Frozen water on mars?

[Bandersnatch]

Looks like it.

 

[Nucular]

Well I thought it was interesting, even if no-one else did.

I was quite intrigued by the contamination (seepage of surrounding rock/sand crap?) in the top left area of the ice. In the hi-res version of the picture, you can see shades of green. Artifacts of the imaging/colourisation process? Or could it be algae?? (or a group of little green men staring at the UFO?)

 

[Bandersnatch]

I probably should have added "Besides the ice caps."

I didn't notice the discolouration on first glance, cool.

 

[GrnMtSkeptic]

(or a group of little green men staring at the UFO?)

OMG, yes! And that dark mass intruding into the ice is their trailer park!

From the FAQ:

What are the green/blue patches we see in some of the images?

The colour of the greenish patches in Gusev crater in the first image released of this site is not correct. Unfortunately, an early version of Gusev image was released before the colour had been adjusted finally to be closer to true colour as the human eye would see it in a non-dusty atmosphere of Mars.

The early version of this image was replaced by a newly computed version with proper colours where the patches are grey to black with a blue tint. This is close to what a human eye would see under normal atmospheric conditions. Currently it is not easy to get true colours of the Martian landscape because Mars is very dusty and the scenes were taken with high sun angles. The scattering of light caused in these atmospheric and lighting conditions, by the dust in the atmosphere acting as tiny red filters, means that you see the surface with a diffuse reddish glow with somewhat fuzzy appearance.

Are the colour photographs processed?

Yes, the images have been processed but that is quite normal. We are not taking colour photographs, we have to combine the different colour channels which requires processing time. Each of the four colour channels operate with a filter of different wavelength (red, green, blue and infrared) and produce data sets which have to be combined and calculated on to a digital elevation model.

The colour channels are absolutely real, but they do not reflect the true colour as we would see it with our eyes. These views can be obtained by processing the data, which does not mean ‘faking’ the colours, but fitting them to standard spectral curves which we know. We adjust the obtained colour image data to a standard spectral curve derived from Earth-based observations in terms of wavelength and intensity.

If we have dust, haze or other atmospheric conditions, various wavelengths get partially filtered. Obviously, images get more blurry and some colours become more dominant. Sun-exposed slopes reflect or absorb light in a different way to dark slopes or dark material (such as dark spots of possible sediments seen in some images).

The main limitation, of course, is that from orbit we do not have any colour adjustment possibilities as for example, the NASA rovers. They have colour references mounted on their rovers and even they have problems matching their colours.

So I'd suspect an artifact of the imaging.

 

[athon]

So I'd suspect an artifact of the imaging.

Of course, that's what the government wants you to think.

I think it's a LGM protest rally against the 'human' invasion.

Athon

 

[TheBoyPaj]

I thought it was interesting. In fact, it has been on my desktop all week.

 

[Nucular]

From the FAQ:



So I'd suspect an artifact of the imaging.

Hmm, yes, I hadn't read the FAQ. Could be, but it's hard to know which green on the Gusev photos they mean.

I'm guessing it's this bit on this photo:

Which has a similar colour to the green in the ice I guess, but you'd think they'd have mentioned it specifically. Maybe they will.

I did notice that the green is all around the edge of the ice, not just that corner. That might be where you'd expect to see algae? At the edge, the shallow bits most easily warmed by the sun... maybe with a thin crust of solid ice somehow, to stop it simply boiling off into the low-pressure atmosphere. Nice thought.

(Also, where those trailer park LGM would run for cover...)

(ETA: just realised the FAQ says the Gusev pic has now been corrected, so obviously the bit I just posted is supposed to be accurate)



On a related note, my Dad's just remarked, why wouldn't this ice be covered by dust? Mars has just had a planet-wide dust storm, and it's not exactly dust-free at the best of times. Why does this ice look so pristine? You'd think it was brand new...