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The Evpatoria Messages

  • SETI League
  • Ministère de la Santé et des Services sociaux, Québec, Canada

Abstract and Figures

In 1999, an international team, led by an American private interest, had been assembled with a single goal : the broadcast a message to the stars. The preamble as been written by the authors based on some notions of information theory and on anti cryptography. This message was later broadcasted from a Russian Deep-Space Radar installation in Ukraine. A similar messages was broadcasted 4 years later.
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Dumas, Dutil
The Evpatoria Messages
and Y.Dutil
Dépt. de physique, de génie physique et d'optique
et Observatoire du mont Mégantic
Université Laval
In 1999, an international team, led by an
American private interest, had been assembled with a
single goal : the broadcast a message to the stars. The
preamble as been written by the authors based on
some notions of information theory and on anti
cryptography. This message was later broadcasted
from a Russian Deep-Space Radar installation in
Ukraine. A similar messages was broadcasted 4 years
active-seti, message construction, Evpatoria
The authors are Canadian scientists who were
involved in the design of both Cosmic Calls, which take
place on May 24th, 1999 and on June 6th, 2003. Those
were the third and fourth radio messages ever sent to an
eventual extra-terrestrial civilisation. The first one has
been carried by Frank Drake from the Arecibo radar in
1974 and the second by Jean-Marc Philippe from Nançay
in 1987.
Trying to communicate with an extra-terrestrial
civilisation is a daunting task by any standard. Not only
distances are colossal, but also we don’t know who and
where is our correspondent. There is not much information
about how to communicate with him either. Technological
limitations dictate the use of a radio transmission as the
best medium of communication. Radar transmitters of
Arecibo and Goldstone would have been very good for
this project, but they were unavailable. Fortunately, after a
long search, we discovered a Russian planetary radar,
which was up to the task and open for business. The
Evpatoria radar combines a 70-m antenna with a 150-kW
transmitter. The characteristics of the Ukrainian based
system fixed many parameters of the message. The
wavelength was fixed 6 cm, far from the mythical 21 cm
but still in the interstellar telecommunication window
(between 1 and 10 GHz).
Numerous interstellar sources of noise exist and
a radio transmission (depending on the carrier
wavelength) will be surely affected by it. It is difficult to
prevent the signal degradation. However, some solutions
are possible to maintain the level of information.
The message itself (i.e. the content) must be
written with a high redundancy. The information must be
repeated through the entire message. Some concepts are
even introduced using different approaches.
A communication system has a maximum error-
free channel capacity1 given by
where W is the bandwidth, S the signal power and N the
noise power.
Obviously, wider the bandwidth more efficient
is the communication. This leaded some authors to
consider that advanced civilizations may use wide band
signal to communicate with us2. Unfortunately, such
wideband signal would be nearly impossible to
differentiate from noise. Therefore, narrow band signal is
expected at least to establish the first contact3,4.
The other way to increase the communication
channel efficiency is to reduce the signal to noise ratio
(S/N). However, lowering the signal to noise ratio also
increases the bit error rate. At very low signal to noise
ratio, the message can be totally undecipherable. And
beyond the simple repetition of the message ad
infinitum5, there is other ways of fighting the noise. In
particular, error-correcting schemes could be embedded
in the message6.
The problem of noise resistance can be divided
into two subjects: the container (i.e. carrier wave and the
format) and the content (i.e. the information it-self).
A simple approach when using a bitstream type
of communication channel is to send a 1-D message.
Typically made from a series of 0 and 1's. One can
imagine the ASCII code or the MORSE code as example.
This fashion of sending information is quite
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Dumas, Dutil
useful and optimized for the bandwidth. However, it
requires a protocol (i.e. check sums, parity) to ensure a
high signal-to-noise ratio and a good understanding of the
Furthermore, the sending and the receiver must
agree on the specific on that protocol else no information
can be transmitted between them,
There is an alternative to the 1-D simple bitstream
approach and it is the use of a 2-D technique (i.e. images).
It is a more robust way of communication but requires
some preparation (i.e. the need of a format) to ensure that
the receiver will be able to understand the information.
Images are sent via their decomposition in lines
and then through a bitstream. Again the problem of
protocol is raised. However, the authors propose a solution
to eliminate the need of a protocol when sending images.
This will be discussed in a later section.
An image, as a carrier of information, provides us
with the potential to send more information while using
the bandwidth of a bitstream. The image is constituted of
pixels (i.e. 0 or 1). As such, a pixel can only hold one bit
of information. However, used as a group of NxM pixels,
more information can be sent (i.e. characters, drawing,
schematics, etc).
The authors have built a set of characters to
facilitate the coding of the message. Each character is a
small bitmap of 5x7. The patterns were carefully selected
by a computer algorithm to ensure that each symbol is to
be different from any other by a series of transformations
such as : mirroring and rotation. The selection of 5x7 was
done to optimize the spatial content of the message.
Smaller characters would not have given a great deal of
choices while larger would have taken too much place.
This set of characters is necessary to minimize
possible sources of error while decoding the message. To
illustrate the need for those criteria just look at the regular
alphabet. Group of letters such as p-q, b-d and a-e-o, are
too similar, could be confusion with each other in a noisy
context. We want to avoid such possibilities.
Also, with enough bit difference between them it
could be possible to read the whole message even with a
lot of noise.
The alphabet can be compared to the ancient
Egyptian hieroglyph system. Some characters represent a
single idiom such as numbers or mathematical operators
while others carried a more complex concept such as mass
and length. Table I shows an example of the 1999
Table I. sample of the 1999 alphabet
symbol meaning
the number 1
the number 5
symbol "+"
symbol "="
The alphabet is grouped into separate classes of
symbols as listed in Table II.
Table II. sample of the 1999 alphabet
class description
numbers single numbers from 0 to 9
mathematics operators, =, , and some
other concepts
units units of measurement such
as kg and meter.
chemistry a short list of chemical
physics concepts of physics such
as mass, energy, velocity,
biology some biology concepts
astronomy symbols of planets
other a series of miscellaneous
symbols used throughout
the message.
This coding scheme should allow the message to
be read even if 10% of the bits transmitted are erroneous.
The reconstruction of an image from a bitstream
is relatively simple. Even if the dimensions of such an
image is not known a priori.
A Fourier analysis and a folding algorithm can
be used to recreate the image providing that the image
has some repetitive features.. For this purpose, we have
encircled each page by a 1-pixel frame. The spectrum of
the bitstream reveals a structure like a comb which is the
signature of that frame.
To increase our chances of detection, we had to
carefully choose the destinations. Such a task was quite
difficult because we did not know much about the
favourable conditions to the formation of Earth-like
planets and of the apparition of life. Therefore, the target
selection was an educated guest based on the following
criteria :
The targets must be visible for long periods
from the Evpatoria Observatory ( > 15 degrees)
They should be near the galactic plane where
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Dumas, Dutil
the density of solar-like stars is maximum7 (l < 90
degrees and |b| < 15 degrees). This is also
supported by the META search if their candidates
are genuine signals8.
Over long range (~ 1 kpc), scintillation should be
minimized9 (l ≥ 50 degrees).
Stars listed in the SETI Institute's target catalogue
that fulfil the previous requirements were selected
Further selection bases on spectral type, duplicity,
metalicity and age reduced even more the list.
In 1999, we had just enough allocated time to
transmit in the direction of four stars with three repetitions
for each of them. In order to keep a descent signal to noise
ratio with our transmission rate (i.e. 100 bit/s), target stars
needed to be nearer than 100 light-years, even if our
correspondent was listening to us with an antenna of one
kilometre in diameter. From the list compiled by the SETI
Institute, we picked up the stars, which can be observed
easily from Ukraine. We focus our selection on stars near
the galactic plane, simply because basic calculations show
than the signal will reach an additional ten sun-like stars
(plus many more cooler ones) beyond our primary targets.
In fact, the signal may still be detected as far as 10,000
light-years by a 1-km antenna.
We also choose a region of the sky where the
interstellar scintillation is minimal, between 60 and 90
degrees of the galactic centre. The final selection was
made using spectral type, metallicity and age as criteria
(Kevin Apps, University of Sussex, gave us a crucial help
for this final step). We even managed to get a star in
bonus, since our target star 16 Cygni A has a widely
separated companion 16 Cygni B, which is know to
possess an extrasolar planet.
Table III. list of target stars for the 1999 message
name Spectral
HD178428 G5V 68.3
HD186408 G2V 70.5
HD1900360 G6IV+ 51.8
HD190040 G1V 57.6
The message is a set of 23 pages, each one of
127x127 pixels. The first page is shown in Figure I.
Figure 1. page 1 of the 1999 message.
As for the message content, the whole concept
was resumed by Hans Freudenthal10, who wrote in its
book Lincos: “In the beginning, we shall communicate
facts which may be supposed to be known to the
receiver”. Subjects like Mathematics and basic Physics
are very likely to be universal. It can be argued that an
extra-terrestrial civilisation may not know Physics at all
and their Mathematics might be quite different of our.
However, a race able to received our message would
have built a huge radiotelescope-like structure. It would
probably have some kind of serious search for other
intelligent civilisations. Therefore, it is quite difficult to
imagine how this could be done without Mathematics
and Physics.
So the message starts by teaching them how to
count. Like on the Rosetta stone, three separate
representations are used: groups of points, binary
representation and our special symbols. The base 10 is
used because it facilitates the writing and proof reading
of the message. The lower part of the first page is a list of
prime numbers. This short list ends with the largest prime
found so far 23,021,377-1. In the following pages, basic
Mathematical operators are described, which will be used
through out the rest of the message.
The last page of the Mathematical section
describes basic geometry. A circle is used to introduce
the notion of circumference and area, and the
transcendent number . Only the first 7 digits are written,
followed by “...” (which has been introduced previously)
and the last 15 digits. Those are the last of
51,539,600,000 digits found recently, and the sequence
should be recognized as such. The Pythagoras theorem is
also presented. It reinforces the notions of exponents and
The next logical step is the introduction of
physical concepts such as mass, length and time. It starts
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Dumas, Dutil
with a description of the hydrogen atom. Following that,
the helium and the neutron are presented. A description of
a sets of 12 atoms based on their number of protons and
neutrons is next. This list includes the element #112;
recently produced by a group of Russian scientists at the
time of we wrote the message. The mass is defined using
the 12C atom and the Avogadro number. Follows the
hydrogen spectrum from which the units of time and
length are introduced At that point any physical definition
can be derived from those basic notions (i.e. acceleration,
temperature, pressure, etc)
Diagrams are used to describe these physical
objects and it can be correctly argue than someone with a
different culture may not understand them. The authors
solve this problem by the use of fundamental ratios. For
example, it is known that the proton is 1836 more massive
then the electron and has an inverse charge. An extra-
terrestrial scientist may not use the Bohr description of the
hydrogen atom, but will certainly know the ratio of the
mass between the proton and the electron.
In order to provide some information about us, a
brief description of the Solar System, the Earth and the
Moon is inserted. This is also an opportunity to reinforce
the notions of time and length using the orbit of planets, if
the receiver has access to this information from its own
astronomical observations.
The message talks also about the humans
populating the third planet from the star. A drawing of a
man and a woman is shown along with a rule giving the
height of a human. A description of our visual and auditive
capacities is also given. Also, a schematics of the DNA
and a cell is given. This kind of data could be very useful
to introduce our type of life form.
The last part of the message presents a map of the
Earth and some information about the signal itself. The
authors give some information about cosmology and our
evaluation of the age of the universe. This last step along
with the largest prime, and the element #112 shows that
the human have enough resources at our disposition to go
beyond survival and pursue scientific research simply for
the knowledge.
In the last page, there ae some interesting
questions the author would like to be answered by the
receiving civilisation.
Protocols exist in the case of reception and it is
not permitted to send an answer. However, there is no
protocol preventing a deliberate sending of message.
Based on the article XI of the Outer Space Treaty,
many tentatives to inform the following organisations have
been made:
Committee on the Peaceful Uses of Outer Space
International Telecommunication Union
Committee on Space Research of the
International Council of Scientific Unions
International Academy of Astronautics
Commission 51 of the International
Astronomical Union
Commission J of the International Radio
Science Union
International Council for Science
Inter-Union Commission on Frequency
Allocation for Radio Astronomy and Space
No one reacted and every one let us transmit the
message without any interference.
However, in Canada, a letter by the authors to
the government has been leaked into the media which
had produced the following reactions :
"Canadian Defence Department Scientists On
Alien Alert!" (National Post, February 2nd,
"UFO chasers asked not to e-mail aliens" (CBC
News, November 10th 2000)
A second broadcast was performed in 2003. The
message has been modified and include some changes.
The format is no longer 23 pages but a single long page.
During post-analysis of the 1999 message, it was found
that vertical lines are more important for decoding than
horizontal. This modification gave the authors the
possibility to rearrange the whole text to be more space
The binary digits were kept as separators
between sections. On the right side, the value decreases
while it increases on the left. They count the number of
lines. The could be used to know is part of the message is
Figure 2. section 1 of the 2003 message.
Some items were dropped and some were added
for clarity but basically it is the same content. Element
112 (ununbium) was replaced by the element 114
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Dumas, Dutil
The whole set of characters was rebuilt to be
more resistant to noise. The 5x7 symbols was replaced by
a 4x7 symbols for digits (i.e. 0 to 9) only. Since they
occurred more often it was helpful to reduce there size.
This also help separate the numbers from other characters.
Table IV. sample of the 2003 alphabet
symbol meaning
the number 1
the number 5
symbol "+"
symbol "="
This time five new candidate stars were selected
using the same kind of criteria as for the 1999 message.
The message was repeated three time as well.
Table V. list of target stars for the 2003 message
name Spectral
Hip 26335 (Orion) K7 37.1
Hip 45587 (55 Cnc) G8V 40.9
Hip 4872 (Cassiopeia) K5V 32.8
Hip 52721 (47 UMa) G0V 45.9
Hip 7918 (Andromedae) G2V 41.2
It is now known that some of the target stars
have one or many planets. Like 55 Cnc which is
likely to be a solar system with five planets.
Active SETI is quite new type of activity. Even is
the probability of success is quite low, it raises serious
ethical questions, which are not yet solved. But the
broadcasting technology is well known and relatively
accessible to any one with enough financial resource (as
prove by recent commercial endeavours).
This work has been presented for the first time at
the 1999 American Astronomical Society Meeting. Since
then, the authors of the messages have participated to a
few conferences and published a few papers. The whole
project is done during our spare time. Since we do not
have any funding, participation to conferences is quite
After writing and sending two messages, the
next logical step is to try to understand a possible answer
or even a completely different message.
Our current projects include the development of
a cryptanalytic tool for SETI (i.e. the Young project, in
honnour of Thomas Young) and trying to extend our own
message. The authors start working on coding more
abstract concepts such as equity, democracy and
socialphysics but the work is still going on.
1. C.E. Shannon, A mathematical theory of
communication, Bell System Tech. J., 27, pp 623-656
2. S. Shostak, 1995, SETI at Wider Bandwidths?,
in Progress in the search for Extraterrestrial life, ASP
conf, 74, p447., G. Seth Shostak ed. (1995)
3. F. Drake, Sky & Telescope, 19, pp 140-142
4. F. Drake, G. Helou, The Optimum
Frequencies for Interstellar Communications as
Influenced by Minimum Bandwidth, NAIC 76, Cornell
University, New York (1978)
5. N.T. Petrovich, A SETI Correspondent Helps us
to Discover their Signals, Lost in the Noise of our
Receivers, Ap&SS, 252, 59-66 (1997)
6. Y. Dutil, S. Dumas, Error Correction Scheme in
Active SETI, IAA-01-IAA.9.1.09
7. W.T. Sullivan and K.J. Mighell, A Milky Way
search strategy for extraterrestrial intelligence, Icarus,
vol.60, p.675 (1984)
8. P. Horowitz and C. Sagan, Five years of project
META : An all-sky narrow-band radio search for
extraterrestrial signals, ApJ, 415, p218 (1993)
9. J.M. Cordes, T.J.W. Lazio and C. Sagan,
Scintillations-induced intermittency in SETI, ApJ 487, p.
782, (1997).
10. H. Freudenthal, Lincos design of a language for
cosmic intercourse, North-Holland Publishing Company,
Amsterdam, (1960)
... For example, protons have 1836 times the mass of electrons, regardless of what idiosyncratic measurements are employed. Therefore, the number 1836 can be used to convey that the objects referred to are these particles [5]. Once math has been fully explicated, along with as much physics as might be conveyed thereby, a bridge to chemistry might be devised. ...
Full-text available
For more than 60 years, the predominant SETI search paradigm has entailed the observation of stars in an effort to detect alien electromagnetic signals that deliberately target Earth. However, this strategy is fraught with challenges when examined from ETs perspective. Astronomical, physiological, psychological, and intellectual problems are enumerated. Consequently, ET is likely to attempt a different strategy in order to best establish communications. It will send physical AI robotic probes that would be linked together by a vast interstellar network of communications nodes. This strategy would solve most or all problems associated with interstellar signaling.
The tentatively recognised AnthropoceneAnthropocene epoch illustrates the growing exigent impacts of modern human interactions across multitudes of ecological services. However, this age also draws into sharp focus the entwined cognitive and spatiotemporal dimensions of various active legacies which locally impact our world, yet have now come to also distantly represent human behavioural patterns within phenomena beyond our biome. These remote legacies include the unfolding futurescape of anthropogenic technosignatures, but also the advent of deliberate ‘messages’ using aerospace technologies that varyingly re-present human pantomimes beyond this terrestrial stage. The bulk of these disconnected messaging legacies are extensively dispersed across our spatiotemporal environments. However, there are occurrences of ‘layering’ across select regions—especially within interstellar transmission ventures that intermittently re-target particular stellar systems. These sequences of electromagnetic message-signals arguably remain as the furthest recurring traces of purposeful human agency and representational material practices, but they also reshape the mindscapes of described societies at home. The symbolic relationships encoded within our message-signals, as argued herein, will likely remain equivocal for foreign recipients. However, by taking a closer look at the meta-semiotic features of encountering multiple messages directed towards some targets, what insights can we ourselves glean about our transmission behaviours and expanding worldviews?
Full-text available
By opposition to passive SETI, which want to detect extra-terrestrial civilizations, the goal of active SETI is to establish a communication link with those civilizations. Already difficult, this task is complicated by the lack of knowledge about the nearest civilization. In addition, technical and astrophysical considerations severely limit the communication bandwidth for radio waves. The construction of a message, which can be decoded by an extraterrestrial civilization as been described in details by the Dutch mathematician Hans Freudenthal. Based on these general principles, Frank Drake created a signal, which was sent from Arecibo. However, it appears now that additional steps are needed in a careful design to facilitate its decoding.
It could be that SETI signals have arrived at the Earth, but are lower than the noise level, and our receivers cannot detect them. We analyze the situation when a SETI correspondent sends signals that can be accumulated upon reception, permitting detection of even very weak signals. It is shown that using this method, we can already transmit SETI signals over our entire Galaxy.
We assume that the density of sites of technical civilizations emitting suitable signals whether purposeful or unintentional is proportional to the stellar density at any location in our Galaxy, as modelled by Bahcall and Soneira 1980. A wide variety of possible radio luminosity functions Ø(L) for these civilizations is then assumed and for each the number of detectable signals per square degree over the sky is calculated. We find that most detectable signals occur at galactic latitudes of 10° or less and longitudes within 90° of the galactic center, a region which covers only 9 per cent of the entire sky. This result holds for a wide range of Ø(L) types, including Gaussian distributions and power law functions with slopes less than 2.5, or any combination of these. The Milky Way is much less preferred, but still advantageous, for cases of steep power law functions (slopes greater than 2.5) or Gaussian functions with mean luminosities so low that any existing civilizations can only be detected at distances less than 0.5 kpc. The only cases where low galactic latitudes are not advantageous are (1) for frequencies of operation less than 600 MHz where the deleterious effects on signal-to-noise ratios of the natural galactic background emission become dominant, and (2) in searches for narrowband (≤ 1 Hz) signals at frequencies less than 2 GHz where significant interstellar broadening of signals occurs over distances of ≳10 kpc. Furthermore, all of the above results have broader applicability: they are equally valid for searches for any type of natural radio phenomenon if its probability of occurrence is proportional to stellar density.
An abstract is not available.
We have conducted a five-year search of the northern sky (delta between 30 and 60 deg) for narrow-band radio signals near the 1420 MHz line of neutral hydrogen, and its second harmonic, using an 8.4 x 10 exp 6 channel Fourier spectrometer of 0.05 Hz resolution and 400 kHz instantaneous bandwidth. The observing frequency was corrected both for motions with respect to three astronomical inertial frames, and for the effect of Earth's rotation, which provides a characteristic changing Doppler signature for narrow-band signals of extraterrestrial origin. Among the 6 x 10 exp 13 spectral channels searched, we have found 37 candidate events exceeding the average detection threshold of 1.7 x 10 exp -23 W/sq m, none of which was detected upon reobservation. The strongest of these appear to be dominated by rare processor errors. However, the strongest signals that survive culling for terrestrial interference lie in or near the Galactic plane. We describe the search and candidate events, and set limits on the prevalence of supercivilizations transmitting Doppler-precompensated beacons at H I or its second harmonic. We conclude with recommendations for future searches, based upon these findings, and a description of our next-generation search system.
We consider interstellar scintillations as a cause of intermittency in radio signals from extraterrestrial intelligence (ETI). We demonstrate that scintillations are very likely to allow initial detections of narrowband signals from distant sources (> 100 pc), while making redetections improbable. We consider three models in order to assess the non-repeating, narrowband events found in recent SETI and to analyze large surveys in general: (I) Radiometer noise; (II) A population of constant Galactic sources undergoing interstellar scintillation,; and (III) Real, transient signals (or hardware errors) of either terrestrial or ET origin. We apply likelihood and Bayesian tests of the models to The Planetary Society/Harvard META data. We find that Models II and III are both highly preferred to Model I, but that Models II and III are about equally likely. Ruling out Model II in favor of Model III requires many more reobservations than were conducted in META *or* the reobservation threshold must be much lower than was used in META. *We cannot rule out the possibility that META events are real, intrinsically steady ETI signals.* We recommend that future surveys use thresholds far below the typical false-alarm threshold to lessen the effects of intermittency. The threshold level is best defined in terms of the recording and computational technology that is available at a cost commensurate with other survey costs.
The Optimum Frequencies for Interstellar Communications as Influenced by Minimum Bandwidth
  • F Drake
  • G Helou
F. Drake, G. Helou, The Optimum Frequencies for Interstellar Communications as Influenced by Minimum Bandwidth, NAIC 76, Cornell University, New York (1978)