Evidence of Glaciers on Mars?

cyclop writes "Nature reports that the Mars Express mission has photographed evidence of ancient glaciers on Mars. It seems glaciers have sculpted valleys on the red planet, much like on Earth." Reader macguys writes "Space.com is reporting that the Mars Rover Opportunity has received an unexpected and unexplained power boost of between 2 and 5 percent. The NASA Rover site is so far silent on the boost."

Powerboost old news - rover site posted weeks ago

[dtolman]

Rover site is silent on this? Try reading the press releases [nasa.gov] when they come out.

This was posted weeks ago...

The wheel?

[Sporkinum]

Maybe the drive wheel that was stuck freed up and and lowered the load. Or, more likely, a lucky gusty of wind cleaned some of the dust off the solar cells.

Re:Power Boost

[dtolman]

This is over and above that.

A power boost like this means that there is less dust on the panels. Speculation I've seen includes that wind in the crater blew the dust off or that the winter frost somehow condensed the dust so it takes up less surface area...

The vast red plains

[AtariAmarok]

Please see this very recent Slashdot article [slashdot.org] for more about the vast red plains.

Mars Express Images

[mdp1173]

I have to give the European's credit for aestetics if nothing else. The pictures coming back from Mars Express are gorgeous. I don't know how much more science you get out of something like that instead of the not-quite-so-stunning pictures that NASA's probes have yielded, but if you're looking for a neat backgroud and your tired of what's on Digital Blasphemy, ESA has it.

I'm not saying I don't like what the MERs have sent back, but some of the ESA stuff is pretty sweet looking

ESA's Mars Express [esa.int]

Re:Power Boost?

[dtolman]

maybe the ambient light on mars, in the proper spectrum is greater than expected. i.e. a higher number of lumens?

maybe the properties (refractivity/reflectivity?) of the dust have a quality that allows the light to pass through at a greater rate than expected? or is it possible for them to emit a non-visible spectrum which can be used by the solar cells?

Having two identical rovers on Mars rules out these theories. Whatever is happening is specific to one rover and not the other - so it can't be atmospheric, and it probably isn't dust related - since the dust is virtually identical (and equally opaque) at both sites.

On top of that - the rover did have decreasing power output over the past year - so something changed to reverse that trend...

Re:The wheel?

[dtolman]

Maybe the drive wheel that was stuck freed up and and lowered the load.

The stuck wheel was on the rover Spirit -this article is about the other one, Opportunity. So no go on that theory. In any case, this change is in the incoming power, not the power expenditure - so changes in the wheel wouldn't change anything.

Re:Power Boost

[dtolman]

Doesn't frost require water? If not, what other substance can cause it at those temperatures?

Other substances can condense at the low temperatures on Mars. I think most of the time the primary component of Martian frost is CO2 - Carbon Dioxide. CO2 frosts were documented by the two Viking landers - so this is a known (though I have no idea how well understood) phenomenon.

understood just fine

[pyr0]

http://www.co2clean.com/snowform.htm [co2clean.com] Or, in other words, dP/dT=deltaS/deltaV

Re:Powerboost old news - rover site posted weeks a

[stevesliva]

Specifically, here. [nasa.gov].

Very difficult to find-- I had to go to the Opportunity updates page and search for the first occurence of the word "power."

glacial valleys verses river valleys

[peter303]

Glaciers carve rounded "U"-shaped valleys while rivers make pointed "V"-shaped valleys. You can distinguish the two in places like Yosemite and Denali which have valleys of both kinds in the past 15,000 years. The geologists were seeing this in the Mars photographs.

Re:Why Mars?

[cjameshuff]

The magnetosphere isn't a significant factor, Mars likely just never had much of an atmosphere to start with. As a counterexample, Venus gets about 4.45 times as much solar radiation as Mars, has no significant magnetic field, and has a weaker surface gravity than Earth, yet it has far more atmosphere than Earth.

To the parent:
Mars has rather sparse amounts of nitrogen...you're probably going to bring that from Earth either way. Other than that, the moon has everything Mars has, it's a shorter duration trip, the shorter communications lag makes ground control feasible for more things, and it has less gravity to overcome for launch or landing. (Mars has enough atmosphere to make trouble on reentry, but too little to make soft landings easy.) Also, the atmosphere has combined with any free metals on the surface of Mars...this is not so on the moon.

Mars is interesting as a potential life-supporting body...studying a biology that originated on another planet could give us new insights into that of our own world. However, I don't see it as a useful colonization or industrial target.

Re:Powerboost old news - rover site posted weeks a

[captainClassLoader]

This is a different power increase from the gradual one reported on in the earlier press releases. The space.com article is dated November 4th, and refers to 2-5% power increase overnight. The best candidate for an explanation seems to be that Opportunity was targeted by a dust devil that blew almost all of the dust off of it - And the rover is now at 82% full power, a condition it hasn't experienced for months. Talk about luck!

Re:Power Boost

[MichaelSmith]

CO2 frosts were documented by the two Viking landers - so this is a known (though I have no idea how well understood) phenomenon.

Yes, but the rovers are both too warm for CO2 to form frost on their solar panels.

Solid carbon dioxide on Mars is as rare as solid water on Earth. It will collect on reallycold surfaces near the poles in winter. Electronic devices, even when mostly shutdown for the night, are warm enough to vaporise CO2 from their surfaces