Wednesday, June 13, 2012

Mars: Analyzing Layers of History

Gale Crater Landing Site - Mars
On August 5, 2012, NASA hopes to land the most robust rover ever, the Mars Science Laboratory (MSL), nicknamed Curiosity, inside the ellipse drawn on the graphic to the left (click to enlarge).

 The graphic detail is of Gale Crater, on the planet Mars.

The mountain inside the crater was not likely formed by the meteorite impact billions of years ago, rather it was more likely formed later by layered deposits over eons of time, most likely when water covered both the crater as well as the area around the crater.

Gale Crater - Overhead View
The graphic photo to the right (click to enlarge) is another view of the crater, also containing the ellipse shaped landing zone (at about 11 o'clock just inside the crater rim).

That landing zone has been shrunk to a much smaller target area recently, because the landing software has been improved, tested, and uploaded to Curiosity.

This photo clearly shows that the mountain area that will be studied is not in the center of the crater.

After the MSL Curiosity lands safely, is checked out, then begins its journey, it will eventually try to follow canyons uphill toward the top of the mountain.

Along the way up the mountain, it will sample layers of deposited material, analyzing them for both their mineral content, as well as indications of how those minerals were deposited.

The scientists conducting the analysis will be able to determine if the material was laid down in water, the salinity and acidity of that water at the time, as well as general environmental conditions that changed the layers over vast amounts of time.

Furthermore, the clay materials near the lowest elevations will be analyzed for organic materials as well as signatures of microbial or other life forms:
"This may be one of the thickest exposed sections of layered sedimentary rocks in the solar system. The rock record preserved in those layers holds stories that are billions of years old -- stories about whether, when, and for how long Mars might have been habitable."
(Strange Attraction ... Gale Crater). One of the main interests Dredd Blog has is the source of the microbial fossils found in meteorites that originated on Mars but later crashed into the Earth.

Some of them have been analyzed by NASA scientists who have concluded that the fossils inside those meteorites are organic, microbial life, which came from Mars.

That is a controversial issue at this time, however, there is a chance that the Curiosity rover will be able to add to the data upon which the controversy is based.

Another controversial issue is the Exploded Planet Hypothesis which says that a planet located between Mars and Jupiter exploded.

It generated meteors which led to cratering on other planets and moons when those meteors became meteorites.

When that planet exploded it left asteroids and comets as residue and debris.

Anyway, the analysis of strata layers on Mars, when compared to eventual analysis of strata layers on Phobos and on the asteroid Vesta, may provide some sort of syncronization that could help to solve these controversial issues.

The following video features the lead geologist of the Curiosity rover exploration program, who explains how the site was chosen, and what they expect to find there.


LOG of video:

0:00:00 Introduction of Dr. Golombek
0:02:10 Dr. Golombek begins
0:04:30 Dry Lakebed on Mars
0:04:50 ~4.5 bn yr old lake
0:05:10 oldest Earth life ~3.9 bn yrs old
0:06:00 rock suggests Earth life may have originated on Mars
0:07:30 water was on surface of mars ~3.8 bn years ago (Burns Formation)
0:09:30 lots of clay across Martian surface indicates liquid, neutral water
0:10:15 about Curiosity rover
0:10:40 minerals in rocks identify how rock formed, and its environment
0:12:00 how Curiosity landing takes place on Mars; needed surface conditions
0:16:00 protecting Mars from Earth "contamination" by rover
0:17:00 how landing site was chosen
0:19:00 final 4 sites / reduced to one eventually
0:23:00 focus on Gale Crater during selection process
0:23:30 landing site near 5 km mound (clay, sulfates,in a layered stack)
0:31:30 sand dunes at edge of landing area have ways to go through them
0:33:20 routes up the mound to clay layer past first "fence"
0:33:40 sulfate layers also accessible past second "fence"
0:34:20 mound canyons probably more difficult but doable
0:37:00 what is Gale landing and mound site going to be like
0:38:00 landing site dusty like Gusev (Spirit rover), mound will be less dusty
0:38:50 bedrock layers are exposed at base of mound, top is very fine dust
0:40:00 landing site has a dry river delta
0:40:50 recent craters at site may have uncovered organic material
0:41:50 simulation of what mound looks like
0:42:40 landing August 5, 2012 ~10:30 pm Pacific Time
0:42:50 could take months to a year to reach the mound from landing site
0:43:15 question session
1:03:03 END

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