London, March 29 (IANS): As scientists the world over are excited about the presence of water on Mars, a new research on meteorites reveals how the water vanished from the Martian surface.

The large amounts of water escaped into space within the first half-billion years of Mars' existence while remaining water froze and may have formed reservoirs of ice still hidden below the surface, a promising study shows.

“The new study now strengthens the case that huge amounts of ice remain hidden on Mars,” lead author Hiroyuki Kurokawa of Nagoya University in Japan was quoted as saying.

According to the scientists, most of the water on Mars probably escaped because the planet's gravity was not sufficient to hold onto its atmosphere.

Over time, the water on Mars evaporated and drifted away into space.

To estimate this, the researchers analysed three different meteorites from 4.5 billion years ago, 4.1 billion years ago, and sometime between 170 million and 180 million years ago.

They created a timeline of water loss. It showed that Mars may have lost several times more water between 4.5 billion and 4.1 billion years ago than the past four billion years.

“There must be a lot of water still on Mars today - several times more than the water frozen at the poles,” Kurokawa suggested in the paper that is scheduled to be published in the journal Earth and Planetary Science Letters.