Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization

First Edition

© 1975-1979, 2008 Robert A. Freitas Jr. All Rights Reserved.

Robert A. Freitas Jr., Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization, First Edition, Xenology Research Institute, Sacramento, CA, 1979; http://www.xenology.info/Xeno.htm


24.3  Extraterrestrial Starprobes and Artifacts

Surprisingly enough, the Arecibo radio pictogram was not mankind’s first intentional space message for ETs. Pioneer 10, a spacecraft, was first.

Pioneer 10 was launched toward Jupiter on 3 March 1972, loaded with scientific equipment designed to measure the radiation environment surrounding the giant planet. Traveling at 11,000 meter/second, the interplanetary probe encountered Jupiter on 4 December 1973 and swung around its massive bulk at close range. Assisted by a kind of "slingshot effect," the spacecraft rapidly accelerated up to 23,000 meter/second. In 1976 it reached the orbit of Saturn, and three years later the orbit of Uranus, where its radio signals finally became too weak for detection from Earth. In 1983 Pioneer 10 will cross the orbit of Pluto and head out into deep space at an interstellar cruising speed of 0.0043%c (13,000 meter/second).3136 It will become the first manmade object to leave the solar system, our first interstellar spacecraft.*

Attached to the exterior of the vehicle is a 6" x 9" gold-anodized aluminum plate engraved as shown in Figure 24.10. The message announces our existence to the cosmos. Any alien species which picks it up and deciphers its meaning can tell who built it, when and where it was built, how tall we are, our basic physiology, and our approximate technology at the time of launch.168


Figure 24.10 Messages from Interstellar Probes: The Pioneer 10 Plaque

Below is a drawing of the engraved gold-anodized aluminum plate which is now hurtling out into inter stellar space at about 0.0043%c, in the general direction of Aldebaran in the constellation Taurus.

The message begins at the top with a schematic representation of the "hyperfine transition" of neutral atomic hydrogen: In going from a state in which the spin of the electron and proton are aligned, to a state in which they are opposed, radio waves at 1.42 GHz are emitted. Since hydrogen is the most abundant element in the universe, and the "hyperfine transition" the most common change of state for hydrogen, it is expected that alien radioastronomers will early detect this radiation and thus understand the significance of the symbols engraved on the plaque. Since a frequency of 1.42 GHz is a wavelength of 21 centimeters, this is adopted as the unit of length by the binary digit designation "1" under the line connecting the hydrogen atom symbol. At the extreme right are depictions of human beings. Next to them are tote marks indicating the binary number eight. Eight times 21 centimeters is 1.68 meters, the average human height. The outline of the Pioneer craft behind them confirms this estimate. Where does the Pioneer craft come from, and when was it launched Curious ETs can answer these questions by carefully examining the plaque. At left of center is some object centered among 15 other objects. Each is labeled with a very long string of binary digits; the only thing that can be known to this accuracy is the period of a pulsar. Since pulsars slow down at known rates, scientists estimate that even 106-108 years after launch, the launch date of Pioneer can be pinpointed by ETs to the nearest century or millennium. The solid line to each pulsar represents its relative distance from Pioneer’s launch point. Using computer analysis, our solar system may be located to within 60 light-years from anywhere in our Galaxy. Our position is specified to 1 of 1000 possible Stars.

As a final aid in locating Sol, the Solar System is sketched along the bottom of the plaque. The path of the Pioneer spacecraft is also shown, emanating from the third planet, then whipping past the fifth and on out into inter stellar space. The distance of each world from the sun is given in binary digits. Finally, the radio dish points back at the third planet as it makes its exit from the system. Clearly, the intelligent beings are there.


A vastly more sophisticated message was affixed to each of the follow-up missions to the jovian worlds in the late 1970’s, called Voyagers 1 and 2.3131 Instead of a simple plaque, a phonograph record was the chosen medium. The Voyager phonograph record contents are too lengthy to reproduce here but are listed in Table 24.4.


Table 24.4 Complete Texts of the Voyager 1 and Voyager 2 Phonograph Records



Pictures (in electronic form).
President Carter's message (in electronic form).

U.N. Secretary General Waldheim's message ( spoken ).

Greetings in 60 languages. 

Sounds at Earth.


37 Family portrait, Nina Leen.
38. Diagram of continental drift. Jon Lomberg.

39. Structure of Earth, Jon Lomberg.

40. Heron Island (Great Barrier Reef of Australia), Dr Jay M. Pasachoff.

41. Seashore, Dick Smith.

42. Snake River and Grand Tetons, Ansel Adams.

43. Sand dunes, George Mobley.

44. Monument valley.

45. Forest scene with mushrooms, Bruce Dale.

46. Leaf, Arthur Herrick. 

47. Fallen leaves, Jodi Cobb. 

48. Sequoia, Josef Muench.

48. Snowflake, R. Sisson

49. Tree with daffodils, Gardens of Winterthur.

50. Flying insect with flowers, Borne On The Wind.

51. Diagram of vertebrate evolution, Jon Lomberg.

52. Seashell (Xaneidae).

53. Dolphins, Thomas Nebbia.

54. School of fish, David Doubilet.

55. Tree toad, Dave Wickstrom.

56. Crocodile, Peter Beard.

57. Eagle. Donona.

58. Waterhold, South African Tourist Corporation 

59. Jane Goodall and chimps, Vanne Morris-Goodall.

60. Sketch of bushmen. Jon Lomberg.

61. Bushmen hunters, R. Farbman.

62. Man from Guatemala, UN.

63. Dancer from Bali, Donna Grossenor.

64. Andean girls. Joseph Scherschel.

65. Thailand craftsman, Dean Conger.

66. Elephant. Peter Kunstadter.

67. Old man with beard and glasses (Turkey). Jonathon Blair.

68. Old man with dog and flowers, Bruce Bnumann. Mountain climber. Gnston Rebuffat.

70. Cathy Rigby. Philip Leonian.

71. Sprinters (Valeri Borzov of the U.S.S.R., in lead), The History of the Olympics.

72. Schoolroom, UN.

73. Children with globe.

74. Cotton harvest, Howell Walker. 

75. Grape picker. David Moore.

76. Supermarket, H. Eckelmann.

77. Underwater scene with diver and fish, Jerry Greenberg.

78. Fishing boat with nets, UN.

79. Cooking fish. Cooking of Spain and Portugal.

80. Chinese dinner party, Michael Rougier.

81. Demonstration of licking, eating and drinking, H. Eckelmann.

82. Great Wall of China. H. Edward Kim.

83. House construction (African), UN. 

84. Construction scene (Amish country), William Albert Allard.

85. House (Africa), UN.

86. House (New England). Robert Sisson.

87. Modern house (Cloudcroft, New Mexico) . Dr. Frank Drake.

88. House interior with artist and fire. Jim Amos.

89. Taj Mahal, David Carroll.

90. English city (Oxford), C. S. Lewis, Images of His World.

91. Boston, Ted Spiegel

92 UN Building Day. UN.

93. UN Building Night. UN.

94. Sydney Opera House, Mike Long.

95. Artisan with drill. Frank Hewlett.

96. Factory interior. Fred Ward.

97. Museum. David Cupp.

98. X-ray of hand. H. Eckelmann.

99. Woman with microscope. UN.

100. Street scene. Asia (Pakistan), UN.

101. Rush hour traffic, India. UN.

102. Modern highway (Ithaca), H. Eckelmann.

103. Golden Gate Bridge. Ansel Adams.

104. Train. Gordon Gahan.

105. Airplane in flight, Dr. Frank Drake.

106. Airport (Toronto), George Hunter.

107. Antarctic Expedition. Great Adventures with the National Geographic.

108. Radio telescope (Westerbork, Netherlands), James Blair.

109. Radio telescope (Arecibo), H. Eckelmann.

110. Page of book (Newton, System of the World).

111. Astronaut in space. NASA.

112. Titan Centaur Launch, NASA.

113. Sunset with birds, David Harvey.

114. Spring Quartet (Quartetto Italiano), Phillips Recordings.

115. Violin with music score (Cavotina).

(In Sequential Order)

1. Bach Brandenburg Concerto Number Two, First Movement. Karl Richter conducting the Munich Bach Orchestra.
2. "Kinds of Flowers" Javanese Court Gamelan, recorded in Java by Robert Brown, Nonesuch Explorer Record.

3. Senegalese Percussion, recorded by Charles Duvelle.

4. Pygmy girls initiation song, recorded by Colon Turnbull (Zaire).

5. Australian Horn and Totem song. Recorded in Australia by Sandra LeBurn Holmes. Barnumbirr-Morning Star Record.

6. "El Cascabel" Lorenzo Barcelata. The Mariachi Mexico.

7. "Johnny B. Goode", Chuck Berry.

8. New Guinea Men's House, recorded by Robert MacLennan.

9, "Depicting the Cranes in Their Nest" recorded by Coro Yamaguchi (Shakubachi).

10. Bach Partita Number Three for violin. Gavotte et Rondeaus, Arthur Gruminux, violin.

11. Mozart Magic Flute, Queen of the Night (Aria Number 14) Edda Moser. soprano.

12. Chakrulo. Georgian (USSR) folk chorus.

13. Peruvian Pan Pipes performed by Jose Maria Arguedas.

14. Melancholy Blues performed by Louis Armstrong, Columbia Records.

15. Azerbaijan Two Flutes. Recorded by Radio Moscow.

18. Stravinsky. Rite of Spring. Conclusion. Igor Stravinsky conducting the Columbia Symphony Orchestra.

17. Bach Prelude and Fugue, Number One in C Major from the Well Tempered Clavier, Book Two. Glenn Gould, piano.

18. Beethoven’s Fifth Symphony, First Movement. Otto Klem Klemperer conducting, Angel Recording.

19. Bulgarian Shepherdess Song. "Izlel Delyo hajdutin." sung by Valya Balkanska.

20, Navajo Indian Night Chant. Recorded by Williard Rhodes.

21. The Fairie Round from Pavans, Galliards, Almalus. Recorded by David Munrow.

22. Melanesian Pan Pipes. From the collection of the Solomon Islands Broad

casting Service.

23. Peruvian Women's Wedding Song. Recorded in Peru by John Cohen.

24. "Flowing Streams" -- Chinese Ch'in uu music. Performed by Kuan P'ing-Hu. 

25. "Jaat Kahan Ho"-- Indian Raga. Performed by Surshri Nt-tan Bai Kerkar.

26. "Dark Was the Night" performed by i Blind Willie Johnson. 

27. Beethoven String Quartet Number 13 "Cavatina", performed by Budapest String Quartet.

(Not In Sequential Order)




































Ila (Zambia)







Amoy (Min dialect)










(In Order of Sequence)

Planets (Music)


Mud Pots



Crickets, Frogs





Wild Dog
Footsteps and Heartbeats



Dogs, domestic

Herding sheep

Blacksmith shop




Morse Code

Horse and Cart
Horse and Carriage

Train Whistle



Auto gears


Lift-off Saturn 5 Rocket



Life signs -- EEG, EKG


    This Voyager spacecraft was constructed by the United States of America. We are a community of 240 million human beings among the more than 4 billion who inhabit the planet Earth. We human beings are still divided into nation states, but these states are rapidly becoming a single global civilization.
    We cast this message into the cosmos. It is likely to survive a billion years unto our future, when our civilization is profoundly altered and the surface of the Earth may be vastly changed. Of the 200 billion stars in five Milky Way galaxy, some -- perhaps many -- may have inhabited planets and spacefaring civilizations. If one such civilization intercepts Voyager and can understand these recorded contents, here is our message:

    "This is a present from a small distant world, a token of our sounds, our science, our images, our music, our thoughts and our feelings. We are attempting to survive our time so we may live into yours. We hope someday, having solved the problems we face, to join a community of galactic civilizations. This record represents our hope and our determination, and our good will in a vast and awesome universe."

Jimmy Carter, 
President of the United States of America.
The White House,
   June 16, 1977.


As the Secretary General of the United Nations, an organization of 147 member states who represent almost all of the human inhabitants of the planet Earth, I send greetings on behalf of the people of our planet. We step out of our solar system into the universe seeking only peace and friendship, to teach if we are called upon, to be taught if we are fortunate. We know full well that our Planet and all its inhabitants are but a small part of the immense universe that surrounds us and it is with humility and hope that we take this step.

Kurt Waldheim



1. Calibration circle, Jon Lomberg.
2. Solar location map, Dr. Frank Drake.

3. Mathematical definitions, Dr. Frank Drake.

4. Physical unit definitions, Dr. Frank Drake.

5. Solar system parameters, Dr. Frank Drake.

6. Solar system parameters, Dr. Frank Drake.

7. The Sun. Hale Observatories.

8. Solar spectrum. H. Ecklemann.

9. Mercury, NASA.

10. Mars, NASA.

11. Jupiter, NASA.

12. Earth. NASA.

13. Egypt. Red Sea, Sinai Peninsula and the Nile, NASA.

14. Chemical definitions, Dr. Frank Drake.

15. DNA Structure, Jon Lomberg.

16. DNA Structure magnified. Jon Lomberg.

17. Cells and cell division, Turtox/Cambosco.

18. Anatomy 1: Field Enterprises Educational Corp. and Row, Peterson & Co.

19. Anatomy 2: Do.

20. Anatomy 3: Do.

21. Anatomy 4: Do.

22. Anatomy 5: Do.

23. Anatomy 6: Do.

24. Anatomy 7: Do.

25. Anatomy 8: Do.

25a. Human sex organs. Life: Cells, Organisms, Populations.

26. Diagram of conception, Jon Lomberg.

27. Conception. Lennart Nilsson.

28. Fertilized ovum, Lennart Nilsson.

29. Fetus diagram, Jon Lomberg.

30. Fetus, Dr. Frank Allan.

31. Diagram of male and female, Jon Lomberg.

32. Birth, Wayne Miller.

33. Nursing mother, UN.

34. Father and daughter (Malasla), David Harvey.

35. Group of children, Ruby Mera.

36. Diagram of family ages. Jon Lomberg.


1 NASA Press Release 77-159, Aug. 1, 1977.


The record is a 12" copper disk to be played at 16 2/3 revolutions/minute using a ceramic cartridge and stylus enclosed for the purpose. Instructions for playback are written in pictorial sign language on the outside of the aluminum can holding the record. Remarks Carl Sagan optimistically: "If they’re able to tool around in interstellar space picking up stray, derelict spacecraft, they ought to be able to figure out our instructions.**


* According to computer projections, Pioneer 10 is creeping out into a relatively empty region of space. Estimates indicate that it should pass fairly close to the star Aldebaran (aTauri), which is 68 light-years from Earth, in the year 1,601,983 A.D.

** Computer projections by Michael B. Helton at JPL show that the Voyagers, like the Pioneers before them, will not closely encounter any alien solar systems. Voyager 1 will pass Pluto’s orbit late in 1987 and head out toward the constellation Ophiuchus (Declination 10.1º, Right Ascension 17h, 20m). Voyager 2, assuming it goes to Uranus but not Neptune, will exit the solar system in mid-1989 on the way to Capricornus (Declination -14.9°, Right Ascension 21h, 1m). In about 40,000 years both craft should coast to within 1.7 light-years (Voyager 1) or 1.1 light-years (Voyager 2) of AC+79 3888, a fourth magnitude star. Voyager 2 should pass a similar distance from another star (AC -24 2833-183) 100,000 years later in Sagittarius, and about 375,000 years after that, Voyager 1 will pass within 1.5 light-years of AM +21 652 in the constellation of Taurus.3207


Last updated on 6 December 2008