Phoenix Site Options

[helvick]

Bruce, I really wonder about that.  I really think Phoenix, while a cool mission, will sudder from the MER comparison and  cause a lot of people to sit back and say "No immobile missions anymore."

I don't know - it depends an awful lot on what you're trying to do. Landers that gather long term weather data (Tau, insolation, ambient temperature, ground temperature, sky temperature profile, wind speed and direction, high energy radiation, atmospheric composition) or that have a primary aim of putting an array of really good seismometers on the ground don't need to be mobile at all.

IF target selection and EDL are good enough then the Phoenix team should be able to avoid landing on a large slab of bedrock, that's the most likely situation I can see that would prevent the soil analysis experiments.

I'm really looking forward to Phoenix and live in hope that with less of an imaging bias that Nasa will feed out more data from the other sensors on a regular basis. In any case I'm going to be cheering the little Fire Bird on all the way.

[Guest_BruceMoomaw_*]

Network missions aside (and of course very small landers that carry out seismic, weather and other network science will be immobile), there are going to be too general types of big Martian landers from now on: rovers and drillers. The latter are crucial to explore the very scientifically important Martian subsurface, but they're also going to stay in one place. Phoenix is the very first of this category of lander, albeit a specialized version.

[RNeuhaus]

I think that the "main problem" of the Phoenix Mission is the budget restriction. I am sad of this. It is like to take a very expensive trip to a very exotic place at another side of Earth to visit only for 3 days instead of one month in order to be satisfied with the spent money.

So that Phoenix mission would be more worth is that it can

1) last longer than few months, perhaps one to two Mars years to work as a full edition meteorological and seissmic station,
2) be able to drill as deep as many meters,
3) by able to hop to a another close interesting place (remains fuel will freeze???, what happens with during its cruise travel to Mars for many months in a very cold space -don't really know what is the real Kevin temperature is in the space- without freezing the fuel?? as Doug has said previously).

Rodolfo

[djellison]

1) last longer than few months, perhaps one to two Mars years to work as a full edition meteorological and seissmic station, 
2) be able to drill as deep as many meters,
3) by able to hop to a another close interesting place (remains fuel will freeze???, what happens with during its cruise travel to Mars for many months in a very cold space -don't really know what is the real Kevin temperature is in the space- without freezing the fuel?? as Doug has said previously).

Rodolfo

1) Cant happen with solar power - you'd need a big, heavy, unavailable, expensive RTG.

2) You'd need a much larger spacecraft to do that

3) All sorts of reasons why phoenix cant do that

What're you suggesting isnt changed to Phoneix - is a $1Bn mission all of its own called Mars Deep Drill

Doug

[RNeuhaus]

1) Cant happen with solar power - you'd need a big, heavy, unavailable, expensive RTG.

2) You'd need a much larger spacecraft to do that

3) All sorts of reasons why phoenix cant do that

What're you suggesting isnt changed to Phoneix - is a $1Bn mission all of its own called Mars Deep Drill

Doug

Very big tag price!! Re-thinking, I would prefer to save some money of Phoenix to be put for MSL project.

Rodolfo

[djellison]

Phoenix is important as a GRS groundtruth for near sub surface ice. It's work that needs to be done as part of the grand scheme of things.

Doug

[Phil Stooke]

Bruce said:

"As a way to investigate Meridiani (as was originally planned), Phoenix would have been a fiasco. "

I hadn't heard this about Meridiani. Can you tell us more, Bruce?

Phil

[tedstryk]

1) Cant happen with solar power - you'd need a big, heavy, unavailable, expensive RTG.

2) You'd need a much larger spacecraft to do that

3) All sorts of reasons why phoenix cant do that

What're you suggesting isnt changed to Phoneix - is a $1Bn mission all of its own called Mars Deep Drill

Doug

With the way the program works, I would add that we are thinking falsly if we think that "hmmm...., instead of Phoenix, why don't we save up a few more years for a bigger mission?" If we didn't launch Phoenix, that money would probably be allocated out of the Mars program. And without Phoenix, the Mars program would currently have no projects in advanced development, making it a dangerous target for budget cutters.

And I don't agree with the three days to a month analogy. It is more like going to visit a college before deciding to go study there. Sure, Phoenix is limited in scope, but in addition to doing good science, it will help us prepare for when a real drilling mission like Mars Deep Drill is designed. Sort of like how Pioneer was sent to scout for Voyager. The Pioneers made many discoveries in their own right, but also did a lot to prepare the way.

[tedstryk]

Bruce said:

"As a way to investigate Meridiani (as was originally planned), Phoenix would have been a fiasco. "

I hadn't heard this about Meridiani.  Can you tell us more, Bruce?

Phil

I think he was referring to the fact that this was going to be the site for the Mars 2001 lander. It might have been frustrating, but not if it landed where it did. I think Marie Curie, which would have flown on that mission, would have at least been able to explore the Eagle outcrops. And such discoveries might have allowed for MER to carry better-suited instrumentation (actually, probably not much, given the lack of time between the missions, unless one of the MERs were delayed. But for Phoneix, there is a much longer gap before the proposed drilling mission).

[Guest_BruceMoomaw_*]

Yeah -- it was actually sloppy language on my part; I was referring to the originaly planned mission of the 2001 Mars Surveyor Lander (after they stripped it of its REAL initial mission of being the landing platform for an MER rover. As a stationary lander, its ability to study the phenomena of Meridiani would of course have been pathetically limited, and the additional data its MECA package would have obtained would not remotely have been an adequate exchange for that loss.

But, regarding Phoenix: inspection of the Martian ice -- as soon as possible -- is a very important goal in the overall program, and one that simply cannot be done with MSL because of the limitations on its landing latitudes. We need to know more about the potential that the ice may have as a domicile for extant Martian microbes -- and we need to know more about Mars' climate cycles, both over periods of just a few years and over its 150,000-year long obliquity cycles (as ice is repeatedly deposited and then removed again from various latitudes). This mission is the perfect way to do that relatively cheaply and quickly. Any time you're tempted to gripe about it, just remember what I said earlier: this is the very FIRST biological space mission to another world since Viking. If it finds complex organic compounds in the ice, it is going to get extremely interesting extremely fast.

[tedstryk]

Yeah -- it was actually sloppy language on my part; I was referring to the originaly planned mission of the 2001 Mars Surveyor Lander (after they stripped it of its REAL initial mission of being the landing platform for an MER rover.  As a stationary lander, its ability to study the phenomena of Meridiani would of course have been pathetically limited, and the additional data its MECA package would have obtained would not remotely have been an adequate exchange for that loss.

Yes, but it had Marie Curie, with a properly-set-up and brush-equiped APXS, had it landed where Oppy did, it could have done a lot of science. Not as much as an MER, but it definitely wouldn't have been the waste you describe.

[Guest_vjkane2000_*]

we need to know more about Mars' climate cycles, both over periods of just a few years and over its 150,000-year long obliquity cycles (as ice is repeatedly deposited and then removed again from various latitudes). This mission is the perfect way to do that relatively cheaply and quickly.

While I agree with Bruce on the importance of these topics, there is a substantial chance that Phoenix's results will be inconclusive about both them and any biology. Just as with Deep Impact, this is a new terrain that we know very little about. Any of many factors -- like landing a few meters away from the right site or some type of soil gardening that erases context -- could prevent us from learning much about these goals.

That said, I think it's worth the effort. We need to take risks and then not blame the spacecraft team if we get skunked.

[tedstryk]

While I agree with Bruce on the importance of these topics, there is a substantial chance that Phoenix's results will be inconclusive about both them and any biology.  Just as with Deep Impact, this is a new terrain that we know very little about.  Any of many factors -- like landing a few meters away from the right site or some type of soil gardening that erases context -- could prevent us from learning much about these goals.

That said, I think it's worth the effort.  We need to take risks and then not blame the spacecraft team if we get skunked.

I agree. I know there are those who insist that we should send a mobile vehicle with a large drill that can also take more samples, etc., etc. Well, while we're at it, why don't we put a manned module in orbit to control the rovers in real time. And, add sample return capacity, of both soil, rock, and ice cores. Sure, there are limitations of the mission thanks to budget, but that is just reality.

[algorimancer]

As for Europa, the icy surface is of little interest compared to the depths, but even there some horizontal discretion could be the difference between boom and bust...

I suspect that dismissing the importance of roving capability on Europa will turn-out to be short-sighted. We have pretty-near zero experience on the surface of an icy satellite (barring those fuzzy pics from Titan, which isn't a conventional icy satellite). At the very least, surface ice is likely to have originated from the internal ocean, and analysing the ice could reveal evidence of organic chemistry and (perhaps) life. It may be useful to have the capability to drive a few kilometers to find more recently exposed ice, and who knows what interesting "eurology" might be encountered.

[Guest_BruceMoomaw_*]

Detection of relatively recently exposed ice -- or, more precisely, ice with a lot of other stuff mixed in (particularly organics) -- is indeed important, but the current emphasis is on doing it from orbit and then dispatching landers to those spots to probe it vertically.