Article Posted on : - Aug 06, 2011

Mars’ northern polar regions. An ESA photo

PARIS (BNS): ESA has released a new image showing a part of the northern polar region of Mars during the summer solstice taken by Mars Express on 17 May 2010.

The solstice is the longest day and the beginning of the summer for the planet’s northern hemisphere.

The ice shield is covered by frozen water and carbon dioxide ice in winter and spring but by this point in the martian year all of the carbon dioxide ice has warmed and evaporated into the planet’s atmosphere, an ESA release said.

Only water ice is left behind which shows up as bright white areas in the picture captured by the orbiter’s High-Resolution Stereo Camera. From these layers, large bursts of water vapour are occasionally released into the atmosphere.

The polar ice follows the seasons. In winter, part of the atmosphere re-condenses as frost and snow on the northern cap. These seasonal deposits can extend as far south as 45°N latitude and be up to a metre thick, it said.