Thursday, July 10, 2008

Phoenix Updates

[Note: I wrote this a week ago, and for some reason didn't post it. Well, have fun!]

Ok, so, I left off Phoenix at landing. Since then, it's done some more pretty cool stuff, and also run into a couple of problems. But don't worry, they're nothing those guys at JPL haven't been able to handle.

So, while taking a cornucopia of photos, the Phoenix team decided to practice scooping and dumping. That way, they became familiar with the soil and figured that they wouldn't screw up when they tried to actually perform experiments on the soil. It turned out that they weren't as familiar with the soil as they thought. It turned out that they'd sorta be wrong. When they actually tried to put the soil in the Thermal and Evolved-Gas Analyzer (TEGA, which basically bakes the soil and analyzes the gases that are emitted), they encountered a little problem. As you can probably see to the right, the soil seems rather clumpy. And over TEGA is a sort of sieve to keep large particles out. Well, it turned out that the clumps turned out to be larger than the holes, and none of the soil could get through.
After much shaking, enough soil finally got into the analyzer so that it could heat up the sample. The result: Not much water. But, that could be expected because the sample was sitting out in the sun for a few days while the lander was trying to shake it in. At the initial heating, no water was given off. However, when they upped the temperature, really heating the soil, they detected some water, which was probably chemically bound to the minerals in the soil itself. So that's still significant, and hints that there was most likely water in the past.

After the analysis, there was a minor glitch on the lander which caused the loss of some nonsignificant science data. That was promptly fixed by the JPL team, so I'll go on to more science.

After scooping the sample for the TEGA experiment, scientists noticed a distinctive white layer in the hole left behind. Two things immediately jumped into mind: salt or ice. There would be an easy way to distinguish between the two: to wait. If after a few days, the layer is different, that indicates that the ice sublimated (changed directly from a solid to a gas). If it doesn't change, then it's probably salt. Well, after a period of anticipation, as you can see in the animation to the left, there was definitely some change, so it's probably ice! And on Mars, there are two kinds of ice, water ice and carbon dioxide ice. However, Phoenix is currently in the middle of Martian summer, so all of the carbon dioxide ice should have sublimated already (it sublimates at a lower temperature). So that leaves: water ice! That is incredible because the ice is far higher than we thought in the Martian soil. This is incredibly encouraging for the possible habitability on Mars.

Of course, Phoenix didn't stop there. There's still another main instrument to be used: the wet chemistry lab. This lab essentially dissolves the soil in some liquid water stored on board and checks how the minerals in the soil behave when dissolved. Well, it turns out that the instruments detected several familiar compounds like potassium, magnesium, and chloride. What's so exciting about those? Those minerals are found on Earth soil! So, the Martian soil is roughly similar to terrestrial soil. This will also be an important find for potential future human habitation because a colonist "might be able to grow asparagus pretty well". Instead of worrying about the soil, we could tackle other problems such as protecting plants from radiation, adapting them to the cold temperatures, and other potential Martian crop failures.

So far, all of this has been extremely exciting. I can't wait to see what other amazing things Phoenix will discover next. You can also follow along. The Phoenix Mars team has a twitter that you can follow: @MarsPhoenix . And of course, you can be friends with the Lander on Facebook. That's a good way to catch up on updates. And I'd like to say, I've been deferring this post for a couple of days now, and every day that went by meant another topic to write about. So, we are getting a TON of info from Mars. In fact, if you want to keep afloat on all the images coming from the lander, JPL is where you can get them first! There's just so much cool stuff coming from that lander!

2 comments:

Larry said...

I don't think you have to patronize your readers like that; I think most of them know what sublimate means.

Vicken said...

Very interesting stuff. . .
and i had no idea before what sublimate meant.