Phobos in UV


phobos-in-uvThis is the Martian moon Phobos as observed by the MAVEN spacecraft’s Imaging Ultraviolet Spectrograph. Orange shows mid-ultraviolet (MUV) sunlight reflected from the surface of Phobos. Blue shows far ultraviolet light which is scattered off of hydrogen gas in the extended upper atmosphere of Mars. Phobos blocks the background far UV light, eclipsing the ultraviolet sky. Comparing MAVEN’s images and spectra of the surface of Phobos to similar data from asteroids and meteorites may provide clues to the moon’s origin–whether it is a captured asteroid or was formed in orbit around Mars. The MAVEN data will also help scientists look for organic molecules on the surface of Phobos. Evidence for such molecules has been reported by previous measurements from the ultraviolet spectrograph on the Mars Express spacecraft.

Image Credits: CU/LASP and NASA

Clouds on Mars


Images from MAVEN’s Imaging UltraViolet Spectrograph were used to make this movie of rapid cloud formation on Mars. The ultraviolet light reflected from the planet has been rendered in false color to show what might be seen with ultraviolet-sensitive eyes. The movie uses four MAVEN images to show about 7 hours of Mars rotation, and it interleaves simulated views that could have been seen between the four images. The length of the Martian day is similar to Earth’s, so the movie shows just over a quarter day. The left part of the planet is in morning and the right side in afternoon. Mars’ prominent volcanoes, topped with white clouds, can be seen moving across the disk.  Olympus Mons, the tallest in the Solar System, appears as a prominent dark region near the top with a small white cloud at the summit that grows during the day. Olympus Mons appears dark because the volcano rises up above much of the hazy atmosphere. Three more volcanoes appear in a diagonal row with their cloud cover merging to span a thousand miles by the end of the “day.”

Video Credit: NASA