NASA News: NASA Spacecraft Data Suggest Water Flowing On Mars

WASHINGTON -- Observations from NASA's Mars Reconnaissance Orbiter
(MRO) have revealed possible flowing water during the warmest months on Mars.

"NASA's Mars Exploration Program keeps bringing us closer to
determining whether the Red Planet could harbor life in some form,"
NASA Administrator Charles Bolden said, "and it reaffirms Mars as an
important future destination for human exploration."

Dark, finger-like features appear and extend down some Martian slopes
during late spring through summer, fade in winter, and return during
the next spring. Repeated observations have tracked the seasonal
changes in these recurring features on several steep slopes in the
middle latitudes of Mars' southern hemisphere.

"The best explanation for these observations so far is the flow of
briny water," said Alfred McEwen of the University of Arizona,
Tucson. McEwen is the principal investigator for the orbiter's High
Resolution Imaging Science Experiment (HiRISE) and lead author of a
report about the recurring flows published in Thursday's edition of
the journal Science.

Some aspects of the observations still puzzle researchers, but flows
of liquid brine fit the features' characteristics better than
alternate hypotheses. Saltiness lowers the freezing temperature of water.

Sites with active flows get warm enough, even in the shallow
subsurface, to sustain liquid water that is about as salty as Earth's
oceans, while pure water would freeze at the observed temperatures.

"These dark lineations are different from other types of features on
Martian slopes," said MRO project scientist Richard Zurek of NASA's
Jet Propulsion Laboratory in Pasadena, Calif. "Repeated observations
show they extend ever farther downhill with time during the warm season."

The features imaged are only about 0.5 to 5 yards or meters wide, with
lengths up to hundreds of yards. The width is much narrower than
previously reported gullies on Martian slopes. However, some of those
locations display more than 1,000 individual flows. Also, while
gullies are abundant on cold, pole-facing slopes, these dark flows
are on warmer, equator-facing slopes.

The images show flows lengthen and darken on rocky equator-facing
slopes from late spring to early fall. The seasonality, latitude
distribution and brightness changes suggest a volatile material is
involved, but there is no direct detection of one. The settings are
too warm for carbon-dioxide frost and, at some sites, too cold for
pure water. This suggests the action of brines which have lower
freezing points. Salt deposits over much of Mars indicate brines were
abundant in Mars' past. These recent observations suggest brines
still may form near the surface today in limited times and places.

When researchers checked flow-marked slopes with the orbiter's Compact
Reconnaissance Imaging Spectrometer for Mars (CRISM), no sign of
water appeared. The features may quickly dry on the surface or could
be shallow subsurface flows.

"The flows are not dark because of being wet," McEwen said. "They are
dark for some other reason."

A flow initiated by briny water could rearrange grains or change
surface roughness in a way that darkens the appearance. How the
features brighten again when temperatures drop is harder to explain.

"It's a mystery now, but I think it's a solvable mystery with further
observations and laboratory experiments," McEwen said.

These results are the closest scientists have come to finding evidence
of liquid water on the planet's surface today. Frozen water, however
has been detected near the surface in many middle to high-latitude
regions. Fresh-looking gullies suggest slope movements in
geologically recent times, perhaps aided by water. Purported droplets
of brine also appeared on struts of the Phoenix Mars Lander. If
further study of the recurring dark flows supports evidence of
brines, these could be the first known Martian locations with liquid water.

MRO is managed by JPL for NASA's Science Mission Directorate in
Washington. The University of Arizona's Lunar and Planetary
Laboratory operates HiRISE. The camera was built by Ball Aerospace &
Technologies Corp. in Boulder, Colo. Johns Hopkins University Applied
Physics Laboratory in Laurel, Md., provided and operates CRISM.

For more information about MRO, visit:

http://www.nasa.gov/mro

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Minnesota Scouts Call Space Station Astronauts

WASHINGTON -- Boy Scouts, Girl Scouts and other students in St. Paul,
Minn., will make a special call to the International Space Station on
Tuesday, Aug. 9 at 12:55 p.m. EDT.

The event includes a video link with Expedition 28 Flight Engineers
Mike Fossum and Ron Garan, which will be broadcast live on NASA
Television. Fossum is scoutmaster of a Boy Scout troop in Texas.

Scouts and students ages 7 to 13 can ask questions about how living
and working in space helps increase human understanding of the Earth,
science, and the universe. The children also will participate in
science and space-related activities before and after the
question-and-answer session.

The event will take place at Base Camp, Northern Star Council, Boy
Scouts of America's urban program center located at 201 Bloomington
Road at Fort Snelling, Minn. To attend, journalists must contact Kent
York at 612-760-8430.

The in-flight education downlink is part of a series with educational
organizations in the U.S. and abroad to improve teaching and learning
in science, technology, engineering and mathematics subjects. It is
an integral component of Teaching From Space, an agency education
program that promotes learning opportunities and builds partnerships
with the education community using the unique environment of space
and NASA's human spaceflight program.

For NASA TV information and schedules, visit:

http://www.nasa.gov/ntv

For information about NASA's education programs, visit:

http://www.nasa.gov/education

For more information about the International Space Station, visit:

http://www.nasa.gov/station

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NASA Holds Media Telecon To Announce NIAC Selections

WASHINGTON -- NASA will hold a media teleconference at 2 p.m. EDT on
Monday, Aug. 8, to announce the proposals selected for study under
the NASA Innovative Advanced Concepts, or NIAC, program.

The proposals were selected based on the concepts' potential to
transform our future space missions, enable new capabilities or
significantly alter current approaches to launching, building, and
operating space systems.

Each proposal will receive approximately $100,000 for one year to
advance the innovative space technology concept and help NASA meet
current operational and future mission requirements.

The teleconference panelists are:
-- Bobby Braun, NASA chief technologist, NASA Headquarters, Washington

-- Joe Parrish, director, Early Stage Innovation division, Office of
the Chief Technologist
-- Jay Falker, program executive, NIAC, Office of the Chief
Technologist

To participate, reporters must contact David Steitz at
david.steitz@nasa.gov or 202-358-1730, by 9 a.m. on Aug. 8 for
dial-in instructions.

Audio of the teleconference will be streamed live on NASA's website at:

http://www.nasa.gov/newsaudio

For more information about the NIAC program, visit:

http://go.usa.gov/K9K

For more information about NASA's Office of the Chief Technologist, visit:

http://www.nasa.gov/oct

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