PETUNIAS AT THE EDGE OF SPACE: The students of Earth to Sky Calculus have recovered the petunias they sent to the stratosphere last Friday. The flowers left Earth July 19th onboard a helium research balloon, ascended to 110,570 feet, then parachuted back to Earth on the same day. These four screenshots, culled from more than 2 hours of high-definition video, summarizes what happened:
(1) The flowers were pink and alert when they left Earth. (2) An hour later, in the stratosphere, the flowers appear limp and wilted, but they were not. Actually, the flowers were frozen. The petals were bent downward by onrushing wind during the ascent, and they froze in place as the petunias passed through the tropopause where the temperature was -63 C. (3) You can see that the flowers were frozen stiff because when the balloon exploded, they did not move at all. (4) Finally, as the payload parachuted back to Earth the flowers thawed and turned deep purple.
The petunias were just one of several experiments flown to the stratosphere on July 19th during Cassini’s historic photo-shoot of Earth through the rings of Saturn. Other items on board were selected competitively from more than 1056 entries suggested by Spaceweather.com readers.