The Geekian Chronicles

Hey! Wow! We've found water on Mars!

Um, wait, haven't we known that for some time?

Well, yes - for one thing, it's been known for some time that the Martian polar ice caps are water ice (a lot of it) and there's ample evidence that at some point in the past Mars was much warmer and wetter than it is now (the Mars rovers showed that) and there very likely were large seas. More recently, upon examination some features of the planet's landscape can best be explained by flows of water in the "recent" past - "recent" in quotes because what was meant was geologically recent, which could be 100,000 years ago or more. (Hey, when you're used to talking in terms of tens of millions or even billions of years, 100,000 years just ain't that long.)

So what's so cool about this latest news? Because a)we're not talking about ice, we're talking about liquid water and b)we're not talking about 100,000 years ago, we're talking about now. We're talking about seasonal flows of liquid water on Mars, now.

To be more precise, not exactly water but salty mud. The atmospheric pressure on Mars is so low that any water that actually was free on the surface would boil away to vapor vary quickly, so this is likely water mixed with soil - that is, mud. And it's likely salty because the freezing point of salty water is below that of fresh water and Mars is so cold that the difference matters.

Scientists, of course, are not claiming this is absolute, rock-solid proof - only that present-day seasonal flows of salty mud are the best explanation anyone has come up with of the observations. But that doesn't change two facts: One, this is about the strongest evidence to date that liquid water is to be found on present-day Mars and two, that first fact increases the chances that there may be something alive there. It would be unlikely in the extreme to be anything more than microbes - but it would be life on another planet.

And that is just damn cool.

I love science.