[meteorite-list] HiRISE Camera Captures High-Resolution 3D Images of Mars

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon, 8 Dec 2008 13:53:54 -0800 (PST)
Message-ID: <200812082153.NAA28811_at_zagami.jpl.nasa.gov>

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

HiRISE Camera Captures High-Resolution 3D Images of Mars
December 8, 2008

The High Resolution Science Imaging Experiment, or HiRISE, team based at The
University of Arizona today released 362 three-dimensional images of Mars taken
by the HiRISE camera on NASA's Mars Reconnaissance Orbiter.

Other Mars-orbiting cameras have taken 3D views of Mars, but the HiRISE camera
- the most powerful camera ever to orbit another planet - can resolve
features as small as one meter, or 40 inches, across.

"It's really remarkable to see Martian rocks and features on the scale of a
person in 3D," said Alfred McEwen of UA's Lunar and Planetary Laboratory,
HiRISE principal investigator. "The level of detail is just much, much greater
than anything previously seen from orbit."

The 3D images, or anaglyphs, can be viewed on the HiRISE Web site
(http://hirise.lpl.arizona.edu/anaglyph) with inexpensive color filter glasses
commonly used for viewing 3D images and movies. The HiRISE Web site links to
information on where to purchase and how to make 3D red-cyan filter glasses.
Without 3D glasses, the Mars images appear out of register.

(In Tucson, UA's Flandrau Science Center, 1601 E. University Blvd., and
Starizona, 5757 N. Oracle Road, sell red-cyan filter glasses for $2 each.)

Seen in HiRISE 3D, Mars becomes a collection of deep panoramic views that leap
out from the computer screen.

"You'd swear you could touch the terrain," HiRISE operations manager Eric
Eliason said.

Striking stereo views include:

* Sixty-meter tall, or 200-foot-tall fractured mounds, probably composed of
solidified lava, on the southern edge of Elysium Planitia. The fractured
surface suggests that lava pushed the surface into domes, uplifting some sides
along the same fracture higher than others.
* Spectacular layers exposed on the floor about 2-and-a-half miles, or 4
kilometers, below the rim of Candor Chasma, which is a large canyon in the
Valles Marineris system. The canyon may once have been filled to its rim by
sedimentary layers of sand and dust-sized particles, but these have since
eroded, leaving patterns of elongated hills and layered terrain that has been
turned and folded in many angles and directions.
* Groups of gullies at different elevations along the wall of an unnamed crater
in Terra Cimmeria. The anaglyph image provides three-dimensional perspective on
the depth of the gullies and the amount of material deposited below the gullies.
Geological evidence suggests that the gullies may have formed by subsurface
water, rather than by snow or ice melting on the surface.

Other dramatic anaglyphs show a huge jumbled mass of rock that includes
megabreccia at a central peak in Ritchey crater, ejecta-formed channels and
mudflows at Hale crater, tightly folded rock layers lining the floor of
Tithonium Chasm, "spiders" created by carbon dioxide venting through south
polar layered deposits, and Martian glacier flows.

Eliason and the team at HiROC, the High Resolution Imaging Operations Center on
the UA campus, began processing stereo images in October. They automated some
of the software used in processing HiRISE images so two images of a stereo pair
could be fed into the software "pipeline" and correlated automatically.

"The real advance here is making this process semi-automated so we can really
crank through all these huge images," McEwen said. Producing anaglyphs from
stereo pairs is otherwise a tedious, time-consuming effort.

The HiRISE camera has so far taken 950 stereo image pairs. The camera features a
half-meter, or 20-inch, diameter primary mirror and a focal plane mechanism that
can acquire up to a 3.6 megapixel image in about 11 seconds.

The anaglyphs are among 1,642 observations containing 3.6 terabytes of data and
148,000 image products that HiRISE released today to the Planetary Data System,
or the PDS, the NASA mission data archive.

Since HiRISE began the science phase of its mission in November 2006, the HiRISE
team has released a total 867,430 image products, or 30.2 terabytes of data.
That is by far the greatest volume of data a space experiment has delivered to
the PDS, and well more than twice the data volume some HiRISE team members
expected to get during the primary science phase.

The HIRISE camera was designed to take images at high-convergence angles so
researchers can calculate the thickness of surface features to within about 10
inches, or 25 centimeters. High-convergence angles used to get quantitative
measurements aren't always best for making anaglyphs, McEwen said.

In addition, if the two stereo images on two different orbits were taken far
enough apart in time, the illumination or air opacity may have changed, or
frost or dust devils may have appeared in one of the images, so paired images
don't always match that well, he added.

"Nevertheless, many of these stereo anaglyphs are very interesting and useful to
us in understanding the topography," McEwen said.

"There's a lot of science to be done by just looking at these directly and
understanding what's up and what's down," he added. "Anaglyphs can definitely
change how we interpret things, and help us focus on how to proceed when it
comes to prioritizing some science tasks."

Binocular vision gives humans wearing 3D color glasses the ability to see
anaglyphs in three dimensions the same way they see in three dimensions through
a View-Master viewer or a Victorian-era stereoscope. The same scene is viewed in
two pictures taken from slightly different angles. Each eye has its own slightly
different view, which the brain fuses together into a single picture with depth.

With the colored glasses, the red filter for the left eye sees only red in the
picture, the cyan filter for the right eye sees only blue-green in the picture,
and the brain correlates the images. The glasses work for viewing stereo
pictures in print or on TV, movie and computer screens.

The Mars Reconnaissance Orbiter is managed by the Jet Propulsion Laboratory,
Pasadena, Calif., for NASA's Science Mission Directorate, Washington. Lockheed
Martin Space Systems of Denver built the spacecraft. The UA operates the HiRISE
camera, built by Ball Aerospace and Technologies Corp. of Boulder, Colo.

SCIENCE CONTACTS:
Alfred McEwen (520-621-4573; mcewen at pirl.lpl.arizona.edu)
Eric Eliason (520-626-0764; eeliason at pirl.lpl.arizona.edu)

WEB LINKS:
HiRISE: http://hirise.lpl.arizona.edu
MRO: http://www.nasa.gov/mro
Received on Mon 08 Dec 2008 04:53:54 PM PST