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Report on Cosmic Call 1999

"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

4. Hardware Upgrade

5. Software Upgrade

6. Cosmic Call Sessions

7. Future Prospects

8. Supplement: Cosmic Call Logbook

 

Introduction

 

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.

 

Background

 

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.

 

 

Methodology

 

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.

 

Hardware Upgrade

 

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.

 

Software Upgrade

 

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.

 

Cosmic Call Sessions

 

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.

 

Future Prospects

 

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.