Google+ Mars Travel: Gypsum on Mars
Showing posts with label Gypsum on Mars. Show all posts
Showing posts with label Gypsum on Mars. Show all posts

Mars Photo of the Day - Jan 20 2012

Today's Image of Mars is a north-looking perspective view of Juventae Chasma, a large fissure that cuts 5000m into Lunae Planum on Mars and measures 180km east-west and 250km north-south.
Juventae Chasma obvious interaction with water led NASA to consider it as a candidate destination for Mars Science Laboratory Curiosity. Though it was not selected to be the MSL landing spot, there is still much to be learned from the chasm.

Scientists believe that sometime 3-4 billion years ago Juventae Chasma was filled with water, which then created the large deposits of clays, gypsum, and other sulfate minerals we see today. They have speculated that Juventae once had a habitat that was suitable to life, which keeps it on the list of potential landing sites for future missions to Mars

How did Juventae Chasma form?

Scientists speculate that Juventae Chasm formed as a result of faulting and volcanic heat opening up cracks in the surface, which then let water and subsurface ice out, causing the surface to collapse from the floods that resulted. There was enough water that it poured out of the northern end and created the outflow channel, Maja Valles, which flows all the way to the Chryse impact basin.

Eventually Juventae Chasma stopped growing, but the water within the canyon altered the rocks and surface materials, turning them into the gypsum and other aqueous material we see today.

The ridge you see in the northeast of Juventae Chasma's valley measures 59km long, 23km wide, and 2500m high, making it half as high as the chasm's walls.. This mountain became of interest to scientists when they determined that it was composed of sulfate deposits.

On the top part of the ridge, Mars Express' OMEGA instrument detected gypsum, with 12 distinct layers present. Below the gypsum layers lies kieserite, a form of magnesium sulfate. Both gypsum and kieserite are classified as evaporates, meaning that they often form where lakes of salty water dry up. 

The potential landing site for future missions to Mars lies on the southern tip of this ridge. Any rover would then likely move along the western side of the ridge where there are numerous layered deposits that could provide answers as to whether Mars ever sustained life. 

This image was taken by the High Resolution Stereo Camera (HRSC) aboard Mars Express. Clicking on the image will take you to the original high resolution image from them.


Mars Photo of the Day - Dec 13 2011

Today's Image of Mars is of Hebes Chasma, an enclosed trough located in the most northern part of Valles Marineris that measures nearly 8000m deep. In the center of Hebes Chasma is an 8000m high mesa (flat topped mountain) with many layered deposits. It almost rises to the same height as the terrain surrounding Hebes Chasma.

Measurements from the OMEGA spectrometer on Mars Express have shown water bearing minerals, like gypsum, in Hebes Chasma, evidence that there was once an abundance of water in the trough.

It is thought that Hebes Chasma formed because of enormous stress in the Martian crust, which resulted in a number of radial faults. This stress was likely caused by crustal uplift from the development of many volcanoes in the nearby Tharsis region.

You really need to click on this image so you can see the high resolution image from the ESA. [See their article on this image and others like it]



Mars Photo of the Day - Dec 7 2011

Today's Image of Mars is another view of Homestake, the vein recently examined by Mars Exploration Rover Opportunity on Mars. Today NASA announced that Homestake appears to be Gypsum or another form of calcium sulfate. This is further evidence that water once flowed on The Red Planet.

This photo links to the original full size image from MER Opportunity
Source: NASA/JPL/MER

To understand how NASA came to this conclusion I have taken an excerpt from their article on the matter.
The Homestake deposit, whether gypsum or another form of calcium sulfate, likely formed from water dissolving calcium out of volcanic rocks. The calcium combined with sulfur that was either leached from the rocks or introduced as volcanic gas, and it was deposited as calcium sulfate into an underground fracture that later became exposed at the surface.
The Mars Rover's Spirit and Opportunity have found evidence of water on Mars before, so what makes Homestake so special?

Homestake is more highly concentrated Calcium Sulfate than any previously examined on Mars, which leads scientists to believe that it may have been deposited by water that was less acidic than indicated in previous areas Opportunity has examined. Water that is closer to neutral would be more hospitable to life as we know it.

For more on Homestake I recommend you read the official NASA news release on the matter.