I was seeing tease lines in the news over the weekend and on the NASA twitter feed hinting at a major announcement which would come out today. That spurred the usual rounds of speculation with the most popular candidate being that they turned up some form of life or perhaps a fossil or something along those lines. (Personally I was pitching for a large black obelisk of some sort full of stars, but you can only ask for so much.) I honestly wasn’t getting my hopes up too far because they’ve played these games before. Rather than just announcing what they’ve got they schedule a briefing some days in advance to try to stoke up excitement and get as much press mileage as they can and then it turns out to be something that never lives up to the billing.
This one, while promising in some areas, didn’t prove to be much different. They think they’ve spotted signs of liquid water on the surface of the red planet.
Liquid water runs down canyons and crater walls over the summer months on Mars, according to researchers who say the discovery raises the chances of being home to some form of life.
The trickles leave long, dark stains on the Martian terrain that can reach hundreds of metres downhill in the warmer months, before they dry up in the autumn as surface temperatures drop.
Images taken from the Mars orbit show cliffs, and the steep walls of valleys and craters, streaked with summertime flows that in the most active spots combine to form intricate fan-like patterns.
It’s not that the presence of water on Mars isn’t a big deal in scientific terms… it definitely is. But they already knew there was water there. There are ice caps at the poles and there has been a general consensus for a while now that there was probably at least some water trapped under the surface. The fact that it manages to occasionally run in liquid form on the surface in the low temperatures and pressures is interesting from a physics geek perspective, but it’s really not all that huge in terms of news.
So what does it all mean? Our friend Andrew Malcolm has some thoughts and the background of the research at IBD.
Scientists, being scientists, are most intrigued by what they don’t know. Slowly, thanks to Mars rovers and more sophisticated instrumentation circling above that can penetrate the surface, they are seeking to piece together an ancient history that could presage Earth’s future.
Evidence indicates the past presence of at least one vast Atlantic-size ocean, possibly a billion or more years ago. But where did all that water go? And why? If water is flowing intermittently on Mars now, where does it come from? If it flows in that cold, it must be salt water. Soil salts absorbing moisture from the atmosphere? Soil salts drawing up subterranean water?
One concern this is raising for NASA is how to check out the areas with liquid water (presumably the best shot at finding life) without risking contaminating them with life from Earth. Personally I think that ship may have already sailed. We recently found plankton living on the outside of the space station so we’ve pretty much proven that extremophiles can live pretty much anywhere and can even survive for extended periods in the freezing vacuum and radiation of space. We do try to sterilize everything we launch, but are we that effective at the microbial level? I bet there’s already some Earth based microbes hanging out on Mars thanks to us.
What I’d really like to see is some bacteria that’s actually Martian and figure out a way to bring it back and study it. If it has the same basic type of DNA as all the sub-microscopic critters on the Earth that might really tell us something about the solar system and the universe. (And before you ask, yes… bacteria have DNA. It’s just really simple and located in the nucleoid in the bacterial chromosome.) More to the point, if it’s completely different than any life on Earth, then it arose independently. That might really change our outlook on the world, eh?