Without wheels it's stuck with samples from just a few feet. Is this just a redo from a new location? Would the $00 million be better spent on the Mars science lab project?

What if the Phoenix mission objective was such that it could be completed successfully without requiring wheels? In that case wouldn't it be a wise and productive conservation of resources (which could then be used for other missions) not to burden Phoenix with components it did not need?

Isn't that making a generalization based on a 9 foot circle? It could land on a patch of clay and not find frozen water. But 20 feet away could be ice. Hasn't the two MERs taught us just how diverse Mars is? $400 million for 3-4 holes in a narrow circle when next year we should have another rover capable of traveling dozens of miles just seems silly.

They picked the landing point in part for its uniformity.

Winter will come soon to the northern latitudes, and a wheeled vehicle under meters of dry ice isn't useful.

It was built from the "ashes" of 2001 Mars Surveyor lander. It didn't have wheels. The budget couldn't add wheels. Landers are cheaper than rovers.

NASA has had a pattern of alternately sending landers and rovers (and orbiters) to maximize coverage economically.

NASA Phoenix mission

Did you consult the University of Arizona Mars Phoenix FAQ?

__________________
0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 ...

Plus, it's named after our first female X-Man. That in itself is cool. ;-)

__________________
Rovers forever! - ToSeek
"The only way to explore the universe is to go and look." - Brian Cox
Well, the best way to find out is to go there and, find out. - Raven's Cry
'Evolution and science are one thing, but you don’t mess with Yoko Ono. Everybody knows that. ' - 386sx

"and a wheeled vehicle under meters of dry ice isn't useful."

I doubt a lander under meters of dry ice would be much use either.

It sounds like they already know it's there so is the mission justified?

Picture this. Day two after the landing ...

They dig a hole and scoop the soil into the experiment chamber 1. Turn on the equipment and bingo! positive for water ice.

Is there a point to continue with the mission? Should they dig a second hole 4 feet from the first? I wonder what they would find? Duh maybe water ice???

Of course, but it's far cheaper. It will be a long, long time before someone invests in a polar rover that has such a short potential drive. It will happen eventually. The time is not now.

Duh. Have you read Phoenix Mission objectives and methods? It doesn't match your scenario.

__________________
0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 ...

The questions Phoenix is designed to address don't need mobility.

Mobility is expensive. Rovers cost twice as much per kg as stationarly landers and have much smaller payloads. they are much more complex to design and operate. if you don''t need it you don't have it.

Especially when this is a minimum cost scout mission!

The questions Phoenix will address have been waiting since Viking, there have been four other attempts to address them, all failures. It is time they were answered. MSL won't address them, it has its own quite different mission goals with a different instrument suite. And MSL is a much later mission with no assurance of success.

Jon

Viking 2.0 is not neccesarily a bad thing.

There are LOTS of areas on Mars we haven't touched yet, especially up in the near-polar areas like this where life-compatible conditions (or at least where life may have held out the longest) may be readily detected.

A whole bunch of Viking 2.0's would be a good thing....

Phoenix mission goals are not predicated on finding a patch of ice. Although it would be nice!

And Phoenix costs significantly less than a rover. Plus its sensitive chemical lab is not ideal for a rover mission. Different goals, different design.

Jon

Except that Phoenix can complete a useful mission in a few months. We now expect years of operation froma rover. Could a rover be designed to oeprate at high laatitides and do useful work in a few months? yes it could, but it would not be another MER but a nw vehicle. And it could not carry the Phoenix science suite or address the imporant questions that Phoenix is designed to answer.

have you actually read the mission goals? There is a lot we don't know about soil chemistry, mineralogy, texture, surface properties, activity, meteorology, soil physics etc.

The mission is about more than finding water ice. There are a lot we don't know about soil chemistry, mineralogy, texture, grain surface properties, soil-atmosphere activity, meteorology, atmospheric physics. We don't knwo the texture and archiecture of the area at resolutions of less than 30 cm. We don't know the soil phsyics, a rather important issue for future rover operations.

You need multiple sites to characterise regolith properties. There may be considerable small scale variability, feratures such as patterned ground that need invesigation.

Phoenix is cheap, well thought out, and long over due. I wish you would read more about the mission before criticisng.

Jon

A network of small geophysical and meteorological stations with basic imaging and soil properties instruments is long over due.

Jon

I wish it was a rover, and I complained about it a long time ago. But I am really excited to see some "ground truth" from a Martian polar region. This could be really really interesting!

__________________
"I'm as accurate as any psychic. And I'm a cartoon!" -- Squidward

"Arrrgh, the laws of physics be a harsh mistress!" -- Bender

What I don't understand, is why no one has sent a microscope on one of these landers. Instead of just dozen and one chemical tests, that always seem to come back "inconclusive", stick a lens at for petes sake. I admit it is likely a rather difficult task to make a microscope hardy enough for the ride, but then, this is rocket science, ALL of it is 'rather difficult'.

__________________

I wish it were a 20 person expedition! But we take what we are given and are grateful!

Jon

That's why the MERs have a panchromatic microscopic imager with 30 micron resolution, MSL will have a 30 micron resolution colour imager. Phoenix has an atomic force microscope.

Jon

Phoenix MECA - Microscopy, Electrochemistry, and Conductivity Analyzer

__________________
0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 ...

And I wish I was one of those... eh, you're right.

__________________
Rovers forever! - ToSeek
"The only way to explore the universe is to go and look." - Brian Cox
Well, the best way to find out is to go there and, find out. - Raven's Cry
'Evolution and science are one thing, but you don’t mess with Yoko Ono. Everybody knows that. ' - 386sx

not to pick nits, but don't you have to have liquid water in order to have clay? Discovering clay would mean success for one of the mission goals wouldn't it?

__________________
The More I learn, The More Ignorant I Become

Eagle Eye Observatory

Thanks, though it would be great if someone looked at a deep sample and found something. . .wiggling.

__________________