http://www.newscientistspace.com/article.ns?id=dn8397Mars Express is bringing home the science:
The first ever underground investigation of another planet has been performed by a radar antenna aboard Europe's Mars Express spacecraft. The instrument probed two kilometres below the Martian surface and found tantalising hints of liquid water pooling in a buried impact crater.
The MARSIS antenna was deployed successfully in June 2005 after a series of glitches. It works by sending radio pulses towards the Red Planet and then analysing the time delay and strength of the pulses that bounce back. The radio waves that penetrate the surface rebound when they encounter a sub-surface boundary between materials with different electrical properties - such as rock and water.
But aside from one Apollo 17 radar experiment on the Moon in 1972 - which yielded mixed results - the technique had never been tested.
The most exciting part of this experiment is simply "that it works", says MARSIS co-leader Jeff Plaut of NASA's Jet Propulsion Laboratory in Pasadena, California, US.
And here's the bit of unconfirmed data that has me all overreacting:
Intriguingly, the signal reflected from the bottom of the crater is so strong and appears so flat that it may be liquid water. "If you put water there, that's what the signal might look like," Johnson told New Scientist. But he cautions the data is based on only one pass over the region and could be caused by another material.
:bounce: