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"Broadcast for Extra-Terrestrial Intelligence
from Evpatoria Deep Space Center"
Report on Cosmic Call 1999
Prof. Alexander L. Zaitsev
Institute of Radio Engineering and Electronics Russian Academy of Science
Dr. Sergey P. Ignatov
Institute of Space Device Engineering Russian Space Agency
CONTENTS
1. Introduction
2. Background
3. Methodology
8. Supplement: Cosmic Call Logbook
This Report outlines methodology, hard- and software, which were developed to transmit first public Interstellar messages from Evpatoria Deep Space Center (EDSC), and describes four Cosmic Call Sessions, which were fulfilled in EDSC on May 24 and June 30 - July 1, 1999.
The Encounter 2001 Mission (www.teamencounter.com) consists of two elements: The Cosmic Call and The Millennial Voyage. The first one represents the series of interstellar transmissions to the stars, which have the similar spectral type as Sun and probably, the own planetary system. The selection of this stars is mainly base on the SETI Institute target list (Yvan Dutil, e-mail communication on 5 Jun 99):
TABLE 1. Target Stars
Target Number
1
2
3
4
5
Star Name
HD178428
HD186408
HD190067
HD190360
HD190406
Visual Magnitude
6.08
5.99
7.15
5.73
5.08
Spectral Type
G5V
G2V
G8V
G6IV+
G1V
Light Years
68.3
70.5
63.0
51.8
57.6
RA, J2000
19h07m57.32s
19h41m48.95s
20h02m34.15s
20h03m37.41s
20h04m06.23s
PMRA, arcsec/yr
0.06561
- 0.14775
- 0.18607
0.68332
- 0.39407
LY * PMRA
4.48s
- 10.42s
- 11.72s
35.40s
- 22.70s
RA + LY * PMRA
19h08m01.80s
19h41m38.53s
20h02m22.43s
20h04m12.81s
20h03m43.53s
Dec, J2000
+16d51m12.24s
+50d31m30.21s
+15d35m35.51s
+29d53m48.51s
+17d04m12.64s
PMDec, arcsec/yr
- 0.30446
- 0.15885
- 0.58207
- 0.52406
- 0.40642
LY * PMDec
- 20.79
- 11.20s
- 36.67
- 27.15s
- 23.41
Dec + LY * PMDec
+16d50m51.44s
+50d31m19.01s
+15d34m58.84s
+29d53m21.36s
+17d03m49.23s
The lines [RA + LY * PMRA] and [Dec + LY * PMDec] denote the actual values of Right Ascension (RA) and Declination (Dec), which are accounting the distance LY and proper motion PM, and which were used for computations of elevation and zenith angle of given star during its tracking by Evpatoria antenna.
According with Specification, for Cosmic Call we have used the 70-m fully steerable parabolic antenna and power transmitter, which are usually using for planetary and asteroid radar researches, with the following parameters:
Central Frequency - 5010.024 MHz
Antenna's Diameter - 70 m
Effective Aperture - 2500 m2
Continuous Power - 150 kW
Left Circular Polarization.
Each Cosmic Call consists of two parts. Part I is the selected Earth's knowledge for Extraterrestrial, and Part II contains the names and personal messages of Encounter 2001 participants. Regarding Part I, we have a total of 4 messages, to include in it:
1. Dutil Message,
2. Braastad Message,
3. Arecibo Message, and
4. Encounter 2001 Staff Message.
For explanation of message's content please visit www.teamencounter.com. Each above messages are the binary ["0" & "1"] streams of information, separated to each other by 5 second pauses. As a result, we have the ternary situation: ["0", "1", and "pause"], so need to use the ternary modulation to transmit the Cosmic Call. We have used the frequency modulation for this purpose, as more suitable for reliability of power klystron transmitter and for more antijamming, than amplitude one.
The EDSC hardware was upgraded to introduce the frequency modulation mode. The coherent frequency synthesizer Ch 6-36, controlled by personal computer via custom-built interface, was used. Also, the special device to exercise of power klystrons, was developed.
The software for gathering all messages and creating the Cosmic Call stream, was written on C language. Here is the screen's view of control personal computer monitor during "on-line" generation of Cosmic Call stream:
Start of Session |
|
↓ |
|
Dutil Message |
(Thrice-repeated program cycle) |
Braastad Message |
|
Arecibo Message |
|
Encounter 2001 Staff Message |
|
↓ |
|
Part II |
|
↓ |
|
End of Session |
The Part I was transmitted three times at a rate 100 bits per second, and the Part II - only once at a rate 2000 bits per second.
The first Cosmic Call was transmitted on May 24, 1999, to the target number 2 - star HD 186408. Three other transmissions were made during the night June 30 - July 1. Table 2 contains an information about all four Cosmic Call Sessions.
TABLE 2. Cosmic Call Sessions
Session
1
2
3
4
Target Star
HD 186408
HD 178428
HD 190406
HD 190360
Date
24 May 1999
30 June 1999
30 June - 1 July
1 July 1999
UT of Start
16:20:00
16:45:00
21:10:00
01:22:00
Transmitted Power, kW
148
152
152
152
UT of Finish
20:15:03
20:40:15
01:05:02
05:17:01
Transmission Rates: 100 Hz for Part I and 2000 Hz for Part II. Frequency Deviation: +/- 24 kHz ("pause" = 5010024 kHz, "0"= 5010000 kHz, "1" = 5010048 kHz), both for Part I and II.
The most difficult problem, which occurs during long (few hours) transmission is a short life of power klystrons. At present we have only one reserve klystron, unfortunately, so plan to develop special device to regenerate the cathodes of defect klystrons. Also, hard- and software are needed in some modifications in order to increase theirs flexibility and reliability before next Cosmic Calls.