New study may help identify areas with and without accessible water ice on Mars

September 26, 2017 by Alison Mitchell, NASA
Much of the plains of Meridiani Planum as seen by the Opportunity rover are flat, featureless, and covered by sand dunes. Credit: NASA/JPL/Cornell

New findings reveal deposits on Mars that could be interpreted to be ice-rich may contain little or no ice at all, based on an analysis of radar sounder data for Meridiani Planum—an area on the planet's equator being explored by the Opportunity rover.

This new insight into Meridiani Planum may help identify areas with and without accessible , a resource critical to future human exploration and possible colonization of Mars. A new paper detailing the findings is published in Geophysical Research Letters, a journal of the American Geophysical Union.

In the new study, researchers present new compaction models for materials on Mars that suggest the electrical properties of the deposits of Meridiani Planum, derived from data collected by the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument, can be explained without the need for pore-filling ice.

The MARSIS instrument transmits low-frequency radio pulses that penetrate certain geologic materials and are reflected back where the radio pulses encounter a change in bulk density or composition of the materials. The detection of subsurface reflectors can be used to determine the dielectric constant, a key of the materials, by measuring the travel time delays between radar pulses reflected by the surface and subsurface interfaces in Meridiani Planum.

The plains of Meridiani Planum are located along the equator in the heavy cratered terrain of Arabia Terra. Meridiani Planum covers an area of approximately 77,000 square kilometers (about 47,800 square miles) or approximately the size of South Carolina. Credit: NASA/JPL/Smithsonian

This analysis indicates that the deposits of Meridiani Planum have a relatively low dielectric constant. Pure water ice has a low dielectric constant and deposits on Mars with low dielectric constants are often interpreted to be ice-rich.

However, newly derived compaction models for Mars indicate that the derived, relatively low dielectric constant of the Meridiani Planum deposits are consistent with a thick sequence of ice-free, porous, windblown sand. Unlike other geologic that have been suggested for Meridiani Planum such as volcanic ash or silicate dust, a thick deposit of sand-sized particles on Mars does not compact nearly as much.  

 "It's very revealing that the low dielectric constant of the Meridiani Planum deposits can be explained without invoking pore-filling ice," said Thomas R. Watters, a planetary scientist in the Center for Earth and Planetary Studies at the National Air and Space Museum in Washington, D.C. and lead author of the new study. "Our results suggest that caution should be exercised in attributing non-polar deposits on Mars with low constants to the presence of water ice."

Explore further: Hematite-rich deposits in Capri Chasma

More information: Thomas R. Watters et al. Radar sounder evidence of thick, porous sediments in Meridiani Planum and implications for ice-filled deposits on Mars, Geophysical Research Letters (2017). DOI: 10.1002/2017GL074431

Related Stories

Hematite-rich deposits in Capri Chasma

December 22, 2016

Capri Chasma is located in the eastern portion of the Valles Marineris canyon system on Mars, the largest known canyon system in the Solar System. Deeply incised canyons such as this are excellent targets for studying the ...

Volcanic ash in Meridiani Planum

May 12, 2010

Deposits of volcanic ash colour this view of the Meridiani Planum, as seen by the Mars Express High Resolution Stereo Camera. They also give clues to the prevailing wind direction in this region of Mars.

Mars region probably less watery than thought

December 21, 2005

A region of Mars that some planetary scientists believe was once a shallow lakebed and likely habitable for life may not have been so wet after all, according to a new University of Colorado at Boulder study.

Spotlight on Schiaparelli's landing site

August 11, 2016

Schiaparelli, the Entry, Descent and Landing Demonstrator Module of the joint ESA/Roscosmos ExoMars 2016 mission, will target the Meridiani Planum region for its October landing, as seen in this mosaic created from Mars Express ...

Image: Jarosite in the Noctis Labyrinthus Region of Mars

February 22, 2016

This image, acquired on Nov. 24, 2015 by the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter, shows the western side of an elongated pit depression in the eastern Noctis ...

Recommended for you

Video: Net successfully snares space debris

September 19, 2018

The RemoveDEBRIS satellite has successfully used its on-board net technology in orbit – the first demonstration in human history of active debris removal (ADR) technology.

Mercury studies reveal an intriguing target for BepiColombo

September 19, 2018

A month before the planned launch of the joint ESA-JAXA BepiColombo mission to Mercury, two new studies shed light on when the innermost planet formed and the puzzle of its chemical composition. The findings will be presented ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.