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Seriously, it's a real question on a cosmological scale whether life travels between planets or star systems. We know microbes are ejected inside rocks by asteroid impact, and spores are possibly swept into space from the upper atmosphere. But can they survive a long journey?
2/ Strep bacteria were found on the Surveyor spacecraft camera returned by astronauts from the Moon. They "reactivated" when returned to a wet environment. But researchers now say it was likely just lab contamination AFTER the camera was returned to Earth. space.com/11536-moon-mic…
3/ So the question remains whether bacteria can survive in space for any time: in the hot/cold conditions, the vacuum, the high energy particle radiation, etc. And where can we look for bacteria we put into that environment? In the bags of human excrement at the Apollo sites!
4/ Those bags contain not just feces but also many species of bacteria, viruses, etc. They've been on the Moon almost 50 years. Did any life survive? Will it "reactivate" if we put it into water? The best way to know is to sample the bags and do experiments.
5/ Here is a list of the "8 weirdest things we've left on the Moon" where you can see pictures of the urine and feces bags. They were tossed onto the lunar surface out the hatch of the Lunar Module after the last spacewalk before it returned the crew to Earth, because...
6/ ...you don't want to waste your precious rocket fuel launching poop. You need that fuel to provide extra margin in case something goes wrong. So all the mass that wasn't needed to return to Earth was left on the lunar surface. vox.com/2015/3/8/81632…
7/ An Apollo urine bag is on the left, and a feces bag on the right in this picture. You can see the feces bag is transparent. I wonder how well ultraviolet (UV) penetrates that plastic, since exposure to UV is a crucial parameter for the survival of microbial life in space. 
8/ We would love to get more data on how these materials fared in the space environment: not just how life survived, but all the materials. It will help us learn how to live & work in space. That's why Apollo 12 visited Surveyor 3, which had been on the Moon just 2.5 years.
9/ The Apollo sites have now been there 20 times longer than Surveyor was. (That's more than and order of manitude longer.) So these are the most important sites where we could get these kinds of data. This was my original interest in preserving the sites!
10/ Because to get the data without ruining them, we would need to approach the bags of urine and feces carefully and avoid contaminating or damaging them. It would take great caution. How close can we land? How fast can we drive up? How do we touch them? Etc.
11/ We don't want to botch the experiment because it touches on a central question of cosmological biology: can simple life spread through the cosmos like radio waves, or does it need to wait billions of years until there are technological species with spaceships to spread it?
12/ If simple life can survive 50 years at the Apollo sites, that's 9 orders of magnitude longer than surviving just 1 second. 8 more steps up this logarithmic scale and it could survive the entire age of the universe. Something less that, it could survive journeys between stars.
13/ This is just one of the MANY important scientific questions we will try to answer when we get back to the Moon, including visiting the Apollo sites. So that was my original interest in preserving the sites. Bags of human poop and other stuff. 😅
14/ But the historians, anthropologists, and archeologists have educated me that there is actually far more to it even than this. In meetings about preserving the sites, Beth O'Leary and @Launiusr explained that they are too important to let the physical scientists run amok 😅
15/ And they convinced me. These are the first places humans stepped onto another world! There is a balance between allowing some access for science and the public to experience them, vs keeping them undisturbed for purposes of the future. Developing technology can help...
16/16 We are pretty far along in having tech to build landing pads on the Moon. Landing pads can control the rocket blast effects. This will help not only to protect the Apollo sites, but to alleviate geopolitical conflict over the blasts affecting other nations' outposts.
