Timeline of spaceflight experiments. Four days before Shuttle launch (L-4): Media were loaded into FPAs. L-3: Inocula were loaded. L-2: After checking for contamination, 9% (w/v) paraformaldehyde fixative was loaded for FCM samples only. Samples were stored at ambient temperature (AT) from L-4 to L-1. L-1: After a final contamination check, samples were loaded into the CGBA and stored at 8°C. F0: Space Shuttle Atlantis launched. F8: Samples were activated by mixing the media with the inocula. The temperature in the CGBA was increased to 37°C. F11: Samples were terminated by the addition of fixative (FCM samples only) 72 h after activation. The temperature in the CGBA was reduced to 8°C. F13: Space Shuttle Atlantis landed. Ground controls were conducted at Kennedy Space Center in parallel with spaceflight samples.