A Glimpse into History
A Glimpse into History
ESP_046851_2040  Science Theme: Landscape Evolution
Nothing gets a geologist more excited than layered bedrock, except perhaps finding a fossil or holding a meteorite in your hand. All of these things create a profound feeling of history, the sense of a story that took place ages ago, long before we came appeared. Layered bedrock in particular tells a story that was set out chapter by chapter as each new layer was deposited on top of older, previously deposited layers.

Here in Nili Fossae, we see layered bedrock as horizontal striations in the light toned sediments in the floor of a canyon near Syrtis Major. (Note: illumination is from the top of the picture) The ancient layered rocks appear in pale whitish and bluish tones. They are partially covered by much younger ripples made up of dust and other wind blown sediments. The rock of the nearby canyon wall is severely fractured and appears to have shed sand and rocks and boulders onto the floor. This canyon did not form by fluvial erosion: it is part of a system of faults that formed a series of graben like this one, but water probably flowed through Nili Fossae in the distant past.

Orbital spectral measurements by the OMEGA instrument on Mars Express and CRISM on MRO detected an abundance of clay minerals of different types in the layered sediments inside Nili Fossae, along with other minerals that are typical of sediments that were deposited by water. The various colors and tones of the layered rocks record changes in the composition of the sediments, details that can tell us about changes in the Martian environment eons ago. Nili Fossae is a candidate site for a future landed robotic mission that could traverse across these layers and make measurements that could be used to unravel a part of the early history of Mars. Nili Fossae is a history book that is waiting to be read.

Written by: Paul Geissler  (9 November 2016)
Acquisition date
25 July 2016

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
282.5 km (175.6 miles)

Original image scale range
57.1 cm/pixel (with 2 x 2 binning) so objects ~171 cm across are resolved

Map projected scale
50 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
56°, with the Sun about 34° above the horizon

Solar longitude
191.7°, Northern Autumn

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  342.1°
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   (297MB)

IRB color
map-projected   (175MB)

Black and white
map-projected  (161MB)
non-map           (144MB)

IRB color
map projected  (69MB)
non-map           (151MB)

Merged IRB
map projected  (272MB)

Merged RGB
map-projected  (269MB)

RGB color
non map           (140MB)

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.