NASA recently released an image of a large new gully
taken by a spacecraft on Mars. The picture was taken by the HiRISE
camera located on NASA’s MRO (Mars Reconnaissance Orbiter). The new
gully is located on a crater wall slope in Mars’ mid-southern latitudes
and actually photographed on May 25, 2013
The new gully, which is very similar to a river channel here on
Earth, appears to have been formed in the last three years. NASA
officials reported that the new gully wasn’t present in HiRISE photos of
that area taken on Nov. 5, 2010. A NASA release states: “The dates of
the images are more than a full Martian year apart, so the observations
did not pin down the Martian season of the activity at this site.”
NASA officials note that the new gully was probably “not carved out
by flowing water.” They stated that “before-and-after HiRISE pairs of
similar activity at other sites demonstrate that this type of activity
generally occurs in winter, at temperatures so cold that carbon dioxide,
rather than water, is likely to play the key role.”
Despite this NASA scientists seem to be keeping an open mind to other
possibilities. After all, they have previously reported that the Mars Reconnaissance Orbiter (MRO)
has captured images of other Martian features that do appear to be
associated with liquid water such as RSL (recurring slope lineae) or
“dark slopes”.
In fact, the recurring slope lineae creep down crater walls and
similar slopes during warm weather on Mars. Some of the research team
believes the dark slopes are caused by a specific kind of briny water
that includes some sort of iron-based antifreeze. Additionally, NASA’s
Curiosity rover found an old lake-and-stream system close to its landing
site on Mars that researchers believe could very well have “supported
microbial life billions of years ago.”
At this time, however, there is no direct or conclusive evidence of
any water at these dark slope sites. Scientists continue the elusive
search, however, because if water does indeed flow anywhere on the
surface of the present-day Red Planet
it would indicate that Mars would be much more likely to host life.
After all, life on Earth is present anywhere one finds liquid water.
(Image courtesy Sott/NASA/JPL-Caltech/Univ. of Arizona)
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