Wednesday, May 16, 2012

More on Vesta and HED Meteorites

The above image shows three slices of HED-class meteorites. Image Credit: University of Tennessee

This is a follow-up to the recent paper by the NASA Dawn mission team regarding asteroid Vesta and its parentage of the HED family of meteorites. Back on May 11th, a paper by the mission team was posted in the journal Science. In the paper, the team presented evidence that the family of meteorites known as howardite, eucrite and diogenite (HED) originated on asteroid 4 Vesta, and likely left Vesta as a result of the impact which created the large basin near Vesta's south pole.

Above are three nifty slices of HED-class meteorites. They were viewed through a polarizing microscope, where different minerals appear in different colors. The texture of the rocks reveals that they crystallized at different rates. The image on the left comes from a meteorite named QUE 97053 (Antarctica), which is basaltic eucrite. The image in the middle comes from the Moore County (North Carolina) cumulate eucrite. The image on the right comes from a diogenite meteorite named GRA 98108 (Antarctica).

Launched in 2007, NASA's Dawn spacecraft has been studying Vesta since its arrival in July of 2011. The Dawn spacecraft will depart Vesta on August 26 (my birthday) . At that time it will head for its next study target, the dwarf planet Ceres, arriving in 2015.

And now, the mission particulars...

Dawn's mission to Vesta and Ceres is managed by JPL for NASA's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program managed by NASA's Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. in Dulles, Va., designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. The California Institute of Technology in Pasadena manages JPL for NASA.

For more information about the Dawn mission, visit: and .

To read more about the Vesta discoveries, check out the online home page of the journal Science:


No comments: