Astronomy Now Home
Home Magazine Resources Store

On Sale Now!

The October 2014 issue of Astronomy Now is on sale! Order direct from our store (free 1st class post & to UK addresses). Astronomy Now is the only astronomy magazine specially designed to be read on tablets and phones. Download the app from Google Play Store or the Apple App Store.

Top Stories

Earthshine used to test life detection method
...By imagining the Earth as an exoplanet, scientists observing our planet's reflected light on the Moon with ESO's Very Large Telescope have demonstrated a way to detect life on other worlds...

Solid buckyballs discovered in space
...Astronomers using NASA’s Spitzer Space Telescope have detected a particular type of molecule, given the nickname “buckyball”, in a solid form for the first time...

Steamy water-world gets the Hubble treatment
...Hubble Space Telescope observations of a 7 Earth-mass planet find an unusual water-rich world swathed in a thick, steamy atmosphere...

Mars Reconnaissance Orbiter maps out hidden ice
by Ian Randall
Posted: 5 March 2010

Bookmark and Share

Significant volumes of buried ice have been discovered in the mid-latitudes of Mars’ northern hemisphere, according to a report presented at the 41st Lunar and Planetary Science Conference earlier this week.

Subsurface ice was first discovered by the Mars Reconnaissance Orbiter two years ago. Two hundred and fifty separate observations of the study region, which is around the size of California, have been made by the orbiter using the craft’s Shallow Radar instrument. Study of the data has revealed that hidden ice appears to be quite a common phenomenon.

The Shallow Radar instrument on NASA's Mars Reconnaissance Orbiter has detected widespread deposits of glacial ice in the mid-latitudes of Mars. Image: NASA/JPL-Caltech/ASI/University of Rome/Southwest Research Institute.

“We have mapped the whole area with a high density of coverage. These are not isolated features. In this area, the radar is detecting thick subsurface ice in many locations,” says Jeffrey Plaut, of NASA’s Jet Propulsion Laboratory.

The ice, which makes up a large proportion of the non-polar ice on the red planet, was seen to be most common around the bottom of cliffs and slopes, or found trapped in craters and other such valleys.

In the rough terrain of Deuteronilus Mensae, a region of Mars which lies halfway between the equator and the low plains of the pole to the north, the underground ice deposits can be seen reaching out for hundreds of kilometres. Plaut and his colleagues have drawn up a map of the confirmed ice deposits, which was presented at the conference, held in The Woodlands, Texas, across this week.

It is now possible to advance theories as to the origin of this ice, and it is believed that the deposits may have been emplaced by the retreat of regional ice sheets.

Illustration of the Mars Reconnaissance Orbiter's Shallow Radar device in action. Image: NASA.

“The hypothesis is the whole area was covered with an ice sheet during a different climate period, and when the climate dried out, these deposits remained only where they had been covered by a layer of debris protecting the ice from the atmosphere,” Plaut says.

The Shallow Radar instrument, or SHARAD for short, uses a frequency varying subsurface sounding radar to enable high resolution imaging of the top kilometre of Mars surface. SHARAD, which has been in operation over Mars for three years, was developed by the Italian Space Agency, in conjunction with California’s Astro Aerospace, who developed the antenna.

The next immediate step in the research will be to continue increasing the extent of the mapped region – but with the possibility of this ice containing environmental footprints from its time of deposition, it seems quite possible that these hidden treasures might be targeted for extraction and study by future space missions.

The Planets
From tiny Mercury to distant Neptune and Pluto, The Planets profiles each of the Solar System's members in depth, featuring the latest imagery from space missions. The tallest mountains, the deepest canyons, the strongest winds, raging atmospheric storms, terrain studded with craters and vast worlds of ice are just some of the sights you'll see on this 100-page tour of the planets.

Hubble Reborn
Hubble Reborn takes the reader on a journey through the Universe with spectacular full-colour pictures of galaxies, nebulae, planets and stars as seen through Hubble's eyes, along the way telling the dramatic story of the space telescope, including interviews with key scientists and astronauts.

3D Universe
Witness the most awesome sights of the Universe as they were meant to be seen in this 100-page extravaganza of planets, galaxies and star-scapes, all in 3D!


© 2014 Pole Star Publications Ltd.