ചൊവ്വയില്‍ ഒഴുകുന്ന വെള്ളത്തിന്‍റെ സാന്നിധ്യം

ചൊവ്വയില്‍ ഒഴുകുന്ന വെള്ളത്തിന്‍റെ സാന്നിധ്യം നാസ (NASA) കണ്ടെത്തി. ചൂടുകുടുതലുള്ള മാസങ്ങളില്‍ ദ്രവരൂപത്തില്‍ ഒഴുകുന്ന വെള്ളത്തിന്‍റെ സാന്നിധ്യം കണ്ടെത്തി. വേനല്‍ക്കാലത്ത് ദ്രൂവരൂപത്തിലാകുന്ന ജലം ശരത്കാലത്ത് മഞ്ഞുപാളികളായി ഉറയുന്നുവെന്ന് നാസ പറയുന്നു.

Oblique View of Warm Season Flows in Newton Crater

An image combining orbital imagery with 3-D modeling shows flows that appear in spring and summer on a slope inside Mars' Newton crater. Sequences of observations recording the seasonal changes at this site and a few others with similar flows might be evidence of salty liquid water active on Mars today. Evidence for that possible interpretation is presented in a report by McEwen et al. in the Aug. 5, 2011, edition of Science.

This image has been reprojected to show a view of a slope as it would be seen from a helicopter inside the crater, with a synthetic Mars-like sky. The source observation was made May 30, 2011, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. Color has been enhanced. The season was summer at the location, 41.6 degrees south latitude, 202.3 degrees east longitude.

The flow features are narrow (one-half to five yards or meters wide), relatively dark markings on steep (25 to 40 degree) slopes at several southern hemisphere locations. Repeat imaging by HiRISE shows the features appear and incrementally grow during warm seasons and fade in cold seasons.

HiRISE is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the spacecraft.

Other imagery related to these new findings from the Mars Reconnaissance Orbiter is at http://www.nasa.gov/mission_pages/MRO/multimedia/gallery/gallery-index.html .

Image credit: NASA/JPL-Caltech/Univ. of Arizona

Warm-Season Flows on Slope in Newton Crater

This series of images shows warm-season features that might be evidence of salty liquid water active on Mars today. Evidence for that possible interpretation is presented in a report by McEwen et al. in the Aug. 5, 2011, edition of Science.

These images come from observations of Newton crater, at 41.6 degrees south latitude, 202.3 degrees east longitude, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. In time, the series spans from early spring of one Mars year to mid-summer of the following year. The images have been adjusted to correct those taken from oblique angles to show how the scene would look from directly overhead.

The features that extend down the slope during warm seasons are called recurring slope lineae. They are narrow (one-half to five yards or meters wide), relatively dark markings on steep (25 to 40 degree) slopes at several southern hemisphere locations. Repeat imaging by HiRISE shows the features appear and incrementally grow during warm seasons and fade in cold seasons. They extend downslope from bedrock outcrops, often associated with small channels, and hundreds of them form in rare locations. They appear and lengthen in the southern spring and summer from 48 degrees to 32 degrees south latitudes favoring equator-facing slopes. These times and places have peak surface temperatures from about 10 degrees below zero Fahrenheit to 80 degree above zero Fahrenheit (about 250 to 300 Kelvin). Liquid brines near the surface might explain this activity, but the exact mechanism and source of the water are not understood.

The series is timed to dwell two seconds on the first and last frames and one second on intermediate frames, though network or computer performance may cause this to vary.