Timeline for Why do deep space probes have to be sterilized?
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| Aug 8, 2015 at 23:21 | comment | added | Andrew is gone | @DrZ214 The "pause" concept that keshlam mentions is key here. Note that the studies were on bacterial spores - these are effectively dormant 'seeds' which will only become 'alive' again when in favourable conditions. (That sentence is mostly wrong, but it gets the idea across). You might also be interested to read about cryptobiosis (en.wikipedia.org/wiki/Cryptobiosis), the ability of organisms to basically shut down in order to survive abysmally bad conditions - it's more common than you might think. (Moss has been scraped out of Antarctic permafrost & regrown after 1600 years!) | |
| Aug 8, 2015 at 3:54 | comment | added | keshlam | A sufficiently simple organism can sometimes survive things a more complex organism can't. Some small creatures can essentially put life on "pause", drastically slowing or stopping chemical reactions, recovering when water at reasonable temperatures becomes available. Small groups of cells, or small animals, may survive being quick-frozen to liquid-nitrogen temperatures and re-thawed; that's done on a regular basis in seed banks and fertility clinics, and I've seen it done with a goldfish. One more:, viruses when not in a cell are essentially just encapsulated RNA, needing nothing. | |
| Aug 8, 2015 at 3:18 | comment | added | jvriesem | @DrZ214: I'm not a biologist either, but I've spent enough time around people who study this kind of stuff. Two thoughts: 1) consider how seeds can survive after decades and even millennia without nutrients; and 2) scientists are discovering that there are a ton of microorganisms called "extremophiles" that can survive really really inhospitable environments (high heat, high acidity/alkalinity, high pressures, no light, little/no nutrients, etc.). Some space debris could have inner hollow spots—pockets that could have air or moisture. | |
| Aug 7, 2015 at 23:58 | comment | added | DrZ214 | I am not a biologist so this is hard to understand. How can those little guys go so long without food, water, and air! What else is there to live on? Do they eat each other? Maybe with a multi-million cell colony, cannabilization can last a long time? | |
| Aug 7, 2015 at 23:24 | review | First posts | |||
| Aug 7, 2015 at 23:31 | |||||
| Aug 7, 2015 at 23:22 | history | answered | Andrew is gone | CC BY-SA 3.0 |