Format Manuscripts/Mixed Material
Contributors Sagan, Carl
Dates 1960
Language English
Subjects Carl Sagan
Drake Equation
Drake, Frank D.
Extraterrestrial Life
Habitable Planets
Interplanetary Voyages
Life on Other Planets
Relativity (Physics)
Space Travel
Direct contact among galactic civilizations by relativistic interstellar spaceflight : draft
Contributor Names
Sagan, Carl (Author)
Created / Published
Subject Headings
-  Space travel
-  Interplanetary voyages
-  Extraterrestrial life
-  Life on other planets
-  Habitable planets
-  Drake, Frank D
-  Drake equation
-  Relativity (Physics)
-  Carl Sagan
-  Manuscripts
-  A draft of Sagan's paper, "Direct contact among galactic civilizations by relativistic interstellar spaceflight." The paper explores models for the distribution of technical civilizations in the galaxy. Using Frank D. Drake's equation to suggest that 0.001 percent of stars in the sky have a planet on them on which an advanced civilization resides. Sagan suggests the nearest such advanced civilization is several hundred light years away from earth. From there, Sagan explores the feasibility of interstellar spaceflight as a means for traversing such distances. The paper ends in consideration of the possibility of extraterrestrial contact with Earth in the past. The paper was initially presented at a meeting of the American Rocket Society in November of 1962 and subsequently submitted to Planetary and Space Science in December of 1962 and published in 1963.
Dimensions in inches: 8 1/2 x 5 (1 page)
Source Collection
The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive
Manuscript Division

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