Except for mild abridgment in the first and last paragraphs, this is pretty much the same essay as "Space Flight and the Spirit of Man", first published in 1961 and later reprinted in Voices from the Sky (1965).
| Date | Publication | Publisher | Type | Page | |
|---|---|---|---|---|---|
| 1999 |
|
Greetings, Carbon-Based Bipeds!: A Vision of the 20th Century As It Happened | Voyager | Nonfiction | 226 |
| August 1999 |
|
Greetings, Carbon-Based Bipeds!: Collected Essays 1934-1998 | St. Martin's Press | Nonfiction | 226 |