HiRISE researchers will power the HiRISE camera the week of March 20. It will begin taking pictures 18 hours later, and it will take pictures during two orbits. NASA Jet Propulsion Laboratory mission specialists will decide exactly which orbits will be HiRISE imaging orbits after Mars orbit insertion on March 10.

These will be the camera's only photos for the next six months because it will be turned off while the spacecraft "aerobrakes." This involves dipping repeatedly into the upper atmosphere to scrub off speed and drop into successively more circular orbits.

The first images will be highly experimental because the team is trying many algorithms and systems for the first time, so things could go wrong, McEwen said. "However, we are sure to learn important lessons about how to operate the spacecraft and HiRISE."

Also, the geometries of the early orbits may be less than ideal for the HiRise camera's test-image swath. And there's a chance that atmospheric dust or ice hazes could obscure the surface because it's early fall in the southern hemisphere.

The camera will take pictures of the middle latitudes of the southern hemisphere, a region where a number of geologically recent gullies have been seen, gullies possibly carved by water. Scientists won't know the exact area they'll photograph until the spacecraft is safely captured into orbit around Mars.

The camera's first images will be taken when the MRO is flying between about 2,500 miles and 600 miles (4,000 km and 1,000 km) above the planet. After aerobraking, the camera will fly just outside the planet's atmosphere at only 190 miles (about 300 km).

Some of the camera's first targets next fall will be of potential landing sites for UA's Phoenix Mission lander, which is slated to reach the Martian surface in May 2008. This Scout-class lander mission is led by LPL scientist Peter Smith. The Phoenix Mission will communicate with Earth using MRO's high-data-rate relay.

These first images will reach UA at the HiRISE Operations Center (HiROC), where researchers will be remotely controlling the camera. HiROC is in the C. P. Sonett Space Sciences Building, 1541 E. University Blvd, and its operations include observation planning, uplink, downlink, instrument monitoring, and data processing and analysis.

"The first views should be the sharpest, with minimal blurring from spacecraft motions," said HiROC manager Eric Eliason. The second orbit images, or "jitter" images, will be taken to show how vibrations from other spacecraft instruments affect HiRISE images, Eliason added.

"We want to acquire images of Mars that fill the 20,000-pixel wide field-of-view so we can learn how to best process these huge images," McEwen said. "We'll acquire the images at altitudes higher than 1,000 kilometers (about 600 miles), so the resolution will be worse than a meter-per-pixel scale, compared to the one-third meter-per-pixel resolution scale that we'll get in final orbit".

(EDITORS: Media are welcome at HiROC as the team views the camera's first images. For more information, contact HiRISE team member Loretta McKibben, 520-626-7432, loretta @ lpl.arizona.edu, or Lori Stiles, University Communications, 520-626-4402, lstiles@u.arizona.edu).

HiRise: "The People's Camera"
The HiROC team expects to process about 10,000 large-to-very-large, high-resolution images during the 25-month-long primary mission.

Members of the public will be able to suggest some of the imaging target sites using special Web software that will be available in a few months. For this reason, the HiRise camera is called the "people's camera." All images will be released as soon as possible to the public and scientific community after they are processed.

The 145-pound (65 kg) HiRISE camera features a 20-inch (half-meter) primary mirror. The $40 million camera, which was built by Ball Aerospace & Technologies Corp. in Boulder, Co., will take ultra-sharp photographs that cover 3.5-mile-wide (6 kilometer) swaths of the Martian landscape. Researchers will be able to see rocks and other geologic features in these photos that are as small as 40 inches (one meter) across.

The HiRISE camera will take pictures in stereo and color while it flies at more than 7,800 mph (3 and 1/2 km per second) in its final orbit.

Once in low-Mars orbit, MRO will examine the planet in unprecedented detail, returning more data than all prior Mars missions combined. Its instrument payload will study water distribution -- including ice, vapor and liquid -- as well as geologic features and minerals. The orbiter will also support future missions to Mars by examining potential landing sites and by providing a high-data-rate relay for communications back to Earth.

The MRO mission is managed for the NASA Science Mission Directorate by JPL, a division of the California Institute of Technology in Pasadena, Calif. Lockheed Martin Space Systems in Denver, Colo. is the prime contractor for the project and built the spacecraft.



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