Many of you have sent us great feedback about the hundreds of cool anaglyphs we just released. And they are fascinating to see! Several people have asked the next reasonable question, “Where are the DEMs?” A DEM, if you don’t already know, is a digital elevation model. This is a product that can also be produced from a HiRISE stereo pair. HiRISE DEMs are awesome because they can model the terrain at a resolution of 1 meter per post! That means for every square meter of Mars visible in a HiRISE image (for which we have stereo) we can derive an elevation value. This provides the opportunities to measure geological features, model hydrology and spacecraft traverses.

We would love to be able to release a DEM for every HiRISE stereo pair, but alas, they don’t exist yet! We here at HiROC and a few other groups have made some DEMs, but only a small percentage of all the acquired stereo has  been processed so far. Why?? Because creating a DEM is actually quite difficult, and requires specialized software and a fair amount of time.

But there is hope! So far, the USGS Astrogeology group has created several DEMs in support of the MSL landing site selection workshops, the Phoenix lander and the MER mission. They are available on the USGS website. Here is an example of one of their products:

Columbia Hills DEM

Soon, we will begin preparing the DEMs we have made for release to the PDS Imaging Node. So stay tuned…

Last week was the third landing site selection workshop for MSL, the Mars Science Laboratory. The workshop has been well covered in other blogs. If you’re unfamiliar with the seven sites up for consideration, the Martian Chronicles has posted excellent summaries of each site, starting with Miyamoto Crater and working through Gale Crater.

Most of the presentations from the workshop have also been posted here. It’s rare to see one without some HiRISE images!

Here at HiRISE, we are interested in this for several reasons – not only are some of our team members involved in the site selection, but HiRISE data have been integral to the process. HiRISE images have been used to study the small-scale geology of the sites, which is very powerful when combined with CRISM and other data sets to determine composition and mineralogy. HiRISE data has also provided calculations of the slopes and rock abundances around the landing sites, both of which are critical for the safety of the lander. We’ve been doing reconnaissance (the R in MRO!) of all of these sites since we started our primary mission! Here are some of the data we’ve produced for the MSL project.

• Lots of images! (links to a search for ‘MSL’ in our catalog; you can also search for the individual site names)
• Anaglyphs (red-blue 3-d of stereo pairs – these are so fun! )
• Digital Elevation Models (DEMs), which are painstakingly built from our stereo paired images. (This site doesn’t have any MSL DEMs posted yet, but they should be coming soon!)

I know people here have their favorites among these seven sites – what’s yours?