The Coming and Going of Ice
The Coming and Going of Ice
ESP_042440_1380  Science Theme: 
Like Earth’s water table, Mars has an ice table. Sometimes, the ice table coincides with the ground’s surface as it does here. The knobby, pitted terrain is caused when ice is deposited and then sublimates over and over again. This geologic process is called “accrescence” and “decrescence” and also occurs on Neptune’s moon Triton and on Pluto, though in the outer Solar System the ice is not water ice.

Other evidence for ice here includes the rope-like, curved flow feature that resembles glacial flow.

Solis Planum—a huge mound south of Valles Marineris—is the location of this image.

Written by: Kirby Runyon (audio: Tre Gibbs)  (9 December 2015)
Acquisition date
16 August 2015

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
246.2 km (153.0 miles)

Original image scale range
49.7 cm/pixel (with 2 x 2 binning) so objects ~149 cm across are resolved

Map projected scale
50 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
66°, with the Sun about 24° above the horizon

Solar longitude
28.2°, Northern Spring

For non-map projected images
North azimuth:  96°
Sub-solar azimuth:  50.2°
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

Black and white
map-projected   (187MB)

IRB color
map-projected   (113MB)

Black and white
map-projected  (94MB)
non-map           (101MB)

IRB color
map projected  (38MB)
non-map           (116MB)

Merged IRB
map projected  (175MB)

Merged RGB
map-projected  (162MB)

RGB color
non map           (109MB)
B&W label
Color label
Merged IRB label
Merged RGB label
EDR products

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

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/University of Arizona

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.