
EN061115_164758 SB 223.732 54.85 14.88 28.94 2.240 0.8458 0.3455 114.93 5.45 158.68
0.00 0.01 0.01 0.002 0.0002 0.0001 0.01 0.01 0.01
EN061115_174311 SB 223.771 54.88 15.22 29.14 2.279 0.8499 0.3421 115.16 5.11 158.95
0.01 0.01 0.04 0.012 0.0009 0.0004 0.03 0.02 0.03
EN071115_015331 SB 224.112 54.80 14.66 28.71 2.260 0.8432 0.3543 113.84 5.58 157.97
0.04 0.02 0.12 0.030 0.0027 0.0014 0.09 0.03 0.09
EN081115_010613 SB 225.083 55.57 14.79 28.62 2.271 0.8422 0.3584 113.33 5.58 158.43
0.04 0.03 0.12 0.032 0.0028 0.0014 0.08 0.04 0.08
EN081115_033341 SB 225.186 55.71 14.71 28.57 2.257 0.8410 0.3589 113.33 5.69 158.53
0.04 0.06 0.11 0.028 0.0025 0.0014 0.10 0.07 0.10
EN081115_181258 SB 225.799 55.87 14.75 28.31 2.264 0.8377 0.3674 112.34 5.58 158.15
0.01 0.02 0.01 0.003 0.0003 0.0002 0.02 0.02 0.02
EN081115_202907 SB 225.894 55.47 14.56 28.02 2.274 0.8341 0.3774 111.17 5.55 157.08
0.02 0.02 0.07 0.021 0.0018 0.0008 0.04 0.02 0.04
EN081115_212839 SB 225.935 55.15 14.83 27.80 2.260 0.8307 0.3827 110.63 5.12 156.58
0.01 0.01 0.02 0.007 0.0006 0.0003 0.01 0.01 0.01
EN081115_234417 SB 226.030 55.75 14.48 28.02 2.254 0.8331 0.3761 111.39 5.72 157.43
0.03 0.02 0.08 0.021 0.0019 0.0009 0.05 0.02 0.05
EN091115_001801 SB 226.053 55.15 15.25 27.82 2.272 0.8318 0.3822 110.63 4.67 156.71
0.02 0.03 0.16 0.041 0.0038 0.0017 0.06 0.03 0.06
EN091115_003545 SB 226.066 55.43 15.02 27.91 2.261 0.8323 0.3791 111.02 5.01 157.11
0.05 0.02 0.03 0.011 0.0008 0.0007 0.09 0.03 0.09
EN091115_011246 SB 226.092 55.46 14.33 27.72 2.237 0.8282 0.3842 110.55 5.71 156.66
0.04 0.10 0.11 0.028 0.0026 0.0014 0.11 0.10 0.11
EN091115_011650 SB 226.094 55.36 15.19 27.87 2.258 0.8318 0.3799 110.94 4.80 157.06
0.02 0.03 0.12 0.029 0.0028 0.0013 0.04 0.04 0.04
EN091115_032502 SB 226.184 55.99 15.27 28.27 2.277 0.8379 0.3691 112.08 5.00 158.28
0.02 0.02 0.02 0.007 0.0006 0.0004 0.04 0.03 0.04
EN091115_041944 N 226.222 56.51 21.89 29.90 2.387 0.8639 0.3248 296.79 2.51 162.97
0.03 0.02 0.06 0.017 0.0012 0.0007 0.05 0.03 0.05
EN101115_212402 SB 227.942 56.75 15.16 27.47 2.242 0.8252 0.3918 109.66 5.03 157.62
0.03 0.03 0.05 0.015 0.0014 0.0007 0.07 0.03 0.07
EN101115_235401 SB 228.047 57.00 15.45 27.66 2.260 0.8287 0.3870 110.11 4.84 158.18
0.04 0.02 0.03 0.009 0.0007 0.0006 0.08 0.03 0.08
EN111115_004713 S 228.084 56.33 13.94 27.01 2.256 0.8187 0.4090 107.68 5.99 155.77
0.01 0.02 0.08 0.020 0.0020 0.0009 0.03 0.02 0.03
EN111115_031037 SB 228.184 57.37 14.70 27.64 2.248 0.8275 0.3880 110.06 5.71 158.26
0.12 0.23 0.06 0.026 0.0017 0.0019 0.29 0.24 0.29
EN111115_181413 SB 228.815 57.27 14.96 27.30 2.266 0.8236 0.3997 108.66 5.27 157.50
0.06 0.07 0.08 0.025 0.0021 0.0011 0.13 0.07 0.13
EN111115_181509 SB 228.815 57.11 15.06 27.20 2.262 0.8223 0.4021 108.41 5.10 157.24
0.03 0.03 0.00 0.004 0.0002 0.0003 0.05 0.03 0.05
Article number, page 20 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Table 4. continued.
Code Branch1λαgδgvga e q ωiπ
EN111115_184540 N 228.837 58.35 22.60 29.04 2.286 0.8494 0.3443 294.88 2.78 163.68
0.13 0.02 0.06 0.026 0.0015 0.0016 0.25 0.03 0.25
EN111115_203917 SB 228.916 56.93 14.97 27.08 2.277 0.8212 0.4072 107.77 5.09 156.71
0.12 0.04 0.05 0.023 0.0015 0.0015 0.24 0.05 0.24
EN111115_233243 SB 229.037 57.63 15.13 27.34 2.250 0.8235 0.3970 109.02 5.19 158.08
0.03 0.01 0.04 0.012 0.0011 0.0006 0.06 0.02 0.06
EN121115_004717 SB 229.089 57.10 15.23 26.97 2.242 0.8183 0.4074 107.90 4.85 157.01
0.03 0.04 0.07 0.017 0.0017 0.0008 0.07 0.04 0.07
EN121115_232341 S 230.037 56.31 14.51 25.93 2.262 0.8041 0.4431 103.82 5.00 153.88
0.02 0.05 0.05 0.014 0.0014 0.0007 0.05 0.04 0.05
EN131115_002058 SB 230.077 58.58 15.58 27.39 2.269 0.8251 0.3968 108.96 4.94 159.05
0.02 0.06 0.09 0.023 0.0022 0.0011 0.06 0.06 0.06
EN131115_004858 SB 230.097 58.41 15.35 27.27 2.275 0.8236 0.4013 108.42 5.09 158.54
0.02 0.02 0.09 0.023 0.0022 0.0011 0.05 0.02 0.05
EN131115_015008 SB 230.139 58.33 14.98 27.15 2.277 0.8219 0.4057 107.93 5.41 158.09
0.01 0.01 0.03 0.009 0.0008 0.0004 0.03 0.01 0.03
EN131115_042559 SB 230.248 58.11 15.37 26.98 2.270 0.8195 0.4097 107.51 4.91 157.77
0.09 0.02 0.08 0.024 0.0021 0.0015 0.17 0.03 0.17
EN161115_193458 S 233.906 60.56 14.63 25.65 2.162 0.7942 0.4450 104.03 5.66 157.95
0.03 0.01 0.02 0.007 0.0007 0.0004 0.06 0.01 0.06
EN161115_213048 SB 233.987 60.23 15.09 25.86 2.257 0.8025 0.4457 103.50 5.20 157.51
0.01 0.01 0.04 0.009 0.0010 0.0004 0.02 0.01 0.02
EN161115_222246 S 234.023 67.52 16.82 29.10 1.957 0.8372 0.3185 119.17 6.26 173.21
0.06 0.02 0.09 0.018 0.0019 0.0011 0.12 0.03 0.12
EN171115_020907 SB 234.182 60.80 15.58 26.20 2.273 0.8083 0.4357 104.54 4.94 158.74
0.02 0.08 0.00 0.004 0.0001 0.0004 0.06 0.08 0.06
EN171115_022102 SB 234.190 60.40 15.51 25.91 2.260 0.8036 0.4440 103.68 4.84 157.89
0.02 0.02 0.04 0.010 0.0010 0.0005 0.03 0.02 0.03
EN231115_012005 N 240.202 66.46 24.65 26.27 2.147 0.8035 0.4219 286.63 2.93 166.80
0.03 0.01 0.03 0.009 0.0009 0.0005 0.06 0.01 0.06
EN231115_224311 S 241.102 69.19 16.03 25.73 1.992 0.7853 0.4277 106.76 5.83 167.88
0.16 0.02 0.06 0.022 0.0019 0.0020 0.31 0.04 0.31
EN281115_195251 S 246.038 70.87 16.55 25.18 2.300 0.7936 0.4747 99.91 5.12 165.97
0.03 0.02 0.05 0.016 0.0016 0.0006 0.05 0.02 0.05
1N – Northern (13), S – Southern (18), SB – Southern new branch (113)
Article number, page 21 of 24
A&A proofs: manuscript no. Spurny_Taurids
Table 5. Physical data of 2015 Taurid fireballs. The entry velocity, heights of beginning, maximum brightness and end, average zenith distance of
the radiant, photometric mass, maximum absolute magnitude, PE coefficient, and classification according to PE are given. Code of each fireball
contains also date (in ddmmyy format) and GMT time corresponding to beginning rounded to whole second (in hhmmss format)
Code Branch v∞Hbeg Hmax Hend Zrad Mass Mag PE Type
km/s km km km deg kg
EN231015_204348 S 36.98 106.3 73.2 59.7 54.7 0.0055 -7.5 -4.52 I
EN231015_211327 N 32.30 96.9 64.9 57.8 38.2 0.0021 -4.2 -4.51 I
EN241015_004546 N 34.25 103.9 65.7 64.8 31.4 0.0022 -8.2 -4.89 II
EN241015_185031 S 30.58 98.8 73.9 65.6 67.3 0.012 -6.3 -4.87 II
EN251015_022301 SB 34.30 104.5 77.6 69.7 44.6 0.18 -12.0 -5.87 IIIB
EN251015_031725 SB 33.40 108.3 71.1 66.9 52.3 0.0011 -4.9 -4.71 II
EN261015_213736 SB 34.38 91.9 72.2 64.0 43.4 0.0048 -6.4 -4.90 II
EN261015_224031 SB 33.95 94.6 72.1 61.3 38.2 0.0041 -6.5 -4.78 II
EN271015_220749 SB 33.75 94.3 71.6 62.4 41.9 0.20 -10.5 -5.52 IIIA
EN281015_011855 S 28.87 90.1 77.9 65.8 42.8 0.0023 -5.0 -4.98 II
EN301015_222401 SB 32.98 104.0 67.5 65.5 38.9 0.0047 -8.9 -5.04 II
EN311015_002325 N 30.38 102.7 68.1 59.3 32.0 0.0037 -6.3 -4.77 II
EN311015_023900 SB 32.63 105.5 80.9 68.5 47.5 0.0055 -6.3 -5.17 II
EN311015_025717 SB 32.63 99.8 71.7 57.9 53.3 0.21 -11.5 -5.19 II
EN311015_172431 SB 33.05 102.0 87.4 81.9 76.5 0.0010 -3.5 -5.12 II
EN311015_180520 SB 33.06 114.7 80.8 57.6 72.1 1300 -18.6 -6.31 IIIB
EN311015_182902 SB 32.61 99.0 79.0 74.0 69.8 0.0005 -4.0 -4.66 II
EN311015_185530 SB 32.80 103.7 77.1 69.4 63.7 0.0006 -3.0 -4.55 II
EN311015_192126 S 31.90 99.9 69.9 69.5 62.6 0.0006 -3.5 -4.62 II
EN311015_200534 SB 32.76 100.3 76.7 67.2 52.2 0.0020 -5.1 -4.85 II
EN311015_202117 SB 32.43 105.7 60.3 55.2 53.5 0.0070 -8.0 -4.43 I
EN311015_211904 SB 33.08 102.8 75.5 71.3 46.8 0.039 -10.2 -5.68 IIIB
EN311015_230919 SB 32.78 100.2 69.9 64.1 33.6 0.0006 -3.8 -4.61 II
EN311015_231301 SB 32.56 120.0 74.4 57.3 36.9 34 -15.8 -6.19 IIIB
EN011115_013625 SB 32.41 98.8 69.0 58.2 41.0 0.021 -9.5 -4.92 II
EN011115_033911 N 32.92 101.2 74.7 71.6 54.0 0.0081 -9.4 -5.33 IIIA
EN011115_174410 SB 32.64 102.3 71.7 67.2 75.6 0.0089 -6.6 -4.62 II
EN011115_183646 S 32.55 95.0 82.3 80.1 65.8 0.0002 -2.4 -5.00 II
EN011115_191104 SB 32.24 104.3 78.4 73.8 63.4 0.0049 -4.1 -5.00 II
EN011115_200918 SB 32.47 93.2 64.5 61.3 53.2 0.0030 -6.9 -4.60 II
EN011115_223909 SB 32.52 102.2 76.5 62.8 37.3 0.0021 -4.6 -4.72 II
EN011115_234207 SB 32.60 96.3 71.5 57.6 31.3 0.0083 -7.5 -4.77 II
EN021115_020950 SB 32.05 99.8 77.0 69.7 45.1 0.0020 -6.1 -5.09 II
EN021115_021740 SB 32.00 94.0 74.9 68.2 45.1 0.0008 -4.2 -4.83 II
EN021115_022525 SB 32.38 107.5 75.2 63.3 45.3 0.20 -10.9 -5.57 IIIA
EN021115_024553 N 29.72 99.9 59.3 53.9 47.5 0.027 -7.8 -4.68 II
EN021115_182450 SB 31.93 94.9 72.7 62.7 71.2 0.031 -7.8 -4.76 II
EN021115_195540 SB 32.46 100.8 79.0 75.1 55.8 0.0018 -5.3 -5.25 IIIA
EN021115_201534 SB 32.19 102.9 76.5 72.1 53.6 0.0002 -2.1 -4.73 II
EN021115_205431 N 33.00 111.9 76.5 73.8 42.9 0.0003 -3.2 -4.98 II
EN021115_213614 SB 32.17 97.5 70.8 60.7 45.4 0.15 -11.3 -5.37 IIIA
EN021115_215818 SB 32.16 99.5 77.0 73.3 40.8 0.0017 -6.7 -5.31 IIIA
EN021115_220435 SB 32.11 108.6 70.8 63.6 39.3 0.0010 -6.1 -4.68 II
EN021115_232112 SB 31.80 94.4 54.1 48.4 35.5 0.015 -9.3 -4.39 I
EN021115_234348 S 30.66 100.5 78.5 70.9 32.8 0.0001 -1.9 -4.78 II
EN021115_235259 SB 31.98 100.5 62.9 58.9 33.2 0.0031 -7.5 -4.68 II
EN031115_002007 SB 31.78 101.9 73.3 58.7 35.1 0.0004 -3.0 -4.28 I
EN031115_011247 SB 32.10 98.8 81.0 67.4 37.9 0.0003 -2.6 -4.67 II
EN031115_012404 SB 31.87 97.6 71.6 61.1 41.9 0.0015 -4.3 -4.59 II
EN031115_025102 SB 31.85 99.8 73.0 69.1 48.4 0.0004 -3.0 -4.71 II
EN031115_031920 SB 31.43 97.5 81.5 71.3 56.1 0.0005 -3.2 -4.80 II
EN031115_193751 SB 31.99 102.6 80.3 69.9 57.8 0.0053 -6.4 -5.12 II
EN031115_195654 SB 32.13 97.7 69.1 68.4 54.6 0.0055 -9.1 -5.09 II
EN031115_202247 N 32.12 94.4 79.1 72.8 44.5 0.0008 -4.2 -5.12 II
EN031115_204226 SB 31.84 100.9 65.9 59.2 51.0 0.0013 -4.9 -4.37 I
EN031115_212219 SB 31.92 96.5 69.6 68.1 42.1 0.0017 -6.7 -4.99 II
EN031115_212455 SB 32.04 99.1 64.8 59.8 41.7 0.013 -9.8 -4.92 II
Article number, page 22 of 24
P. Spurný et al.: Discovery of a new branch of the Taurid meteoroid stream
Table 5. continued.
Code Branch v∞Hbeg Hmax Hend Zrad Mass Mag PE Type
km/s km km km deg kg
EN031115_213844 SB 31.77 101.5 72.7 66.8 42.9 0.0029 -6.5 -5.01 II
EN031115_221917 SB 31.63 101.6 83.8 74.6 38.5 0.0003 -2.9 -5.08 II
EN031115_221937 SB 31.82 98.9 64.6 59.9 39.6 0.0047 -7.7 -4.77 II
EN031115_222446 SB 31.19 100.8 72.9 69.4 36.2 0.0003 -2.6 -4.78 II
EN031115_225609 SB 32.06 95.9 72.0 61.7 35.7 0.0008 -3.8 -4.57 I
EN031115_230149 SB 31.78 99.1 74.5 66.1 33.1 0.0010 -4.7 -4.85 II
EN031115_232829 SB 31.85 98.6 69.5 59.2 34.9 0.0030 -7.0 -4.68 II
EN031115_235911 S 30.41 98.1 76.1 66.8 30.1 0.012 -8.4 -5.40 IIIA
EN041115_012728 SB 31.16 106.5 63.7 48.1 39.5 0.0018 -4.1 -3.97 I
EN041115_020201 SB 31.10 98.1 63.9 58.1 45.9 0.0033 -6.3 -4.56 I
EN041115_021111 SB 31.80 100.2 71.7 67.2 42.5 0.44 -12.7 -5.96 IIIB
EN041115_021452 SB 31.50 102.8 68.4 63.8 45.1 0.0076 -8.8 -5.01 II
EN041115_043317 SB 31.22 101.8 83.0 75.3 65.7 0.0005 -3.0 -4.88 II
EN041115_044559 SB 31.39 100.1 82.7 75.4 65.8 0.0005 -2.6 -4.89 II
EN041115_203853 SB 31.90 95.0 74.9 60.2 48.2 0.21 -10.6 -5.39 IIIA
EN041115_210403 SB 31.81 98.7 64.7 62.9 45.1 0.031 -10.1 -5.21 II
EN041115_214032 SB 31.58 94.1 68.2 56.2 38.3 0.016 -9.8 -4.81 II
EN041115_215226 SB 31.60 93.9 64.2 52.6 40.1 0.0032 -4.2 -4.29 I
EN041115_225243 SB 31.45 97.3 67.9 60.4 35.4 0.0015 -5.6 -4.61 II
EN041115_231355 SB 31.56 92.3 71.7 63.5 35.5 0.019 -9.2 -5.25 IIIA
EN051115_023102 SB 31.27 98.0 65.7 56.9 47.8 0.011 -8.8 -4.69 II
EN051115_183559 S 30.84 99.9 68.3 65.3 67.2 0.0087 -7.8 -4.80 II
EN051115_185259 SB 31.57 99.7 79.6 75.7 64.4 0.0004 -3.3 -4.88 II
EN051115_190203 SB 31.61 99.6 78.5 72.5 63.0 0.0008 -3.6 -4.85 II
EN051115_203651 SB 31.35 101.1 71.7 66.3 47.6 0.0010 -6.3 -4.76 II
EN051115_205304 N 31.46 103.5 70.0 57.4 38.5 0.093 -10.4 -5.20 II
EN051115_212802 SB 31.27 96.5 72.3 65.5 43.7 0.0016 -4.7 -4.84 II
EN051115_213128 SB 31.32 91.4 70.8 66.3 43.7 0.090 -10.5 -5.62 IIIA
EN051115_213433 SB 31.03 105.9 62.2 58.1 41.0 0.0038 -7.4 -4.63 II
EN051115_220108 SB 31.05 99.3 70.8 66.0 38.9 0.050 -10.0 -5.54 IIIA
EN051115_221253 SB 31.28 102.4 64.7 60.9 36.6 0.010 -9.6 -4.99 II
EN051115_221501 N 30.95 107.8 77.0 70.8 29.9 0.0005 -3.9 -5.02 II
EN051115_221906 SB 31.28 96.7 76.3 67.6 35.5 0.0006 -4.0 -4.84 II
EN051115_225625 SB 31.10 99.9 76.7 71.2 35.2 0.0003 -3.1 -4.90 II
EN051115_225852 S 30.66 98.7 73.3 63.7 34.9 0.0019 -5.7 -4.85 II
EN051115_231201 SB 31.22 105.3 72.0 62.1 32.3 0.11 -11.0 -5.52 IIIA
EN051115_232719 N 31.48 101.0 71.0 64.6 25.4 0.0018 -6.2 -4.94 II
EN051115_234939 SB 31.05 102.5 61.5 57.0 34.2 0.0026 -6.5 -4.56 I
EN051115_235119 SB 31.37 99.3 73.7 63.7 33.4 0.0019 -6.8 -4.85 II
EN061115_001740 SB 31.20 104.8 68.5 61.1 35.2 0.0044 -7.8 -4.86 II
EN061115_002202 S 30.20 102.2 62.9 54.0 33.4 0.0009 -4.3 -4.22 I
EN061115_003508 SB 31.10 100.4 66.6 65.3 36.5 0.0052 -9.1 -5.11 II
EN061115_005009 S 31.20 94.2 74.4 64.2 37.9 0.0045 -7.8 -5.01 II
EN061115_011233 SB 31.02 98.9 60.1 57.5 38.5 0.0031 -8.1 -4.58 I
EN061115_011441 SB 30.67 98.9 83.6 71.9 37.0 0.0003 -3.4 -4.94 II
EN061115_011623 SB 30.85 97.2 69.0 64.5 39.9 0.0004 -2.9 -4.57 I
EN061115_025156 SB 30.98 94.5 77.5 73.2 50.1 0.0026 -5.0 -5.31 IIIA
EN061115_030548 S 31.33 98.8 75.9 71.7 51.5 0.0020 -7.3 -5.15 II
EN061115_040629 SB 30.78 101.1 71.1 65.0 63.3 0.0100 -8.2 -4.89 II
EN061115_164758 SB 31.28 104.0 79.7 74.0 83.3 0.0098 -5.1 -4.64 II
EN061115_174311 SB 31.47 99.6 79.8 76.5 73.3 0.0018 -4.2 -4.99 II
EN071115_015331 SB 30.60 104.4 76.7 59.0 43.7 3.6 -13.8 -5.92 IIIB
EN081115_010613 SB 30.59 92.4 78.7 71.5 37.9 0.0014 -5.9 -5.23 II
EN081115_033341 SB 30.41 96.4 72.3 70.0 57.5 0.0017 -5.3 -4.95 II
EN081115_181258 SB 30.69 99.1 65.9 65.6 70.2 0.049 -9.8 -5.05 II
EN081115_202907 SB 30.35 100.2 68.1 66.6 50.0 0.0020 -6.3 -4.90 II
EN081115_212839 SB 30.08 103.1 68.3 57.6 41.3 0.0022 -5.0 -4.52 I
EN081115_234417 SB 30.10 99.4 70.9 63.4 33.0 0.0062 -7.9 -5.08 II
EN091115_001801 SB 29.90 102.9 77.6 72.4 33.3 0.0009 -5.2 -5.25 II
Article number, page 23 of 24
A&A proofs: manuscript no. Spurny_Taurids
Table 5. continued.
Code Branch v∞Hbeg Hmax Hend Zrad Mass Mag PE Type
km/s km km km deg kg
EN091115_003545 SB 29.97 96.2 69.0 53.2 33.5 0.041 -9.3 -4.85 II
EN091115_011246 SB 29.73 88.7 75.7 70.3 40.5 0.0015 -5.0 -5.15 II
EN091115_011650 SB 29.88 98.4 76.5 71.4 38.5 0.0003 -3.3 -4.96 II
EN091115_032502 SB 30.13 99.6 78.8 73.4 54.7 0.0015 -4.5 -5.18 IIIA
EN091115_041944 N 31.62 99.3 73.9 67.8 61.1 0.0052 -8.5 -4.95 II
EN101115_212402 SB 29.77 102.4 63.5 58.4 41.5 0.011 -9.6 -4.86 II
EN101115_235401 SB 29.75 98.1 71.7 66.3 33.5 0.12 -10.9 -5.78 IIIB
EN111115_004713 S 29.11 97.3 63.9 56.9 35.8 0.022 -9.6 -4.97 II
EN111115_031037 SB 29.55 95.0 71.6 65.9 54.8 0.91 -13.5 -5.92 IIIB
EN111115_181413 SB 29.76 97.2 72.0 62.1 66.6 0.23 -11.4 -5.26 IIIA
EN111115_181509 SB 29.66 98.5 74.1 69.2 65.3 0.27 -11.8 -5.70 IIIB
EN111115_184540 N 31.36 102.0 65.9 72.0 59.4 0.0010 -3.3 -4.92 II
EN111115_203917 SB 29.47 93.5 77.6 74.5 46.5 0.0010 -3.8 -5.29 IIIA
EN111115_233243 SB 29.51 98.9 68.1 60.1 32.4 0.014 -8.3 -5.07 II
EN121115_004717 SB 29.07 96.9 74.4 71.6 36.9 0.0008 -5.4 -5.17 II
EN121115_232341 S 28.20 95.7 74.2 66.6 33.8 0.0005 -3.4 -4.83 II
EN131115_002058 SB 29.48 97.4 77.4 66.1 36.0 0.0074 -8.2 -5.25 IIIA
EN131115_004858 SB 29.34 94.5 79.2 67.7 35.8 0.0003 -2.3 -4.76 II
EN131115_015008 SB 29.17 103.1 74.7 61.2 43.8 0.0014 -5.0 -4.63 II
EN131115_042559 SB 28.90 93.7 75.9 74.2 64.1 0.0009 -3.5 -5.01 II
EN161115_193458 S 28.19 101.5 60.8 56.0 53.5 0.0079 -6.1 -4.58 I
EN161115_213048 SB 28.28 100.4 70.5 59.4 39.6 0.017 -10.1 -5.05 II
EN161115_222246 S 31.25 97.9 74.3 69.1 35.2 0.0004 -3.6 -4.86 II
EN171115_020907 SB 28.26 93.5 68.8 62.0 46.6 0.0062 -6.2 -4.93 II
EN171115_022102 SB 27.98 95.1 66.2 59.0 47.5 0.049 -10.6 -5.16 II
EN231115_012005 N 28.37 93.2 64.7 57.5 33.2 0.0040 -5.8 -4.72 II
EN231115_224311 S 28.06 96.8 68.5 57.0 31.7 0.074 -10.3 -5.25 II
EN281115_195251 S 27.74 108.0 78.2 64.7 50.3 0.0016 -4.1 -4.80 II
Article number, page 24 of 24
