Wednesday, May 5, 2010

The Frozen Dunes of Mars Revisited

Posted By on Wed, May 5, 2010 at 10:46 PM

ESP_017043_2640.jpg
  • NASA/JPL/University of Arizona

The UA Lunar and Planetary Lab has released a particularly beautiful new batch of HiRISE photos of the Martian surface this week. See them here.

Don't forget: The LPL is having a picnic on Mount Lemmon on Saturday, May 22. Details on how to make your reservations before the May 14 deadline here.

HiRISE team member Ken Herkenhoff tells us about the photograph:

Like Earth, Mars has seasonal polar caps that grow in the winter and retreat in the spring, but on Mars the seasonal caps are composed primarily of carbon dioxide (dry ice). Carbon dioxide is the major component of the Martian atmosphere, and a significant fraction

of the mass of the atmosphere is cycled through the seasonal caps every year.

This image shows sand dunes that are mostly covered by seasonal frost/ice in the northern spring. When the springtime sun shines on the ice, some of it penetrates to the base of the ice and warms the dark sand dune surface below. The warm sand evaporates the carbon dioxide ice from below, building gas pressure that apparently breaks the ice and carries sand to the surface as the pressure is released. The sand then cascades down the surface of the ice, forming the streaks seen in this image.

Comments

Subscribe to this thread:

Add a comment

Previously in the Range

More by Jim Nintzel

Today | Mon | Tue | Wed | Thu | Fri | Sat
DO(OM) Yoga

DO(OM) Yoga @ Floor Polish

Sundays, 8-9 p.m.

All of today's events | Staff Picks

Staff Pick

A Christmas Carol & Dickens Festival

A Southern Arizona holiday tradition. This celebrated musical theatre production of the timeless classic captivates audiences with… More

@ Berger Performing Arts Center Fridays-Sundays, 7-10 p.m. Continues through Dec. 16 1200 W. Speedway Blvd.

» More Picks

Submit an Event Listing

Popular Content

  1. In The Flesh: The Juilliard String Quartet Bears Gifts (The Range: The Tucson Weekly's Daily Dispatch)
  2. 21 Great Things to Do in Tucson This Weekend: Dec. 14-16 (The Range: The Tucson Weekly's Daily Dispatch)
  3. The Age of Online Shopping Could Mark the Beginning of "Retail Apocalypse" (The Range: The Tucson Weekly's Daily Dispatch)
  4. TUSD Rejects Freedom Center's High School Course (The Range: The Tucson Weekly's Daily Dispatch)
  5. Three and Out: Uncle Herm and the ASU Sun Devils Come to Tucson (The Range: The Tucson Weekly's Daily Dispatch)

© 2018 Tucson Weekly | 7225 Mona Lisa Rd. Ste. 125, Tucson AZ 85741 | (520) 797-4384 | Powered by Foundation