The Phoenix lander has been doing all sorts of cool things since it touched down on the red planet a few months ago. And the news keeps coming down in a flurry… literally!
Phoenix has an experiment on board that beams a laser upward to measure how the atmosphere and ground interact. Incredibly, it detected snow falling from clouds! Sadly, the snow vaporized before it could get the surface, so there won’t be any Marvin the Snowman antics from the Phoenix engineers. Actual falling snow has never been detected on mars before, so this is pretty cool. Every time I hear something like that, I’m reminded that Mars is a world, an actual place, and not just a reddish-butterscotch dot in the sky. Wow.
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Also, Phoenix has detected what looks to be calcium carbonate — chalk — in the Martian regolith. On Earth, that only happens when there is interaction with water, so this is another piece of evidence on the checklist that says that liquid water once flowed at least for a while on the surface of Mars. The evidence for calcium carbonate comes from the ovens on board the lander used to bake the regolith: as the samples were heated, carbon dioxide was detected when the temperature reached a point known to be the decomposition temperature of calcium carbonate, which is also known to release CO2 in these conditions.
I should caution conclusion-jumpers that while yes, calcium carbonate can be created on Earth by the death and compression of marine animal shells, there are plenty of non-biological processes that can generate it as well. Heck, calcium carbonate is the principle ingredient of chicken egg shells, but I think claiming that Marvin’s been making omelets is a stretch too.
Anyway, as northern winter on Mars sets in, and the Phoenix mission winds down, I expect the scientists involved will be sad, but still overjoyed to have so much data with which to work. It’ll be very exciting to see what else they can find!
Picture credit: Mars image from NASA/Phoenix, the snowman from Mykl Roventine’s Flickr set (CC license), and the Marvin found randomly on the web with no pedigree. I made the composite, without an Earth-shattering kaboom.









September 29th, 2008 at 2:16 pm
How do you say regolith again?
September 29th, 2008 at 2:20 pm
It’s pronounced “dirt”.
September 29th, 2008 at 2:43 pm
Phil…Marvin had the Illudium Pu-36 Explosive Space Modulator for his omelets. Its no wonder there arent Dino bones sticking out of the ground
cool info about the snow!
September 29th, 2008 at 3:12 pm
Mmmm — Baked regolith. Yum.
September 29th, 2008 at 3:13 pm
I think the calcium carbonate came from duck eggs… http://www.flickr.com/photos/kathyapplebaum/2884737123/
Yeah, I was the only one geeky enough in my photography class to use Mars photos for our Photoshop assignment.
September 29th, 2008 at 3:20 pm
I knew my dance and sacrifice to THE GREAT SNOW GOD would be received well this year. TGSG made it snow on another freaking planet, HE is truly powerful. I’m expecting 1200 inches in Jackson, WY this year!
September 29th, 2008 at 3:21 pm
Wow, I leave to go get the mail and it snows on Mars!
September 29th, 2008 at 3:27 pm
Wow! Snow? That is very cool. Too bad no Martian snowmen, though. That could be fun.
September 29th, 2008 at 3:32 pm
That is so cool. Pun intended.
September 29th, 2008 at 4:11 pm
Wonder if Billy Meier predicted this.
September 29th, 2008 at 4:27 pm
Ummm, not to rain on the parade here, but aren’t eggs, their production, laying and subsequent hatching, kind of a biological process? Need. Better. Example.
September 29th, 2008 at 5:06 pm
‘regolith’ isn’t that name of one of Sarah Palin’s children?
September 29th, 2008 at 5:24 pm
Gonzo. That. Was. Exactly. My. Point.
September 29th, 2008 at 5:38 pm
@Daerek Colanduno
I don’t know but since she is the same solar system as mars does that make her an expert on interplanetary affairs.
September 29th, 2008 at 5:39 pm
sorry suppose to be Derek.
September 29th, 2008 at 5:43 pm
Derek Colanduno: Yup. She’s my Evil Twin. And I’m the Eviller Twin.
September 29th, 2008 at 5:53 pm
You can see an image of the LIDAR measurements of the snow.
September 29th, 2008 at 5:56 pm
awesome news. too bad there’s no pictures of mars snow… i wonder if it would look pink-ish…? or green-ish, like the mars sunsets?
September 29th, 2008 at 5:59 pm
Phil I can’t believe no one has complimented you on your photoshop skillz yet. tsk tsk
September 29th, 2008 at 8:03 pm
I always love the first snow of winter. I just want Phoenix to have enough juice remaining to photograph it’s impending doom, so to speak. Watching the world freeze around it would be fun. I doubt this will happen, but I’ll dream.
September 29th, 2008 at 8:31 pm
@Todd
I’m sure his acolyte in Santa Monica is typing up the prediction as we speak…
September 30th, 2008 at 2:23 am
@Skeptigator: NO astronomer has EVER admitted being able to use Photoshop. That would ruin the whole “We DID land on the moon, honest!” hoax/conspiracy that all astronomers are initiated to right after getting their diploma. See?
September 30th, 2008 at 4:57 am
But Marvin has a floating Sky platform, which was high enough for it to get covered with snow. So he WAS able to make his snow-martian after all!
Isn’t that lovely?
September 30th, 2008 at 8:43 am
@Davidlpf
Not sure if Sarah Palin is an expert on interplanetary affairs or not but I’ve heard that she can sometimes see Mars from her house.
September 30th, 2008 at 9:02 am
Not sure if Sarah Palin is an expert on interplanetary affairs or not but I’ve heard that she can sometimes see Mars from her house.
No silly… that is the moon. M – O – O – N. Moon. And that spells moon…
September 30th, 2008 at 9:51 am
@Davidlpf: I think Sarah Palin did live at high altitudes for a while, so wouldn’t that make her a Mars expert- since she lived so much closer to it than most people?
September 30th, 2008 at 11:25 am
Hey, that’s the snowman from North St. Paul, MN. It’s half a block away from my dentist’s office.
September 30th, 2008 at 11:47 am
Please point out a significant source of calcium carbonate that’s not related to a biological process.
I’ve been looking for some since you suggest there isn’t a very high correllation between calcium carbonates and life on this planet, but the only two alternative processes I’ve found are either derivative of biology or are very much enhanced by biological processes:
http://www.astrobio.net/news/modules.php?op=modload&name=News&file=article&sid=2596
http://geology.geoscienceworld.org/cgi/content/abstract/27/7/645
September 30th, 2008 at 7:39 pm
@bjn: try looking up “Aragonite” (a polymorph of calcite), “Travertine” or “Ooids” (think shallow-sea kidney stones).
Its true that most of the calcite on earth is biogenic in origin, however that’s a selection effect. life on earth , specifically calcareous lifeforms in the ocean, keeps the concentration of calcium and bicarbonate ions in seawater low by using it to produce calcite and aragonite. if the concentration was greater, you’d see a lot more non-biogenic calcite. so while caves and hot-springs absent of calcareous life forms may not be a significant sources of calcite on Earth, its because there aren’t many places on Earth where life doesn’t have a chance to use it all up. And in those few instances were you do have supersaturation of calcium in seawater, you have both biogenic calcite, and nonbiogenic oolites.
As an analogy, lets look at iron oxide. we see lots of the stuff on Mars in the form of hematite and magnetite, and In fact its another indicator that Mars at one point had liquid water, as both form in aqueous environments. however on earth, most of the iron oxide we mine and use comes from “banded iron formations”. BIFs were formed by ancient cyanobacteria, as a means of handling the oxygen they produced through photosynthesis. they took iron ions out of sea water to bond with their waste, leaving behind layer after layer of biogenic rock. we don’t say the the iron oxides on Mars must be biological in origin though, because its clear that in the absences of life, chemical processes could have just as easily rusted surface iron.
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