Water! On Mars! Again! BIG Deal, or Big DEAL?

Much excitement yesterday around teatime UK time as, around the world, space enthusiasts, scientists and the simply curious – many of them still pale and watery-eyed from sleep deprivation after a late night of lunar eclipse-watching – gathered around their computers or stared into the screens of their tablets and phones to hear NASA make its Big Announcement. “Mars Mystery Solved!” had been the cry a couple of days earlier, prompting outrageous speculation on Twitter, Facebook and every other social media platform (and in Ye Olde printed media too): what were they going to tell us?

Many people were convinced it was a big astrobiology story – that NASA was finally going to announce that Mars wasn’t dead. But what were they going to say? That they’d found fossils? That they had found chemical traces of life? That they had looked again at the Viking laboratory results and decided that maybe the 1970s probe had detected signs of life after all? Others thought it might be an announcement that they had found one of the many space-probes lost on Mars. Others, wearing neatly-folded tin foil hats, were convinced NASA was going to “come clean” and admit that its photos really DID show yetis, small women or dinosaur skulls…

But those who took a little bit of time to think about it, and to do some research, already had a pretty good idea what the announcement was going to relate to. A quick look at the names of the people on the panel was enough to tell one that it was about water, or water processes, rather than life. And digging into the recent work of people on the panel strongly suggested that the news was related to the “gullies” and “dark stains” observed on Mars in recent years.

And that turned out to be the case. No yetis, no tiny women, no fossils – but something very exciting for people with a more scientific approach. Basically, NASA has now got evidence that the dark streaks seen on the sloping sides of certain martian landscape features were caused by water –

WHAT???? Cue disappointed groans from thousands… Oh, great… NASA had found water on Mars. AGAIN.

Hang on, hang on…! Well, ok, it might have sounded like NASA was reheating old news, but to be fair that wasn’t the case. This was different. The water found on Mars so far before has all been frozen or misty water. Orbiters have photographed veritable martian ice rinks, in craters and at the pole, and going all the way back to the Viking days landers have seen frost (frozen water) sparkling on rocks around them before dawn broke. The Phoenix lander (which many people seem to have forgotten about, you hardly hear it mentioned now, do you?) even sent back photographs of a slab of ice right beneath it, and yet more ice glinting on the floors of the trenches it dug in the dirt with its robot arm, and many people think that strange globules photographed on the lander’s own body were actually water droplets. Other missions, notably the Mars Exploration Rovers – now all but erased from history whenever a NASA media event is held, they just aren’t mentioned any more, it’s all about Curiosity – have found evidence of past water flowing or standing on Mars. But this water was, well, proper water. Of a sort.

What NASA was saying was that the dark streaks observed by orbiters had been caused by water. Not, they were quick to point out, liquid water running or rushing down the slopes, not by rivers gurgling down crater or valley walls, not even by weedy trickles slithering their way past and around boulders, creeping towards the floor below. They had been caused more by a dampness gradually spreading through the dirt, staining it, darkening it. So, yes, the dark streaks had been caused by water, but not what we think of as water here on Earth; rather a very salty “brine”, that you couldn’t possibly drink or use for anything, really, spreading like damp through the dirt.

So, to be clear, here’s what NASA HASN’T found…

Seriously, some papers and websites are going well over the top about this news. If NASA had found water running freely on the surface of Mars that would be amazing news, astounding news! What they’ve actually found is evidence for water seeping through the ground, briefly, occasionally, leaving behind, for a brief time, damp dirt. But that’s still exciting, still important, because it’s something new, something found after years of painfully hard, challenging work, at the end of a very rigorous scientific process. And it means that if Mars has water of this type, it improves the chances of finding other, more familiar forms of water elsewhere – and that, in turn, improves the chances of Mars having life, of some sort, today. It also means future astronauts, and after them, settlers and colonists, might have water to use when they get there, instead of having to bring it all with them, or have it sent up from Earth for them.

And that is a Big Deal.

But everyone, please… a deep breath. Calm down. Yes, yaaaaay for the news, yaaaay for the discovery, yaaaaaay for science, and yaaaaay for NASA. But let’s keep it in perspective. Red Mars is STILL Red Mars. It still isn’t the kind of place to raise your kids, and it is still as harsh and cruelly cold as the north pole at midnight on New Year’s Eve. There are no rushing rivers with salmon leaping in the sunlight, no tinkling streams dancing over mossy stones, no rainbow-framed waterfalls roaring. It’s still a dusty, desolate wasteland of a planet that is as dry as a bone compared to Waterworld Earth – but now we know it is damp, in places, now and again. That’s a big discovery, in scientific terms, but no matter what they are saying on TV and in the papers it doesn‘t mean there absolutely definitely is life on Mars.

And it doesn’t mean astronauts will set foot on Mars one day or even one hour sooner than they would have done otherwise, either. There will not be a land-rush to Mars now. Schedules set for future exploration will not change. We won’t see landers dropping down next to these dark streaks and sampling them, and we certainly won’t see astronauts scrambling up those slopes to dig into the dirt and scoop it up in test tubes to analyse “back at the Hab”.

If Mark Watney put THIS type of martian water on his potatoes, THEY WOULD DIE.

Enough frivolity. If you want the hard science behind this story, I can direct you to two very good blogs, each of which goes into the science in much more detail than I could – or at least want to.

Firstly, you should take a look at what blogger “Space Kate” has to say about the story. Kate is very prolific on Twitter, but if you’re not you might not be aware of her great work.  You can change that now by going to…

http://spacekate.com/2015/liquid-water-on-mars-does-it-deserve-the-fuss/

Then – of course – Emily Lakdawalla has the hard science behind the headline. If you want to cut through all the weeds to get to the truth of any space exploration-related story, it’s really quite easy – just go to Emily Lakdawalla’s blog on the Planetary Society website and read her write-up, because the golden rule for whenever a big space/astronomy story breaks is “What has Emily written about it?” She can go into a lot more detail about a story than other people because a) she has all the space she wants on her blog, so doesn’t have to skim over a story and write it in soundbites, b) has a very strong science background, so knows what she’s talking about, and c) is an expert communicator. And she is very honest too; if she thinks NASA is over-hyping a story, or making wild claims or assumptions she’ll say.I admire her and her work a lot.

http://www.planetary.org/blogs/emily-lakdawalla/2015/09281219-nasas-mars-announcement.html

So, after all that hard science, what does this discovery mean for the future? Well, in an ideal world it would mean that NASA sat back in its chair, let out a deep sigh, stared out the window for a few hours and had a good hard think about what it is doing, before deciding to stop “following the water” and studying one rocky landing site after another and, instead, bite the bullet and design and send a mission to Mars dedicated solely to looking for signs of life, past or present. As huge a supporter of NASA as I am, and as thrilling as I personally find images of martian geology, even I have seen enough “rusty red” rocks, enough “melon-sized” boulders, enough “crumbling outcrops” and “fascinating veins” to last me the rest of my lifetime. It’s time NASA went to Mars for the only really good reason TO go to Mars – to look for signs of life. IMHO, of course.

But as optimistic and enthusiastic as I am, I’m not naive or stupid. I know that’s not going to happen. In the real world, this discovery means no new hardware will be built and sent to Mars, and there will be no boot-prints in the dirt – damp or otherwise – for a good couple of decades yet; for now, watching THE MARTIAN is as close as we’re going to get to see humans exploring Mars. What it means is more science is needed, and will be done, and more hard work is needed, and will be done, so scientists can refine these results even further. That takes time, but tough, that’s how science works.

But if you’re up before dawn any time soon, take a look at the eastern sky and you’ll see a line of three stars shining there. These aren’t actually stars, they’re planets. I took this photo the other morning…

The middle one is Mars, see? When I took this photo, Mars was known to be a planet with water, but not actually known to be “wet” anywhere. That has changed, and that is why this announcement was worth making, and why this discovery is important.