Mars Exploration Rovers (MERs)

http://marsrovers.jpl.nasa.gov/

Strategy: “Follow the Water”

MER-B “opportunity” before launch. Usually spacecraft are given “letter” designations prior to paunch, and “number” designations afterwards.

Criteria: Geomorphology: signs of past running water

Chemical: hemataite, carbonates, sulfates

MER-A “Spirit” was targeted for Gusev crater, due to the abundant evidence of water having been present from the geologic structures there. Press release images here: http://marsrovers.jpl.nasa.gov/gallery/press/spirit/

MER-B “Opportunity” was sent to Meridiani Planum as that’s where the hematite was. Press release images here:

http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/


Entry	Descent

Landing	Rolling out

Unlike previous missions, the MERs sent back images during their descent this view is from an altitude of 1400m. This enabled ground controllers to minimize the lateral velocity of the package, to improve its survival until impact. This image was taken by Spirit at an altitude of 1400 m.

The MGS was able to image the landing sites, so that scientists would know exactly where they were. This series of images shows Opportunity resting inside a small crater a cosmic “hole in one”!

3D image of Opportunity site, showing rock outcrops:

Close up of one section of this image:

The MERs carried a “Mini-TES”. This is a spectra image of the scene from Opportunity. Red indicates high concentration of hematite.

Reflectance spectra of dirt particles

An example of a match between laboratory spectrum of hematite and some of the material on the surface of Mars at the location of Opportunity.

CREATOR: XV Version 3.10a Rev: 12/29/94 (PNG patch 1.2) Quality = 100, Smoothing = 0

	At the Opportunity site were numerous little spheres, dubbed “blueberries”


		Reflectance spectra: Blueberries are hematite!

Now the big question was this: is the hematite due to aqueous or volcanic origin. Spectral analysis indicated the presence of a lot of olivine…

Not good! For in the presence of water, olivine would be converter into carbonate rock! If there is a lot of olivine, water could not have been present for extended periods of time!