Sol 90+, Extended mission |
Sol 90+, Extended mission |
Sep 30 2008, 01:31 PM
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#301
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Member Group: Members Posts: 753 Joined: 23-October 04 From: Greensboro, NC USA Member No.: 103 |
Well.. the article says "NASA's Phoenix Mars Lander has detected snow falling from Martian clouds." so not from a cloudless sky. It seems to be real snow. Jim Whiteway, interviewed in today's Washington Post, doesn't mention the particles coming from clouds. "Whiteway said the snow, along with frost and fog, began to appear about a month ago, as temperatures cooled on Mars. "This is now occurring every night," he said. In an interview after the teleconference, Whiteway likened the snow to "diamond dust" that falls in the Arctic and Antarctica. "What this is telling us is that water does rise from the ground to the atmosphere and then precipitates down," he said. "So there is a hydrological cycle on Mars, and now other experts will study the data and try to determine what it all means." Although the Phoenix instruments could not determine whether the snow hit the ground, Whiteway said there are some indications that it does. -------------------- Jonathan Ward
Manning the LCC at http://www.apollolaunchcontrol.com |
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Sep 30 2008, 02:25 PM
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#302
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Senior Member Group: Members Posts: 2173 Joined: 28-December 04 From: Florida, USA Member No.: 132 |
Jim Whiteway, interviewed in today's Washington Post, doesn't mention the particles coming from clouds. I don't know whether the lidar imaging of atmospheric ice crystals and of "snow" falling from clouds are two different observations or two descriptions of the same observation. Phoenix lidar sees snow falling from Martian clouds http://planetary.org/blog/ ...The beam detected clouds at elevations between 3.5 and 4 kilometers above the surface. As the observation continued, it detected "fall streaks," where ice crystals that formed within the clouds began to descend toward the ground... Credit: NASA / JPL / UA / MET team |
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Sep 30 2008, 02:31 PM
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#303
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Member Group: Members Posts: 198 Joined: 2-March 05 From: Richmond, VA USA Member No.: 181 |
Can't find the reference now, but I saw it described yesterday as "diamond dust" Ooooooo. Diamond Dust! If true that could provide some unique pictures (http://www.atoptics.co.uk/halo/diamonds.htm). I was looking for an illustration I did a number of years ago simulating both water and CO2 diamond dust on mars, but I can't find it now. I'll post it if I run across it in a reasonable amount of time. Concerning, your observation efron, I can see both word uses fairly easily being used for the same observed phenomena: 1) you can have ice crystals precipitating from martian clouds that would be more akin to diamond dust than what we think of as snow in nature, and 2) you could have a layer in the atmosphere producing diamond dust which subsequently settles ground ward and is referred to as 'snow' for the ease of communication. [hmmm -- my post is already out of date! That's what I get for digging through old cd's while posting!] -- Pertinax |
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Sep 30 2008, 02:39 PM
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#304
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Newbie Group: Members Posts: 13 Joined: 19-December 04 Member No.: 125 |
Has TEGA detected any nitrogen? Dr. Hoffman gave a presentation at UT Dallas last week. He mentioned that compressed Nitrogen (from earth) was used to move gasses from the ovens to the mass spectrometer. They will not be able to measure nitrogen because of that. I asked if Dr. Hoffman's device had been able to measure the isotopic ratio of Methane in the atmosphere and he answered "Not yet.". |
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Sep 30 2008, 06:03 PM
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#305
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Senior Member Group: Members Posts: 4251 Joined: 17-January 05 Member No.: 152 |
The RAC took a dust devil horizon sequence on sol 111. If you look closely, there are changes (lightening and darkening) near the horizon in some of these frames. Here's the difference between the frames at 11:43:17, 11:44:28, 11:45:37, 11:50:44 and the frame at 11:32:48, turned into a gif movie:
My first thought was these are DD tracks and the devils passed between frames. But I don't think that can be - DD tracks we've seen before form and then stay put. Instead, could these patterns be shadows of thin clouds shifting across the ground? |
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Oct 1 2008, 04:34 AM
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#306
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Member Group: Members Posts: 144 Joined: 17-July 07 From: Canberra Australia Member No.: 2865 |
*cough*cough* Also, I think that the 'fuss over snow' is justified. A snow report is a hook to hang the rest of your science on. Great and open outreach! Astro0 Oh. I see. Sort of like the ESA report of clouds on Mars. But hold on a tick - that got a *scoff*scoff* as opposed to a *cough*cough* |
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Oct 1 2008, 06:45 AM
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#307
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Member Group: Members Posts: 568 Joined: 20-April 05 From: Silesia Member No.: 299 |
Ten days without new Happy Pan images. Is Happy Pan abandoned ?
-------------------- Free software for planetary science (including Cassini Image Viewer).
http://members.tripod.com/petermasek/marinerall.html |
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Oct 1 2008, 07:26 AM
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#308
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
They will be able to carry on taking it after arm-ops are over, so it's more important to do what is necessary in support of arm ops first.
Doug |
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Oct 1 2008, 07:37 AM
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#309
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
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Oct 1 2008, 01:33 PM
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#310
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Senior Member Group: Members Posts: 2517 Joined: 13-September 05 Member No.: 497 |
Because clouds on Mars were not a new discovery, not a unique new finding. Snow is. Snow was observed by MOLA on MGS: http://ssed.gsfc.nasa.gov/tharsis/clouds&snow.html -------------------- Disclaimer: This post is based on public information only. Any opinions are my own.
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Oct 1 2008, 01:39 PM
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#311
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
AH - ok - that I did not know - thanks for pointing it out.
""Nothing like this view has ever been seen on Mars," said Jim Whiteway, of York University, Toronto, lead scientist for the Canadian-supplied Meteorological Station on Phoenix. "We'll be looking for signs that the snow may even reach the ground."" The difference, I think, is that MOLA is saying they saw CO2 snow, PHX is saying H2O snow. But in many respects 'nothing like this view has ever been seen' is true only because we've not had a LIDAR on the surface of Mars before. |
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Oct 1 2008, 02:02 PM
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#312
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Forum Contributor Group: Members Posts: 1372 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
H2O snow. Can Phoenix build a snowman later ?
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Oct 1 2008, 02:22 PM
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#313
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Senior Member Group: Members Posts: 2173 Joined: 28-December 04 From: Florida, USA Member No.: 132 |
In the wildest dreams category, imagine snowflakes reaching Phoenix's microscope substrate wheel!
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Oct 1 2008, 04:50 PM
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#314
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Senior Member Group: Members Posts: 2922 Joined: 14-February 06 From: Very close to the Pyrénées Mountains (France) Member No.: 682 |
In the wildest dreams category, imagine snowflakes reaching Phoenix's microscope substrate wheel! Rui, please do NOT use centsworth_II's avatar when you want to post your wild ideas -------------------- |
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Oct 1 2008, 05:11 PM
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#315
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Senior Member Group: Members Posts: 2173 Joined: 28-December 04 From: Florida, USA Member No.: 132 |
ULTREA!
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