Comments on: Phoenix: "It Must Be Ice"

By: Hassan Moazi

Hassan Moazi — Sat, 25 Oct 2008 09:02:40 +0000

man Akharesh nadoonestam in aab rooye merikh peyda shode ya Naaaa??!!!

By: Kevin M.

Kevin M. — Sat, 21 Jun 2008 17:57:10 +0000

I was under the impression that the University of Arizona was running these experiments, not NASA.

By: GI Joe

GI Joe — Fri, 20 Jun 2008 18:44:41 +0000

I'm ready to go to Mars, SIR!!

By: J. Mattair

J. Mattair — Fri, 20 Jun 2008 18:31:46 +0000

Bobby, you asked good questions. I think the reason the isolated chunks of ice sublimated (goes directly from solid to gas) so quickly is that those pieces were insulated from the rest of the buried ice layer by soil. Water conducts heat quite well. The isolated pieces were warmed by the Martian air and exposed to ambient light over most of their surfaces. However, the buried ice layer was only exposed on the top surface. The rest of the buried ice layer pulls away heat from the surface, due to the high heat conductivity of water.

As far as the "white" chunks that didn't sublimate, they are not composed of the same material. Remember that these are not the same black and white photos you are used to. Each image is taken at a specific wavelength (color) using color filters. The images where the ice appears brightest are taken at the blue end of the spectrum. Blue photos are usually exposed much longer so the ice seems brighter in them. Looking at the chunks that didn't sublimate using different filters reveals that they are different from the ice. A false-color animation is available at http://www.probetracker.com/lg_5251_c2_animate.gif

By: Bill

Bill — Fri, 20 Jun 2008 17:45:32 +0000

The Mars researchers all say that the polar caps of Mars are predominately carbon dioxide, so there is little to think that carbon dioxide cannot exist near the martian poles. That alone makes it more likely that this is CO2. At the Phoenix website or the Planetary Society's blog page, there is a two frame animation of the disappearance of the white stuff. If you look carefully, there is also dark stuff, some small chunks, that disappears, and it's not just a change in shadow. Now what could that mean? If the dark stuff is neither water or CO2 ice, how to explain it? If I' m not hallucinating, and if the dark stuff is not an ice, then there is something present that can make small quantities of mineral go away.

By: Astrofiend

Astrofiend — Fri, 20 Jun 2008 17:06:15 +0000

Bobby Says:
June 20th, 2008 at 6:40 am
"Not convinced at all. Sounds to me like the scientists are trying to make these images "fit" their paradigm."

Well, when you see something disappear before your eyes, and you already know that water ice is not far below the surface from measurements made by other spacecraft, I think it is well within reason to make that leap. I guess it's a good thing they have loads of equipment on board that will soon be able to tell us for sure.

By: Benudhar,India

Benudhar,India — Fri, 20 Jun 2008 16:40:04 +0000

I think it may be ice.It is looks very white.It is very exciting news for us.

By: Aodhhan

Aodhhan — Fri, 20 Jun 2008 15:23:38 +0000

I'm not sure it gets cold enough to freeze carbon dioxide, although with a low pressure it could be a lot higher than normal.

Anyone have an idea what temperature CO2 freezes at Mars' low pressure?
Been a long time since I've worked through phase diagrams to figure this out.

By: Bill

Bill — Fri, 20 Jun 2008 15:12:40 +0000

Could be carbon dioxide ice. It sublimated rather quickly.

By: Molecular

Molecular — Fri, 20 Jun 2008 14:52:30 +0000

I'm not sure how powerful that arm is, or if the intensity of the scooping can be increased, but, why don't they just go over the same dig until more ice is revealed at the surface? Either that, or just dig deeper into the same hole, thus bringing up more ice?

By: RL

RL — Fri, 20 Jun 2008 14:05:43 +0000

Even though it may look like ice and behave like they would expect (and they are probably right), I would be more confident of this analysis if they confirm this by test. As far as I remember, only one test has been done so far, correct? The first test was negative for H2O but NASA was working out the testing procedure (getting the sample into the oven). Does anyone know when NASA will try again? Do they have to wait for the FLASH memory fix?

By: Bobby

Bobby — Fri, 20 Jun 2008 13:40:57 +0000

Looks to me like there are big white chunks just outside the scoop trench (at the top of the picture) that haven't changed between the two pictures. Why hasn't that evaporated?

And, I still see white inside the trench, so only some of the "ice" evaporated?

Not convinced at all. Sounds to me like the scientists are trying to make these images "fit" their paradigm.

By: Kevin White

Kevin White — Fri, 20 Jun 2008 13:40:39 +0000

Not possible the wind blew the particles out?

Sounds great!

By: Aodhhan

Aodhhan — Fri, 20 Jun 2008 13:03:57 +0000

I'm not thoroughly convinced yet, but it is (to me) the best news to come from this program yet. Definitely exciting!