Forty-five years ago today — December 14, 1966 — a Delta rocket launched from Cape Canaveral carrying a set of biological specimens to study how microgravity affected them.
(Biosatellite-1 launch. NASA image from Wikimedia Commons.)
Biosatellite-1 made it to orbit successfully. The overall mission failed, however, because the capsule could not be de-orbited. Its retro rocket malfunctioned, leaving the spacecraft in orbit; its orbit eventually decayed in February 1967, but that was long after the experiment’s usefulness would have passed.
Nevertheless, this NASA page about the program notes that Biosatellite-1 “provided technical confidence in the program because of excellent performance in most other areas.” The next biosatellite launch was a complete success.
One might wonder why experiments like these would be carried out, since human beings had been launched into space for years. Didn’t we already know how the space environment affected biological organisms? To an extent, yes, but as I understand it sending up small-scale, short-lived species and studying the effects on them would allow scientists to extrapolate to longer-term effects on larger organisms — like people on long-duration spaceflights.
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