Layered Sediments in Hellas Planitia
Layered Sediments in Hellas Planitia
PSP_007820_1505  Science Theme: Glacial/Periglacial Processes
This image shows outcrops of light-toned layered rocks in the northern part of Hellas Planitia, the floor of a massive, ancient impact crater.

The floor of Hellas includes the lowest parts of the Martian surface, and has been proposed as the site of ancient lakes or seas.

The layers show some variations in color and brightness, alternating between light and dark material. The bright layers are extensively fractured into angular boulders and blocks, while the dark layers appear relatively smooth, although this could be due in part to sand or dust covering them. This alternation also appears to correspond to stairstep-like topography in places, suggesting that some layers are more resistant to erosion than others. However, in other areas, the slope is relatively constant.

Light-toned layered rocks are found in many sites on Mars, including much of the north rim of Hellas. They could have been deposited in many ways: volcanic ash, wind-blown sand, river or lake deposits. The occurrence of some of these around the edge of the deep floor of Hellas raises the possibility that these layers were deposited on the floor of an ancient lake, but other mechanisms are also possible.

Written by: Colin Dundas  (23 April 2008)

This is a stereo pair with PSP_009745_1505.
Acquisition date
27 March 2008

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
262.4 km (163.1 miles)

Original image scale range
26.3 cm/pixel (with 1 x 1 binning) so objects ~79 cm across are resolved

Map projected scale
25 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
50.8°, Northern Spring

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  46.9°
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   (1188MB)

IRB color
map-projected   (544MB)

Black and white
map-projected  (587MB)
non-map           (677MB)

IRB color
map projected  (246MB)
non-map           (536MB)

Merged IRB
map projected  (294MB)

Merged RGB
map-projected  (277MB)

RGB color
non map           (522MB)
Map-projected, reduced-resolution
Full resolution JP2 download
Anaglyph details page

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’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.