Look out below! March 4, 2008Posted by astroed in : Astronomy, Education , trackback
We often think of the Universe as unchanging, with celestial bodies not appearing to change much over human lifetimes. Sometimes though we see an image that dramatically reminds us that in reality it is a dynamic place. I came across one such image today that literally took my breath away.
The HiRISE camera orbiting Mars captured this stunning image of a series of avalanches on the North Polar scarps.
Caught in Action: Avalanches on North Polar Scarps (PSP_007338_2640)
Credit: NASA/JPL/University of Arizona
This cliff is over 700m tall with a 60 degree slope. The white material at left is solid carbon dioxide, ‘dry ice’, sublimating into gas as the Martian spring develops. As HiRISE has already taken images of this site prior to the avalanche geologists and planetary scientists have a wonderful opportunity to examine the before and after effects of an avalanche on another world. The high-resolution imagery and massive dataset from HiRISE provides them with the best orbital imagery yet for a Solar System object other than our Earth. I was fortunate to visit the LPL at the University of Arizona, Tucson, a couple of years ago and see a mockup of the HiRISE orbiter and see simulations of the imagery that the team hoped to obtain with it so it is great to see the actual orbiter sending back such a wealth of imagery.
This image has already excited people around the world with the phones running hot at the Canberra Deep Space Communication Centre at Tidbinbilla and similar sites. Bad Astronomy and CosmicVariance both have it on their blogs too.