Survival in Extremophile conditions- Balloon Launches
Working at NASA Ames, we had the good fortune of meeting Jack Cackler, who was trying to prototype small balloon launches to the stratosphere. Located at 10 to 50 kilometers above the ground, the stratosphere has conditions that are out of this world: a temperature range of -56 to -3°C (it actually increases as you ascend), and atmosphere 0.001 percent of that of earth’s sea level. To take advantage of this rare opportunity, we prepared two dried samples of S. pasteurii to be sent up in the balloon, to test the ability of the bacteria to withstand the extremes in temperature, depressurization and radiation bombardment. Note that the microbes we flew were not genetically altered, and all practice was done under proper FAA notification.
Thorough Protocols for the preparation can be found here
Our first balloon went up to 80,000 ft (24 kilometers), from which the curvature of the earth was visible.
Unfortunately, our S. pasteurii cargo, as well as other biological samples, cargo, did not survive the first flight. The biocemented brick that accompanied the samples up suffered some mechanical damage, and a qualitative change in brittleness. It is suggested that the this structural change was influenced by the temperature change, and corresponding thermal contraction/expansion. Further experimentation will have to be done to isolate the cause of the structural change and investigate its implications for space applications.
Our second balloon went up to 110,000 ft (33.5 kilometers), where the atmospheric pressure was slightly below that of Mars.
During our second flight (accompanied by the BBC ), we prepared the S. pasteurii inside Whirlpak bags. Surprisingly enough, upon retrieval, the the samples inside the Whirlpak bags exhibited urease activity! The ones outside the bags did not, though mysteriously enough both samples grew back on Bang media plates in seemingly equal quantities. Further experimentation must be done to ascertain the exact nature of the survival.
Our original grand plan was to have one final balloon flight, after our transformation of S. pasteurii with Newcastle 2009’s sporulation regulation gene, to see if induced sporulation could have increase the percentage of survivors. Unfortunately, difficulties in transforming S. pasteurii put this this plan on hold.