Paris, 25 Feb 2005
These images, taken by the High Resolution Stereo Camera (HRSC) on board ESA's Mars Express spacecraft, were released at the First Mars Express Science Conference this week. They show the areas of focused research - water, ice, glaciers and volcanism.
Echus Chasma is the source region of the Kasei Valles channel. This perspective image was taken by Mars Express during orbit 97. It shows that liquid water was present on the surface of Mars thousands of millions of years ago.
Gigantic waterfalls poured over the 4000-metre high cliffs, and fed a lake in the valley. Later, when the planet became cooler, the lakes froze and glaciers formed, carving the giant Kasei Valles. These perspective views of the western side of the Olympus Mons caldera show evidence of ice/snow and water. The close-up image (right) shows detail in the left side of the scarp above.
On the eastern side of the giant volcano, lava produced between 200 million and 20 million years ago melted a snow and ice layer on the volcanic shield, with the result that liquid water was on the surface as recently as 20 million years ago.
On the western side, lava produced between 200 million and 2.5 million years ago mobilised underground water and formed glaciers as recently as four million years ago.
These findings were presented on 21 February at ESA's Mars Express Science Conference at ESTEC in Noordwijk, the Netherlands, where about 250 scientists from all over the world are discussing the first year of scientific results from Mars Express.
The colour images were processed using the HRSC nadir (vertical view) and three colour channels. The perspective views were calculated from the digital terrain model derived from the stereo channels.
For more information on Mars Express HRSC images, you might like to read our updated 'Frequently Asked Questions'.