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Jovian impact flashes detection with DeTeCt software project

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Observations of Jupiter by a large number of amateurs have resulted in the discovery of three fireballs in its atmosphere produced by the impacts of small objects. The fireballs were detected on. There could be more impacts undetected on amateur videos. Hence we propose tools for detecting impacts on existing videos and a project for collecting information on these analysis in order to constraining the estimation of detectable jovian impacts rate (see [1])
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Jovian impact flashes detection with DeTeCt software
project
M. Delcroix (1) and R. Hueso (2)
(1) Commission des observations planétaires, Société Astronomique de France (delcroix.marc@free.fr) (2) Departamento
Física Aplicada I, Universidad del País Vasco UPV/EHU, ETS Ingeniería, 48013 Bilbao (Spain) (ricardo.hueso@ehu.es)
Abstract
Observations of Jupiter by a large number of
amateurs have resulted in the discovery of three
fireballs in its atmosphere produced by the impacts of
small objects. The fireballs were detected on June 3,
2010, August 20, 2010 and September 10, 2012.
There could be more impacts undetected on amateur
videos. Hence we propose tools for detecting impacts
on existing videos and a project for collecting
information on these analysis in order to constraining
the estimation of detectable jovian impacts rate (see
[1])
1. Introduction
Prior to these 2010 and 2012 events, amateurs were
not aware of the possibility of detecting the flashes of
such impacts on their videos. Furthermore, for each
of these events, one amateur detected the flash and
issued an alert, leading other amateurs to detect the
flash afterwards on their own videos. Given the fact
that 3 fireball impacts have already been detected,
there is a possibility of having undetected impacts in
existing amateur videos.
A project called «DeTeCt» coordinating the search
for such undetected impacts has been launched, with
first preliminary results which could be used.
2. Data
2.1 Amateur participation
Planetary imaging amateurs use mostly reflectors
with an aperture from 15 to 40 cm. Since 2001, their
image coverage has been very good 6 months around
Jupiter’s opposition. There are several hundreds of
amateurs regularly observing Jupiter and in contact
with amateur associations like BAA, SAF, ALPO, …
The DeTeCt project already collected the analysis of
20 planetary imaging amateurs (see Table 1).
Table 1: List of amateurs participating the most to the
“DeTeCt” project (as of May 2013)
Name/
Country
Duration of
videos analysed
Time frame
Trevor Barry
(Australia)
1d 14h 43m 54s
(2424 videos)
2009/07/07 to
2012/12/30
Marc Delcroix
(France)
1d 9h 20m 0s
(1393 videos)
2006/04/14 to
2013/03/09
Pascal Bayle
(France)
0d 16h 47m 54s
(1006 videos)
2012/11/30 to
2013/03/03
Paul Rolet
(France)
0d 12h 43m 47s
(442 videos)
2012/09/07 to
2013/03/09
Pascal Lemaire
(France)
0d 10h 46m 56s
(573 videos)
2012/08/01 to
2013/02/16
Flavius Isac
(France)
0d 7h 47m 23s
(546 videos)
2011/08/12 to
2013/02/17
Christophe
Pellier (France)
0d 7h 38m 54s
(311 videos)
2012/02/20 to
2013/01/16
Manos Kardasis
(Greece)
0d 5h 12m 59s
(323 videos)
2010/06/09 to
2013/04/11
Xavier Dupont
(France)
0d 4h 21m 57s
(220 videos)
2012/08/16 to
2012/11/14
2.2 Detection method
The software used , called “DeTeCt”, can work on all
different types of videos/individual files that
amateurs use (avi, wmv, ser video formats; fits, tiff,
bmp, jpg, … file formats). It runs in a batch mode for
processing in a row all videos recursively found in a
directory and its sub-directories, easing the
processing of hundreds of acquisitions. Its’
development has been launched by the professional
planetary team in Bilbao but was extended for the
project with additional supported formats,
functionalities and logging capabilities by an amateur
(MD).
It works by first registering the frames of the video
images to align all frames canceling shifts due to
turbulence or drifts of the planet on the sensor. Then
it performs two operations. The first one attempts to
detect impacts automatically by identifying zones on
the planet getting sudden brightness increases which
are limited in time and spread on several pixels. The
second one generates a detection image constructed
by the difference between an image constructed with
the maximum value for each pixel in all frames and a
mean image constructed with the mean value for
each pixel in all frames. The histogram of this
detection image is stretched to the maximum to ease
the detection of a potential impact by a quick 1-2s
visual inspection by an amateur (see Figure 1).
Figure 1: detection image generated by DeTeCt
software (image with maximum value minus mean
value for each aligned pixel) from an acquisition
from Christopher Go on June 3rd 2010 with a ream
detected impact
The amateur has to analyze all detection images
generated (Complete and comprehensive English
and French tutorials for running the software and
analyzing the results are available in the website of
this project,
http://www.astrosurf.com/planetessaf/doc/project_det
ect.shtml ), then send to the author the log files
generated listing all analyzes done signaling any
potential positive result.
2.3 Additional information
Additional information is collected/processed for all
videos processed: start/mid/end time, duration,
frames per second. This information is derived either
by the acquisition software used by the amateur (all
common ones are supported: Lucam Recorder,
Genika, Firecapture, PLxCapture, Avi felopaul,
Genicap), or the file itself. This is used to calculate
the total duration of all videos processed from all
observers by a developed script analyzing all logs
generated.
3. Results
3.1 Number of impacts detected
As of may 2013, no impacts were detected yet within
this project.
3.2 Jupiter coverage analysed
As of May 2013, more 6h 1d 41m worth of videos,
from 7826 videos from 20 observers, acquired
between April 2006 and April 2013 were analyzed.
3.3 Rate of impacts
From this preliminary result we could estimate that
the detectable jovian impacts rate should be lower
than 1 per 60 earth days.
4. Summary and Conclusions
Amateurs can participate and run successfully by
their own a project for impact detection leading to a
first probable constraint to the estimation of
detectable jovian impacts rate (<1 per 60 earth days).
There is still a strong potential for getting more data
from more observers (some participants did not
analyze all of their available videos, and furthermore
the French community participated well but only a
few international amateurs participated yet). This
should be continued for the upcoming apparitions to
continue to actively contribute to impact detections
studies and refine the flux of impacts in Jupiter
estimation.
Acknowledgements
We would like to thank all amateurs who have been
participating to this project by analyzing their videos
and providing the results.
References
[1] Hueso R. et al.: The flux of impacts in Jupiter: From
superbolides to large-scale collissons, EPSC2013-228,
2013
... There could be more impacts still undetected on stored amateur videos. Hence, a project was developed called DeTeCt with software and database to search for fireballs on existing videos (Fig. 13), in order to constrain the rate of detectable Jovian impacts [61,62]. As of the writing of this paper (January 2015), more than 25.4 days total time of videos (from 25758 videos from 41 observers acquired between February 2004 and January 2015) were analyzed. ...
... dating the surfaces of the Galilean moons, and better estimation of the small-body population in the outer solar system). Consequently, there is no doubt that PRO-AM collaborations contribute actively to the scientific study of the impacts on Jupiter [59], [61]. [60] (South is up). ...
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