Posted on 06/07/2008 9:48:41 PM PDT by BenLurkin
Scientists ran into a snag when trying to deliver a sample of Martian arctic soil to one of the instruments on NASA's Phoenix Mars Lander, mission controllers said on Saturday.
The lander's robotic arm released a handful of clumpy Martian soil onto a screened opening of the Thermal and Evolved-Gas Analyzer (TEGA) on Friday, but the instrument did not confirm that any of the sample passed through the screen.
Images taken on Friday show soil resting on the screen over an open sample-delivery door of TEGA, which is designed to heat up soil samples and analyze the vapors they give off to determine the soil's composition.
The researchers have not yet determined why none of the sample appears to have gotten past the screen, but they have begun proposing possibilities.
"I think it's the cloddiness of the soil and not having enough fine granular material," said Ray Arvidson of Washington University in St. Louis, the digging czar for the $420 million Phoenix mission.
The Phoenix lander touched down on the red planet on May 25 to begin a planned three-month mission to hunt for buried water ice in the northern polar region of Mars. It is equipped with a scoop-tipped robotic arm, weather station, wet chemistry lab and eight ovens to study samples of Martian terrain and determine if the region could have once supported primitive life.
TEGA's screen is designed to let through particles up to 0.04 inch (1 millimeter) across while keeping out larger particles, in order to prevent clogging a funnel pathway to a tiny oven inside.
Mission scientists said they planned to send new commands to Phoenix to try to shake the sample into the oven as early as Monday. They'll spend Sunday developing the plan for the following Martian day.
The small vibration tool can shake the oven screen across a variety of frequencies, ranging from a light tapping to moderate shake, mission managers said.
"The soil that we're looking at is probably sandy and it has a lot of fine grains and dust, but it is also a little bit cohesive," Arvidson said. "I'm pretty confident that if we shake this stuff, we'll get some in."
For future samples, they may use the robotic arm to prepare a site by poking and prodding the Martian surface to break up clumps and clods. They may also collect smaller scoops of material to pour directly into the oven.
While this is the first oven they've tried to pour samples into, it is designated Oven 4 of eight. Despite the overflow of soil across the other oven doors, mission managers are confident the extra stuff won't hinder the opening of other instruments.
The TEGA ovens have an opening just 2 mm wide and are designed to collect about 30 milligrams of material for baking.
Phoenix's planned activities for Saturday include horizontally extending a trench, dubbed "Dodo," where the lander dug two practice scoops earlier this week, and taking additional images of a small pile of soil that was scooped up and dropped onto the surface during the second of those practice digs.
"We are hoping to learn more about the soil's physical properties at this site," Arvidson said. "It may be more cohesive than what we have seen at earlier Mars landing sites."
You're right; there is an important distinction between soil (a matrix formed by the action of weather and running water - and, here on Earth, also by biological mechanisms) and regolith (which is merely the pulverized remains of meteor impacts.)
I'd say that, since Mars has weather, it is legitimate to refer to the Martian surface as being covered by soil.
Regards,
Clay soil clumps together. That’s the problem
Maybe one-way? Inoperable cancer patient/volunteer?
Only if it has the right amount of moisture. So...
had also....making brick like clumps
They need to have the robot arm smack on the side a few times.
Hmm that’s true. I wonder if the water molecules chemically involve themselves in maintaining the bond, and thereby preventing their evaporation. I tried searching Wikipedia, but didn’t find anything on it.
They need to have the robot arm smack on the side a few times.
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The two fixes I see are that they could drive the lander around a bit to shake things (probably won’t work based on the surface photo’s I’ve seem and the speed of the crawler) or move the robot arm to it’s travel limits and let it bump into the “stops” to shake the lander ,,, (I am assuming they were stupid enough to build the screen device without a vibrating attachment or a tilt/dump function to jettison oversized/clogging debris.)
They’ve managed to get a mobile laboratory to Mars. I think they are doing a fantastic job.
OR it could be they particular piece of soil they decided to pick up is just too big to fit thru the screen.
The screen is necessary to get pieces small enough to work for their testing.
“(I am assuming they were stupid enough to build the screen device without a vibrating attachment or a tilt/dump function to jettison oversized/clogging debris.)”
Another story indicates they have the ability to shake the screen. They also have 7 different test units on board.
Lucky NASA...scooped up some marsian poop on first scoop.
It says right in the article:
Mission scientists said they planned to send new commands to Phoenix to try to shake the sample into the oven as early as Monday. They'll spend Sunday developing the plan for the following Martian day.
The small vibration tool can shake the oven screen across a variety of frequencies, ranging from a light tapping to moderate shake, mission managers said.
"...screen is designed to let through particles up to 0.04 inch (1 millimeter) across while keeping out larger particles..."
How many backhoe operators have 1 millimeter screens in their scoops?
The earthlings sure embarass real extraterrestrial probe designers.
I have images of shrink wrap left on the opening of the screen to keep out dust (prior to liftoff from Earth). Sort of like the plastic coverings sometimes left on notebook computers during shipping.
I understand that both Tonka and Hot Wheels are working on it.
"Some army personnel in Vietnam is perplexed at what they found at the site. There is no clear evidence of any explosion. Metallic parts they found is that of era of US-Vietnam war and has nothing to do with this UFO mid air explosion.
Biochemical UFOs do not leave trace of any nature. Because of their nature and power to bio-disinegrate fast, they do not leave any trace. They travel through wormholes bending space and time. They go across universes through the Hyperspace. They can defy the basic laws of quantum physics. They are propelled by gravity waves. They have the stealth of electromagnetic flux. They are navigated and controlled from parallel universes."
What would an excavator know about digging dirt? Do they have PhDs?
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