slideshow 1 slideshow 2 slideshow 3 slideshow 4 slideshow 5 slideshow 6

3-D Analysis Offers New Info On Martian Climate Change, Age of Polar Caps

 

than one

Three-dimensional (3-D) subsurface radar volumes generated from thousands of 2-D radar profiles are revealing new information about the polar regions of Mars, including more accurate mapping of CO2 and water ices, the discovery of buried impact craters, and new elevation data. PSI Senior Scientist Nathaniel E. Putzig is the lead author of the Icarus paper “Three-dimensional radar imaging of structures and craters in the Martian polar caps.”  PSI’s Isaac B. Smith is a co-author. 

This information will help scientists better understand Martian climate changes and may allow them to determine the age of the polar caps without using climate models. The 3-D data volumes were assembled from observations by the Shallow Radar (SHARAD) sounder onboard NASA’s Mars Reconnaissance Orbiter (MRO) during more than 2,000 passes over each Martian pole. 

“An example is the more accurate mapping of the CO2 ice deposits in the south that allows us to provide a new, larger estimate of their volume. Sublimation of that CO2 ice into the atmosphere – which is thought to have occurred at various times in Martian history – would more than double the current atmospheric pressure,” said Putzig. “That in turn would allow liquid water to be stable at the surface in many more locations than it is today.”

Above, cut-away perspective view (toward 150°E) into the depth-converted Planum Boreum SHARAD 3-D volume, showing radar-return power (blue high, white low) from previously known (black) and buried (red) features within the north polar cap. The SHARAD no-data zone is due to MRO’s orbit inclination. Depth conversion assumes pure water ice (εʹ = 3.15). Scale is approximate (varies in this perspective), with vertical exaggeration of 136:1. 

Below, Cut-away perspective view (toward 315°E) into the depth-converted Planum Australe SHARAD 3-D volume, showing radar-return power (blue high, white low) from previously known (black) and buried (red) features within the south polar cap. The SHARAD no-data zone is due to MRO’s orbit inclination. Depth conversion assumes pure water ice (εʹ = 3.15). Scale is approximate (varies in this perspective), with vertical exaggeration of 136:1.

Credit: Putzig et al.

than below

Below, a video depiction of the MRO passing over the Martian polar regions:

Credit: PSI / D. Hornisher

Nov. 20, 2017

PSI, a Nonprofit Corporation 501(c)(3), and an Equal Opportunity/M/F/Vet/Disabled/Affirmative Action Employer.
Corporate Headquarters: 1700 East Fort Lowell, Suite 106 * Tucson, AZ 85719-2395 * 520-622-6300 * FAX: 520-622-8060
Copyright © 2017 . All Rights Reserved.