NASA's Phoenix Finally Fills Oven

JoeRobe writes "Phoenix has successfully filled oven #4 of the Thermal and Evolved-Gas Analyzer instrument (TEGA). They have spent several days now vibrating the screen above the oven, trying to get a significant amount of soil sample into it. From the article: '[T]he oven might have filled because of the cumulative effects of all the vibrating, or because of changes in the soil's cohesiveness as it sat for days on the top of the screen.' Either way, this is the first step toward getting some interesting data from this instrument."

Re:invalidate the tests

[osu-neko]

couldn't this invalidate the tests.

I don't think so. What would they be testing for that would be invalidated by this? If they find presence of life, or evidence of past life, the fact that they screened something out doesn't invalidate what they found in what was left. If they fail to find anything like that, there's no valid conclusion that could be drawn in any case (absence of evidence is not evidence of absence), so a conclusion of "there's no life and never was" would be invalid regardless of whether parts of the sample were screened out or not.

In short, if it's a partial sample, it reduces the odds of success, but does not invalidate any result.

Re:What were they thinking?

[SBacks]

Why would they have designed the thing to have such a low tolerance filter in the first place?

Cuz they had to strap it on a rocket and shoot it to Mars? I kinda doubt a full sized lab furnace would be under the weight requirement.

Re:invalidate the tests

[osu-neko]

There's no such thing as a "false negative" for the kind of tests they're doing. They're not conducting the kinds of experiments that would falsify a theory. The only results possible from the tests they're doing are "confirmed" or "failed to confirm" (and nothing much can be concluded from the latter in any case).

Re:What were they thinking?

[drrck]

We're talking about introducing material into an oven to be vaporized for Mass Spec analysis. You don't want or need to deal with huge amounts of material to tell what compounds are in the soil.

Re:invalidate the tests

[cetitau]

I don't want to sound like an expert in this field but I don't understand this response. This science doesn't look for life. Here it's looking for some specific chemical content in the oven at the conclusion of the test. If clumpiness was a result of soil mixed with frozen volatiles, i.e. soil particles stuck together by water or other ices, then evaporation of the volatiles over these days of shaking could certainly alter the outcome. I believe none of these tests are designed to prove or disprove the existance of life on Mars, only to produce results that could indicate or contraindicate the possibility that life could exist or could have existed at some time. The only sure proof would be a video of a drunk Martian Cubs fan stagering home after yet another loss at the park.

Oven #4 is the first oven?

[otter42]

From my reading of the FA, it seems that oven #4 is the first oven they tried. That's important, because it seems that whether the soil gets there or not, they only get one try with each oven. So they still probably have 7 more to go. Hurrah, NASA!

Re:What were they thinking?

[Original Replica]

You don't want or need to deal with huge amounts of material to tell what compounds are in the soil.

You also don't want half of the contents to sublimate by leaving them exposed to sunlight and friction/heat from a vibrating screen. Considering how important it was to land where there was ice (polar landings are tough) you think they would be a bit more careful to preserve that ice since that is where they hoped to find the organic compounds.

Re:invalidate the tests

[profplump]

Why isn't "flawed data" at least sometimes the same as "some data" and therefore better than "no data"?

For example, what if you had a rain meter that leaked -- you couldn't accurately determine accumulation, and you couldn't conclusively ascertain that no water had fallen just because it was empty, but if the meter read 1.28" when you looked at it you could conclude that at least 1.28" of water had fallen since last time the collector was drained. The 1.28" reading would flawed, but the device would still provide the same sort of data it was designed to collect; so long as your understand the nature of the "flaw" in your data it is still generally useful.

Re:investment vs result

[Ihlosi]

its depressing how feeble and unreliable the space probe design are compared to the insane amounts of investment.

And you're ... qualified to make this statement ? Are you any kind of engineer (ME or something along those lines would be best) ?

shovel, to scoop up dirt, instead of some decent drilling apparatus that could get samples from much deeper and from harder surface.

Yes, of course, a drill. How brilliant. So where do you get all the power to run that drill ? How do you keep it lubricated ? How do you keep your lubricant from polluting your samples ? How do you move the drill around to drill in different places ? And remember, this is a space probe. Weight is at a premium.

solar panels that get covered in dust because someone is too lazy to add windscreen wipers.

So how well do your windshield wipers work when its completely dry ? How do you avoid scratching the surface of the solar panels (which will permanently degrade their output) ? What do you do when the wiper breaks down in the middle of its operation (which will knock out that solar panel completely) ?Also, now we've learned that Martian winds are strong enough to keep the panels clean.

making things heavier and more robust than needed resulting in insane liftoff prices.

Hey, you're the one suggesting adding all kinds of heavy (and useless) stuff to probes.

if businesses would be contracted to design and make happen space missions we would have 1000 men moon base by now.

If business were contracted to do so, we'd have a lot of dead people on the moon, a couple of businesses that have gone belly-up, and some shareholders and CEOs that got insanely rich in the process. Not sure if that's any better than what we have now.

you could just give the budget and say use what you must to accomplish it and the leftover is your profit.

Great, give me the money, here's your space probe. Business closes, owners and CEOs make off with wads of cash, space probe fails because they've been cutting a few corners too many. And don't even think of delaying payment until the probe was successful - no businessperson in their right mind would accept such a delay in payment.