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Unmanned Spaceflight.com _ Phoenix _ Mission Success Criteria

Posted by: dvandorn Jul 22 2008, 07:27 AM

It's currently halfway through Sol 56. We have, to this point, accomplished the following (please correct me if I'm missing anything):

- Full Mission Success stereo color pan of the entire landing site

- Full RAC coverage of what it can view under the lander

- One TEGA run

- One WCL run

- Two OM images of soil

- Zero AFM images of soil

- Programmed observations of winds and temperatures

How far, with only 34.5 sols left in the 90-sol primary mission, does that leave us from accomplishing the Mission Success Criteria? (Capitalized so that, as Steve Squyres noted, if you fail to accomplish them you'll know that You Have Failed.)

I understand that things are working well enough that we can likely count on a good 30 sols of full mission activity past the base 90-sol mission. Even at figuring that in, we appear to be nearly halfway through Phoenix's entire useful lifetime.

Are we seriously in jeopardy of failing to achieve some of the success criteria?

-the other Doug

Posted by: jamescanvin Jul 22 2008, 08:38 AM

For reference

QUOTE

Minimum Mission Success

1. Land successfully on the surface of Mars and achieve a power safe state.
2. Acquire a partial 120° monochromatic panorama of the landing site.
3. Provide samples of the surface soil as well as samples from one depth beneath the surface to either
TEGA or MECA wet chemistry.
4. If TEGA, analyze at least 2 soil samples to create a profile of H2O (in the form of hydrated minerals,
adsorbed water, or possibly ice at the deepest level) and mineral abundances near the surface. It shall
also analyze an atmospheric sample in its mass spectrometer.
5. If MECA, analyze the wet chemistry of 2 soil samples.
6. Document all non-atmospheric samples and their collection locations with images.

Full Mission Success

1. Land successfully on the surface of Mars and achieve a power safe state.
2. Acquire a true color (RGB), 360° panorama of the landing site
3. Obtain calibrated optical spectra of at least 3 locations that include both rocks and soil.
4. Provide temperature and pressure measurements throughout landed surface operations at a frequency
that determines key atmospheric properties.
5. Provide samples of the surface soil, and samples from two depths beneath the surface, to both TEGA
and MECA.
6. Use TEGA to analyze at least 3 soil samples to create a profile of H2O (in the form of hydrated
minerals, adsorbed water, or possibly ice at the deepest level) and mineral abundances near the
surface. It shall also analyze an atmospheric sample in its mass spectrometer.
7. Use MECA to analyze the wet chemistry of at least 3 soil samples. It shall also analyze 3 additional
samples in its microscopy station.
8. Document all 9 non-atmospheric samples and their collection locations (before and after sampling)
with images.

http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/40351/1/07-0267.pdf

Posted by: Deimos Jul 22 2008, 11:17 AM

By my count:
Minimum--done.
Full:
1-3: 100%
4: 100% or 56/90 or 56/however-long-Phoenix-lasts
5: 3/6
6: 1/3
7: 5/6 (2/3 + 3/3; AFM doesn't matter to formal mission success; it just matters to the pesky scientists)
8: 6/9

Posted by: djellison Jul 22 2008, 12:01 PM

It's worth noting, Opportunity only achieved Full Mission Success 8 sols shy of the 90, Spirit only 2 sols short.

Doug

Posted by: jmknapp Jul 23 2008, 12:03 AM

A good indication is the number of press conferences (live or by telephone) in the last month--zero.

Still, maybe if by some turn of luck things start going better, 10 productive days or so might make up most of the lost ground?

Posted by: tasp Jul 23 2008, 01:34 AM

(If I may, a few funny ones)

* Not landing on an outcropping of anti-matter

* Not setting off an interplanetary war with the inhabitants

* Landing on the right planet

* Not burning up the last trace of vegetation with the landing rockets

* Noticing you have landed next to the last trace of vegetation

* First picture sent back does not show a large wad of duck tape fouling the solar panels

Posted by: nprev Jul 23 2008, 01:48 AM

...reminded of an ancient Mike Peters cartoon that had one of the Vikings radioing back that there was no evidence of life, while a male & female pair of LGMs lay crunched beneath the landing pads...

Posted by: tasp Jul 23 2008, 03:41 AM

LOL, that was what sparked my little outburst there.

Posted by: glennwsmith Jul 23 2008, 05:41 AM

Perhaps Peter Smith has a different conception of this mission than that which UMSF has been accustomed to, and one which has been successfully borne out so far -- not a broad "let's poke around everywhere", but a strategic, surgical strike. After all, they did land right on top of their ice target, which was revealed within a few hours. And now, a single delivery of ice bearing soil to TEGA and the WCL, followed by successful analysis -- which can be accomplished in a few more days -- will triumphantly complete the mission. . .

Posted by: climber Jul 23 2008, 07:35 AM

Trouble is that up to date we had 2 kinds of spacecrafts at Mars :
+ the one that are wayyyyy above mission success. I mean much much above.
+ the one that totaly failed
There's nothing inbetween so we all have HIGH expectations for Phoenix.

Posted by: JRehling Jul 24 2008, 02:38 AM

Some of the requirements are vague in a way that lawyers could argue with, if need be, but I think we really need to have two more successful uses of TEGA in order to confirm detection of organics: One of an ice sample, followed by one test with the blank. If there are no organics, then the blank test would be unnecessary, but then we'd want to test another ice sample followed by the blank test if the second ice sample showed organics.

It's the pacing of success/failure that's unusual. With a flyby or landing, you pretty much find out after failure if it was going to fail. With an orbiter, you might always hope that whatever was wrong will jostle itself into a fixed situation, and you only gradually give up hope. But Phoenix faces a real deadline. I don't know how to measure whether it's ahead of pace or behind pace, but it feels like it's a little behind.

Posted by: nprev Jul 24 2008, 02:44 AM

They may have more schedule margin then we know, though; I'm personally expecting her to hang on at least 120 sols. Failing that, they are obviously proceeding VERY carefully by understanding the sublimation characteristics of the soil and writing a good event script to assure ice delivery to TEGA, which is arguably the signature instrument of the mission.

Posted by: ToSeek Jul 24 2008, 09:22 PM

QUOTE (climber @ Jul 23 2008, 03:35 AM)

That's kind of the rule for stuff in general: either it's well-made so lasts well past the warranty period, or it's junk and breaks right away.

Posted by: tedstryk Jul 30 2008, 10:55 PM

QUOTE (ToSeek @ Jul 24 2008, 09:22 PM)

That's kind of the rule for stuff in general: either it's well-made so lasts well past the warranty period, or it's junk and breaks right away.

Well, at least on the American side. Many of the Soviet missions that actually reached Mars were partially successful but failed to achieve many of the mission goals.