UA technology on board orbiter bound for Mars

By Evan Pellegrino
Arizona Daily Wildcat
August 22, 2005

The Mars Reconnaissance Orbiter is now on its way to the red planet after a successful launch Aug 12, when it blasted off from Kennedy Space Center, Florida two days after its scheduled departure.

The orbiter has two main scientific objectives; it will serve as a Mars weather satellite and also study the composition and structure of the planet in greater detail than before.

The launch vehicle, MRO's taxi, was deliberately launched to slightly miss its destination. If the team lost communication with the craft after launch, they wouldn't want it crashing into the red planet, destroying its natural essence, said Richard Zurek, the project scientist with NASA's Jet Propulsion Laboratory (JPL) in Pasadena California.

Once MRO was in space and communication with the craft remained, the team of scientists at JPL commanded the craft to burn its engines for 18 seconds. This course-maneuver correction got the probe right on target to Mars.

Assuming everything goes well, the mission will provide scientists with "10 times (more information) than any previous Mars mission," said Alfred S. McEwen, UA professor of planetary sciences and scientist at the Lunar & Planetary Laboratory.

McEwen proposed the mission to NASA in 2001.

The mission was slated to depart Aug. 10 but a delay occurred due to a failure with the launch vehicle's gyros, which control the stability of the craft.

After MRO's operation team successfully fixed the glitch for a Thursday launch, the craft was further delayed by weather and then by an error in a rocket fuel gage.

One of the gages read the rocket was full, while the other said it wasn't, Zurek said.

"When you're dealing with a $700-million space craft you want it to go right," McEwen said. "Any concern means you hold off on the launch."

Once the launch was set for Friday, McEwen and Zurek said the excitement of scientists grew as the team gathered for takeoff and the countdown began.

"We had a great view as it slowly rose up over the pad," said Zurek.

McEwen admitted he "was holding (his) breath" as the rocket pushed away from Earth.

Ingrid Dauber, a UA scientist who also attended the launch, said it was exciting to be a part of such a big mission.

Dauber will be communicating with the probe's high-resolution camera, which is powered by a half-meter telescope.

Developed by McEwen, the High Resolution Imaging Science Experiment, or "HiRISE," is the largest telescope to ever leave Earth's orbit.

HiRISE will capture much higher resolution images of Mars' surface and features then ever previously seen by human eyes.

Dauber said she will command the camera from the HiRISE Operations Center (HiRoc) here on campus. Located at the UA's Lunar and Planetary Laboratory, HiRoc will be the heart of the scope, serving as a dominion for the camera.

HiRoc, in communication with JPL, is in charge of HiRISE "observation planning, uplink, downlink, data processing and instrument monitoring." All of the images captured by HiRISE will be processed and seen first by UA scientists.

Dauber will tell HiRISE how and when to take pictures through an "X band" transmission with MRO. The team will also experiment with a "Ka band" transmission, which if successful, will allow the probe to send and receive information three times faster than X band, according to Zurek.

HiRISE will also help determine landing sites and rover paths for future missions to Mars.

In addition to HiRISE, the probe contains a "meter scale," which will show scientists the scale of features on Mars and help determine obstacles for future landing missions, McEwen said.

HiRISE will get its first in-space action Sept. 8 when McEwen, Dauber and the rest of the HiRISE team will photograph Earth's moon, one of five scheduled calibration sequences on route to Mars.

Zurek said this sequence will help "test out equipment on objects already familiar."

The craft has already used its weather camera to look back on Earth with the same intentions.

MRO is also home to an optical navigation camera, which will study the configuration of the Martian moons, Phobos and Deimos.

These configurations will act as a navigational tool for MRO's mission and for future red planet explorations. The data collected by MRO will allow future missions to enter Mars' atmosphere at any desired point, Zurek said.

Early explorers on Earth used stars to determine their ships' locations at sea. Today, scientists will use the clockwork rotations of Martian moons and their relative location to each other to determine a probe's relation to locations in Mars' atmosphere.

An instrument provided by the Italian Space Agency will give scientists a view of a half-mile under Mars' surface. Previous missions to the planet have indicated the presence of hydrogen, thus pointing to the presence of ice. The MRO could uncover evidence that ice goes deeper into the surface than currently known.

"The known ice is merely the tip of the iceberg," Zurek said.

For fuel efficiency, MRO will not be traveling to Mars in a straight line. The probe will use Earth's elliptic path and travel to the other side of the Sun before approaching Mars' orbit.

When it approaches Mars in seven months, the craft will blast its jets to begin air-breaking into orbit. The probe's antennae and solar panels will add to the friction necessary for a successful orbit insertion. If everything goes as planned, the spaceship will settle into an egg-shaped orbit 60 miles above Mars' surface.