Spring Slide
NASA/JPL/UArizona
Spring Slide
ESP_033433_2650  Science Theme: Climate Change
The north polar region of Mars is capped with layers of water ice and dust, called the “polar layered deposits.” This permanent polar cap is covered in the winter with a layer of seasonal carbon dioxide ice.

When the sun rises in the spring, the steep edges of the polar layered deposits are the first to warm up. The dry ice sublimes (going directly from a solid to a gas) and destabilizes loose chunks perched on the steep cliff. Material from the weaker layers gets dislodged and cascades down the steep slope.

Here, we can see a dark streak marking the path of that loose material, approximately 1 kilometer wide. HiRISE images often show avalanches in progress in the springtime along the edge of the polar layered deposits in this area.

Written by: Candy Hansen (audio by Phil Plait)  (30 October 2013)
 
Acquisition date
13 September 2013

Local Mars time
12:41

Latitude (centered)
85.061°

Longitude (East)
239.038°

Spacecraft altitude
317.8 km (197.5 miles)

Original image scale range
63.8 cm/pixel (with 2 x 2 binning) so objects ~191 cm across are resolved

Map projected scale
50 cm/pixel

Map projection
Polarstereographic

Emission angle
4.7°

Phase angle
73.4°

Solar incidence angle
76°, with the Sun about 14° above the horizon

Solar longitude
21.3°, Northern Spring

For non-map projected images
North azimuth:  119°
Sub-solar azimuth:  308.8°
JPEG
Black and white
map projected  non-map

IRB color
map projected  non-map

Merged IRB
map projected

Merged RGB
map projected

RGB color
non-map projected

JP2
Black and white
map-projected   (389MB)

IRB color
map-projected   (219MB)

JP2 EXTRAS
Black and white
map-projected  (175MB)
non-map           (167MB)

IRB color
map projected  (59MB)
non-map           (178MB)

Merged IRB
map projected  (389MB)

Merged RGB
map-projected  (338MB)

RGB color
non map           (159MB)
ADDITIONAL INFORMATION
B&W label
Color label
Merged IRB label
Merged RGB label
EDR products
HiView

NB
IRB: infrared-red-blue
RGB: red-green-blue
About color products (PDF)

Black & white is 5 km across; enhanced color about 1 km
For scale, use JPEG/JP2 black & white map-projected images

USAGE POLICY
All of the images produced by HiRISE and accessible on this site are within the public domain: there are no restrictions on their usage by anyone in the public, including news or science organizations. We do ask for a credit line where possible:
NASA/JPL/UArizona

POSTSCRIPT
NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA’s Science Mission Directorate, Washington. The HiRISE camera was built by Ball Aerospace and Technology Corporation and is operated by the University of Arizona.