Mars orbiter clears hurdle
Craft circling planet after dangerous 'orbit insertion' maneuver
By Peggy Mihelich
The spacecraft had to fire its engines close enough to Mars that it would get caught by the planet's gravity.
YOUR E-MAIL ALERTS
(CNN) -- The Mars Reconnaissance Orbiter, on a two-year mission to study the Martian atmosphere and surface, and search for water, pulled off a dangerous and tricky maneuver known as "orbit insertion" and began circling the red planet Friday.
"It was picture perfect. We could not have planned it any better," MRO Project Manager Jim Graf said.
The spacecraft fired its six main engines at 4:24 p.m. ET and was captured by Mars' gravity. The burn lasted 27 minutes.
"Burn baby burn," a team member at NASA's Jet Propulsion Laboratory in California said when the maneuver began.
Twenty-one minutes in, the spacecraft disappeared behind Mars, and was out of radio contact with mission control for a nerve-wracking half-hour.
At 5:16 p.m., the team erupted in cheers when a signal was received back from the craft.
"Right on the money ... look at that!" yelled a jubilant mission control worker.
This stage of a space mission is hazardous: NASA is 2 for 4 in recent attempts at Mars orbit insertion.
"In the last 15 years, NASA's lost two spacecraft out of four that they sent to the planet in this very phase ... getting into orbit is not easy," Graf said.
MRO is expected to return more data to Earth than all previous Mars missions combined.
"I think that this mission will re-write the science books on Mars," Graf said.
"Every time that we send different spacecraft to Mars they teach and poke at the planet -- its atmosphere, at the surface, and, in our case, under the surface, and they solve mysteries," he said.
MRO was launched August 12 atop an Atlas V rocket from Cape Canaveral Air Force Station, Florida. (Watch an overview of Mars Reconnaissance Orbiter's mission -- 1:49)
The $720 million mission is part of NASA's Mars Exploration Program, a series of spacecraft sent to the planet to establish ongoing surface and orbit observations of the planet's climate and geography.
It will join Mars rovers Spirit and Opportunity and fellow orbiters Mars Odyssey and Mars Global Surveyor and the European Space Agency's Mars Express. (Learn about other missions to the Red Planet)
The MRO carries six instruments, including the most powerful telescopic camera ever flown to another planet. (Explore the spacecraft)
Now that MRO is in orbit, the team will begin the six-month process of changing the craft's initial orbit to one that is optimal for scientific observation.
This orbit adjustment process is called "aerobraking" -- a high-wire space act where MRO makes small dips into the Martian atmosphere and uses the drag on the craft to slow it down just enough to change its orbit.
It's a delicate balance: "You don't want to go too deep, because if you do then the friction will overheat the components on the spacecraft," MRO project scientist Rich Zurek said.
Scientific observation is slated to begin in November and take place over two years -- one Martian year.
MRO will act as both a geological explorer and weather satellite. (See an overview of MRO's science objectives)
Two instruments will study the Martian atmosphere, looking at cloud formation and seasonal temperature change.
Zurek said, "The annual change on Mars is just like on the Earth, the seasons are pretty pronounced."
The team wants to understand how long those seasons last, and how much water and dust is moving around the atmosphere.
A powerful high-resolution camera will be able to see features on the planet as small as a kitchen table.
"We want to look for places where there was water for an extended period of time and potentially had an energy source, like a hot spring, because that's where you would expect life to have developed," Zurek said.
An Italian Space Agency radar called SHARAD will probe a third of a mile below the surface for signs of water ice -- a big permafrost zone that may extend much deeper into the planet. Scientists suspect past water that was in the atmosphere might now be frozen deep underground.
The probe's sensors also will look for landing sites for future spacecraft including a manned mission to Mars. (Take a Mars quiz)
Once observations are complete in December 2008 MRO will serve as a communications relay between future spacecraft and scientists back on Earth.
|© 2007 Cable News Network.
A Time Warner Company. All Rights Reserved.
Terms under which this service is provided to you.
Read our privacy guidelines. Contact us. Site Map.