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.

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.
Click to view attachment
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

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[hmmm -- my post is already out of date!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

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.".

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:
Click to view attachment
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?

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*

Ten days without new Happy Pan images. Is Happy Pan abandoned ?

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

Because clouds on Mars were not a new discovery, not a unique new finding. Snow is.

I have sent you a private message.

Snow was observed by MOLA on MGS:

http://ssed.gsfc.nasa.gov/tharsis/clouds&snow.html

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.

H2O snow. Can Phoenix build a snowman later ?

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

ULTREA!

Sol 126 and CO2 "snow".

Ant103,
I think the white stuff is the carbon-free standard for instrument calibration.

Phoenix saw some impressive cloud evolution during a 26-minute long sequence taken on Sol 126. Click through for the animation (difference enhanced 4x, no flat field)


Sol 126, 12:54:37 through 13:20:11

Organic Free Blank material it is.

And I just love to watch it, but I really would like to see those fluffy whites smoothly gliding along at their real speed.
I'm not asking for a computer animation - I worship reality - but can't somebody interpolate between the images?
C'mon, Astro0, if nobody else will condescend!

It's not easy, and it's really not worth much. Your imagination will do a far better job. And, with the techniques I know of - it would take DAYS to do.

Doug

Certainly was impressive!!!!

There's just something about cloud pics on Mars. I've got a couple of great Oppy cloud pics on the wall - coming out of winter at Endurance Crater. I wasn't quite sure of the time signatures but these look like eary morning clouds. Also they look like they could have a convective element? Anyone hazard a guess as to what height their bases might be above the ground? And thickness height? It'll be fascinating to see if the (varga) H20 snow (diamond dust) will reach the ground as the season continues to change.

It'll be nice to get an HiRISE image including clouds and their shadow. I think this will help answering...

That is just awesome!

I took slinted's animation sequence and rereferenced it to the center of the bright cloud you see forming in the right side of the image.
Click to view attachment
(click to launch GIF)

I call it "The short happy life of a cloud in the northern plains of Mars."

(Bonus: the animation makes Phoenix look like a rover!)

-Mike

What about a slow overlapping fade so one image flows to the next?
What about morphing from one image to the next?

About that, I will try it (not very hard with Keynote and flash format export )

In this image from the recent press briefing, ground fog is mentioned. The caption says
I don't recall any mention of this at the briefing. Does anyone have any idea what observations indicated ground fog? Lidar, or SSI? Which SSI images show ground fog?

This is new to me, but it's definitely cool imagining Phoenix surrounded by tendrils of ground fog on these frosty mornings...

Done

http://www.db-prods.net/blog/wp-content/up...oudanims126.swf

Tell me if you think that is good for you

We already have the Bonustal panorama...(ok, bad pun)

Looks great! How much time elapses between first image and last? Would it be practical to have a real time look at how fast the clouds move across the sky or would it be like watching the minute hand on a clock?

Hum… There is about 53 s interval between each frame. I have try it with only 2 pictures, the move of the clouds is very low. I can made a quicktime movie if you want, but i will be "like watching the minute hand on a clock".

Edit : it's very long, more than 15 minutes. And video export doesn't seem to work good.

I believe that was intended as a lidar reference.


I wish! But, look really (really) squinty-eyed at http://www.met.tamu.edu/mars/i/SS109EFF905...3_1C8B0R2M1.jpg and
associated images. And maybe imagine what fog *might* look like someday in this direction, or even suggest another direction (maybe Jack's Hill to the west?).

Walking out the door today for lunch I looked up and the sky overhead here had exactly the same pattern clouds and skies as recently posted for Phoenix.

That was a truly surreal sensation. I can't quite put it in words, but it was really cool....

This image came down recently:
Click to view attachment

the question is for 'someone in the know' about the SSI:
How slow is the SSI (1/8 sec, 1/2 sec 1sec ?) 'exposing' to capture this blurry movement?

Thanks for your efforts, Ant! I was hoping that the winds would be faster higher up.

The telltale exposures are variable, depending on time of day and other sky brightness factors. But 1/2 to 1 sec is typical. The blue filter is used to allow larger exposure times compared to the IR. That makes it easier to separate high frequency variations from the average wind in most cases.

To add to Deimos's comments, if you open the jpeg file in a text editor, there's a header that gives all sorts of juicy details. For the telltale image you posted, the header says , which I believe is in milliseconds, ie that was just over a 3/4 second exposure.

PS - thanks for the ground fog info! Yeah, if I squint hard I can just imagine fog in the distance in that image...

I'm just glad to know the reality of the situation (don't need to see a real time video). Thanks for the sped up version.

Successful search for new Dust Devils - Sol 127.
Click to view attachment
Click to view attachment
Click to view attachment

Sol 128 dust grains colourisation here if anyone wants a look...

Some nice frost detail on this sol 129 colourisation...

Click to view attachment

... and an interesting Peter Smith hinterview here... ("Tucson Citizen")

I know it's a little late, or has already been done, but I'm way behind on these threads. And hey, maybe this'll work for someone too.

I found this site, which gave a dandy little script for AVIsynth. Virtualdub kindly exported the video as a well-compressed GIF file.


Link
It's a little over 2MB.
Maybe it's not at "real" speed, but that'd take a darn long time for a "realtime" file.

But what the heck, my computer does all the hard work, not me, so I'll see what happens if I tinker with that AVIsynth file.
I think sometime tomorrow I should be able to get it working. Right now, the files are coming out way longer than expected - 26 hours, instead of 26 minutes. Virtualdub gives one length, but the actual file comes out much longer.

The file will be an AVI, XVID format, and probably around only 4MB.

That is pretty nice. I've tried to make animations that morph between the frames, but they rarely deliver a file size that fits on UMSF. That is quite nice, even if it was 2 MB.

Hi all

A little mosaic showing the ground and a cloudy sky. I can post it in full resolution (base image are downsampled to 256px)


And the RA working at a trench which I forget his name

That is very nice. I'm sure someone will want to colour it . . .

I see lots of cool animations in this thread!
May I ask to the authors to post them in this thread?
http://www.unmannedspaceflight.com/index.p...c=5510&st=0

I'm trying to collect all cool phoenix animations.
Maybe once I have much of them, I could create a standalone webpage which directly loads all of them, so you don't have to click anyone of them to see!

Then by all means collect them. However, they belong here in this thread - in the flow with other current Phoenix discussions.

Here it is


It was harder that I knew to have "good" colors. So, I'm quite satisfy .

Great job, Ant, a keeper for sure, and that will be shown at my astronomy society meeting tonight, thanks!

Now, looking in the opposite direction, here's an anaglyph showing some recent (Sol129) trenching activities... but I have to warn you, this one will really pull you in when you look at it...

That one is really good Stu. Worth calling the kids over to have a look. You guys who do slide shows with anaglyphs to groups, need to include this one.