by David Edwards
August 4, 2011
NASA presented Thursday what may be the strongest evidence yet of
liquid water on the surface of Mars.
Pictures taken by the powerful
HiRISE camera aboard the Mars
Reconnaissance Orbiter (MRO) showed
fingers of dark material running
down rocky slopes facing the equator during spring and summer
Scientists believe that this represents
a significant sign that briny water is flowing on the surface of the
The dark stripes, approximately 0.5 yards wide and hundreds of yards
long, appear during the warm months and then disappear again in cold
The salty surface of Mars means that liquid water would be
salty as well, making it less likely to freeze at the observed
"These dark lineations are different
from other types of features on Martian slopes," MRO project
scientist Richard Zurek
said in a press advisory.
observations show they extend even farther downhill with time
during the warm season."
Lead researcher Alfred McEwen
Discovery News the latest pictures were not a smoking gun and
laboratory tests could provide more evidence.
"Whether this is related to Mars'
habitability or not, I think you'd need a lander or something to
go investigate in more detail. This (discovery) provides places
where there is water accessible to the surface," he added.
"What's really exciting to me is that it shows a new active
phenomenon on Mars. It shows how little we really know."
Watch this video from NASA:
Potential Mars Water Find a "Big Deal"
by Clara Moskowitz
August 10, 2011
appear in spring and summer on a slope inside Mars' Newton crater
(NASA/JPL-Caltech/Univ. of Arizona)
Claims of water on Mars have been made
before, but a new discovery of potential liquid water on the Red
Planet's surface last week is still making waves in the science
What differentiates the new find from previous discoveries is the
fact that it's the strongest evidence yet for liquid water, as
opposed to ice, and it's on the Martian surface, as opposed to miles
underground where it would be difficult to verify its presence.
The research is based on observations by NASA's Mars
Reconnaissance Orbiter, which observed seasonal changes in
slopes carved into the planet's surface that appear most likely to
have been formed by
flowing salty, briny water.
"In the last 15 years, we've
certainly discovered that
Mars has water," said one of
the researchers, geophysicist Philip Christensen of Arizona
State University in Tempe, during an Aug. 4 news conference
announcing the find.
"Much of that water is frozen. What
makes these new observations so interesting is that they occur
at much lower latitudes where temperatures are much warmer and
where it's actually possible for liquid water to exist."
Big find on
Scientists not involved with the project agree that the discovery
could be big.
"If the features identified,
recurring slope lineae (RSL),
can be confirmed to represent briny flows, this would be a very
significant finding," said MIT scientist Christopher Carr, who
is building an instrument that could
detect DNA and RNA on Mars, if
"It wouldn't dramatically change our
understanding of present-day Mars as generally cold and dry, but
it would be important to the search for life on Mars."
Liquid water is a treasure trove for
scientists because of the potential it offers for extraterrestrial
All life on Earth requires liquid H2O
to survive, and researchers suspect the same may be true elsewhere.
"Yeah it's a big deal," said Robert
Zubrin, president and founder of the Mars Society. "The idea
that there's liquid water on Mars today at the surface means
could be life on Mars today
at the surface."
What the Possibility of Water on Mars Means)
The search for
Not only does the new discovery rekindle hopes that Mars hosts life,
but it offers the chance that finding it might not be as difficult
as once thought.
"Before this experiment, you would
say looking for life on Mars is going to be tough" because it
would involve digging deeply to the hidden caches of liquid
water thought to exist deep underground, said Seth Shostak,
senior astronomer for the Search for Extraterrestrial
Intelligence (SETI) Institute in Mountain View, Calif.
"Now maybe it's gotten much easier
to do an experiment for life on Mars, which involves just
digging a hole a couple feet deep. You might do an experiment
that really could pay off."
Until now, many searches for life have
also focused on the Red Planet's potential for past habitability on
the surface, when Mars was thought to be a much wetter world.
"Identification of environments
where life might be able to survive on present-day Mars could
shift our focus from past to present-day habitability," Carr
"The subsurface might be one good
place to look, but areas with potential liquid brines at the
surface are much more accessible."
Zubrin, who has long been a proponent of sending people to
explore Mars, said the find boosts the rationale for such a mission.
"That there is water on the surface
means that explorers could go to Mars and potentially find
extant life on the surface of Mars," Zubrin told SPACE.com.
"It underscores the reason why Mars
should be the target for human exploration. You're not going to
find life on the moon, you're not going to find life on an
asteroid. We need to send human explorers to the complex
environments where the complex skills of human beings are
But before we start counting our
Martians before they hatch, all the scientists advised caution until
more data is available to prove that the slopes are actually caused
"It's very exciting, but it's too
early to know for sure without more data," Carr said.
He and Shostak both pointed out that
spectral imaging, which looks for the unique chemical signature of
water in the images, has not been able to verify the presence of the
compound on Mars.
"The expected signature of water has
not been detected in the RSLs - this may be a problem of
resolution and sensitivity, but could also be due to a lack of
water in RSLs," Carr wrote in an email.
"There are potential other
explanations that don't involve brines, like movement of dry
particles (mass-wasting). So, it's very exciting, but it's too
early to know for sure without more data. In the end, the data
will win no matter what we want to believe."