[meteorite-list] HiRISE Releases Color Images, Movie of Prospective Landing Site on Mars

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed, 10 Oct 2007 14:06:03 -0700 (PDT)
Message-ID: <200710102106.OAA13553_at_zagami.jpl.nasa.gov>

FROM: Lori Stiles (520-626-4402; lstiles at u.arizona.edu)

HiRISE RELEASES COLOR IMAGES, MOVIE OF PROSPECTIVE LANDING SITES ON MARS

- Sent October 10, 2007

TUCSON, Ariz. -- The High Resolution Imaging Science Experiment, or HiRISE,
on NASA's Mars Reconnaissance Orbiter has added a new dimension to its views
of Mars. The dimension is color.

The University of Arizona-based HiRISE team today released 143 color images
valuable to researchers studying possible landing sites for NASA's Mars
Science Laboratory, a mission to deploy a long-distance rover carrying a
deck of sophisticated science instruments on Mars in 2010. The color images
are online at the HiRISE Website, http://hirise.lpl.arizona.edu, and are
available through the Planetary Data System, NASA's space mission data
archive.

The powerful HiRISE camera has taken more than 3,500 huge, sharp images
released in black-and-white since it began science operations in November
2006. The camera carries 10 red-filter detectors, two blue-green filter
detectors and 10 infrared detectors that record different colors.

HiRISE is also releasing a color movie, scrolling over one potential Mars
Science Laboratory landing site in Nili Fossae, at 21 degrees north latitude
and 74 degrees east latitude. The animation shows a range of enhanced colors
that correspond to what Mars Reconnaissance Orbiter's imaging spectrometer,
called CRISM, has determined to be hydrated clay minerals and unaltered
volcanic rocks. Link to the movie at
http://hirise.lpl.arizona.edu/media/clips/PSP_003086_2015_short.mov

"The clay minerals are especially promising in the search for ancient life
on Mars," said UA Professor Alfred S. McEwen, HiRISE principal investigator.

Beginning this week, images will be released in color as well as
black-and-white on the HiRISE Website. The colors are false color, not the
way Mars would look to human eyes. The images are processed to maximize
color differences, a technique useful for analyzing landscapes.

"Color data are proving very useful in interpreting geologic processes and
history on Mars," McEwen said. "The images we're releasing today include
views of some of the most exciting and compositionally diverse areas on the
planet. They are really interesting."

In a Herculean effort, HiRISE team members developed computer software that
automatically processes images from the different color filters into color
images.

"The technical hurdle has been that the sets of different color detectors
are staggered within the camera focal plane array, and the spacecraft isn't
perfectly steady as it operates in space," HiRISE operations manager Eric
Eliason said.

The spacecraft has excellent pointing control thanks to superb engineering,
but HiRISE pixels cover an extremely small angular diameter, which gives the
camera its ability to sample the surface at 30 centimeters per pixel (about
12 inches) from 300 kilometers (about 185 miles) above the surface. The
slightest spacecraft motion causes shifts in the camera pointing in
unpredictable ways.

There's only a split-second time lag between the time each color filter
records the same spot on Mars as the camera view sweeps over the planet, but
that's enough time for spacecraft motion to knock the colors out of register
by up to a few pixels. "You can't just take the different color images and
lay them down on each other adjusting only for the slight time lag and get a
sharp picture," Eliason said.

HiRISE software developer Guy McArthur and applied mathematics undergraduate
student Sarah Mattson put a lot of work into developing code that now
successfully correlates the data from the different detectors. McArthur
developed software that automates color correlation processing at HiROC, the
HiRISE Operations Center at the UA.

Color is a boon to geologists who have been trying to discriminate different
surface materials and their relation to the topography, McEwen said. "Color
clearly identifies basic material distinctions like dust, sand or rocks,
light-toned layered material, and frost or ice," he said. Color also helps
geologists correlate layers in the Martian terrain. And scientists will be
able to combine HiRISE data with CRISM data to make detailed maps of
minerals and soil types on the planet.

A single HiRISE image will often be a multigigabyte image that measures
20,000 pixels by 50,000 pixels, which includes a 4,000-by-50,000 pixel
region in three colors. It can take a computer up to three hours to process
such an image.

McEwen decided to process images that support selection of the Mars Science
Laboratory, or MSL, landing site first.

"The MSL is holding a landing site workshop later this month, so the color
images had to be ready a couple of weeks in advance to be useful," McEwen
said. The color images released today were taken over or near about 30
proposed landing sites for the 2010 mission.

The UA-led Phoenix Scout Mission to Mars was saved from being launched to a
dangerous, boulder-strewn landing site when researchers saw HiRISE images
taken soon after the camera began taking science images in late 2006. Images
from HiRISE and from Arizona State University's Thermal Emission Imaging
System on Mars Odyssey were used in choosing where the Phoenix spacecraft
will land on May 25, 2008.

McEwen said the HiRISE camera will try to image the Phoenix spacecraft
landing site again in January, although it could be so cloudy the camera
might have to wait an extra month or two for a clear view.

Information about the Mars Reconnaissance Orbiter is online at
http://www.nasa.gov/mro. The mission is managed by NASA's Jet Propulsion
Laboratory, a division of the California Institute of Technology, for the
NASA Science Mission Directorate, Washington, D.C. Lockheed Martin Space
Systems, of Denver, is the prime contractor and built the spacecraft. HiRISE
is operated by the UA. Ball Aerospace and Technologies Corp., of Boulder,
Colo., built the HiRISE instrument.

CONTACT:
Alfred S. McEwen (520-621-4573; mcewen at pirl.lpl.arizona.edu)
Eric Eliason (520-626-0764; eeliason at pirl.lpl.arizona.edu)
Received on Wed 10 Oct 2007 05:06:03 PM PDT