Journal of Science
New Study Challenges Long-Held Theory of Fate of Mars’ Water
Grey Hautaluoma / Alana Johnson
NASA Headquarters, Washington
grey.hautaluoma-1@nasa.gov / alana.r.johnson@nasa.gov
Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
andrew.c.good@jpl.nasa.gov
This global view of Mars is composed of about 100 Viking Orbiter images. Credit: NASA/JPL-Caltech/USGS
The new science results indicate that a large quantity of the Red Planet’s water is trapped in its crust rather than having escaped into space.
Billions of years ago, according to geological evidence, abundant water flowed across Mars and collected into pools, lakes, and deep oceans. New NASA-funded research shows a substantial quantity of its water – between 30 and 99% – is trapped within minerals in the planet’s crust, challenging the current theory that due to the Red Planet’s low gravity, its water escaped into space.
Early Mars was thought to have enough water to have covered the whole planet in an ocean roughly 100 to 1,500 meters (330 to 4,920 feet) deep – a volume roughly equivalent to half of Earth’s Atlantic Ocean. While some of this water undeniably disappeared from Mars via atmospheric escape, the new findings, published in the latest issue of Science, conclude it does not account for most of its water loss.
Read the rest of this entry »Antarctica’s Effect on Sea Level Rise in Coming Centuries
Esprit Smith
Jet Propulsion Laboratory, Pasadena, Calif.
There are two primary causes of global mean sea level rise – added water from melting ice sheets and glaciers, and the expansion of sea water as it warms. The melting of Antarctica’s ice sheet is currently responsible for 20-25 percent of global sea level rise.
But how much of a role will it play hundreds of years in the future?
The Many Faces of Rosetta’s Comet 67P
Markus Bauer
European Space Agency, Noordwijk, Netherlands
M. Ramy El-Maarry
University of Colorado
Matt Taylor
ESA Rosetta project scientist
NOTE: Make sure you check 0ut the accompanying Space Photo Exploration page for Comet 67P/Churyumov-Gerasimenko
Images returned from the European Space Agency’s Rosetta mission indicate that during its most recent trip through the inner solar system, the surface of comet 67P/Churyumov-Gerasimenko was a very active place – full of growing fractures, collapsing cliffs and massive rolling boulders. Moving material buried some features on the comet’s surface while exhuming others. A study on 67P’s changing surface was released Tuesday, March 21, in the journal Science.
“As comets approach the sun, they go into overdrive and exhibit spectacular changes on their surface,” said Ramy El-Maarry, study leader and a member of the U.S. Rosetta science team from the University of Colorado, Boulder. “This is something we were not able to really appreciate before the Rosetta mission, which gave us the chance to look at a comet in ultra-high resolution for more than two years.”
