Sunday, August 5, 2007

Phoenix Mars Liftoff

Credit: NASA

The Phoenix Mars Lander lifted off successfully early Saturday morning from Cape Canaveral aboard a Delta II rocket. If all goes well, the Phoenix Mars Lander will land high up in the Vastitas Borealis next year, on May 25, 2008 (see the Mission Landing Sites map below, based on the topographical map produced by MOLA on Mars Global Surveyor). Also below is the launch video and excerpts from two press releases. The launch video is fairly long (run time: 9:56), starting just before the T-4:00 mark and ending roughly around the T+3:00 mark, when the second stage of the spacecraft ignites.

From NASA:
The Phoenix spacecraft has separated from the Delta II rocket and ground controllers at NASA's Deep Space Network have acquired its signal and begun assessing its health. The solar panels that will power the mission's cruise phase will be deployed and Phoenix will be pointed to best receive solar power and communicate with Earth.

The spacecraft has oriented itself to the sun as it was programmed to do. It will use solar panels to generate electricity during the nine-month coast to Mars. A separate set of solar arrays is attached to the lander itself. (Source)

From the Associated Press:
The Phoenix Mars Lander won't be looking for evidence of life on Mars but rather traces of organic compounds in the baked and moistened samples, which would be a possible indicator of conditions favorable for life, either now or once upon a time.

If organic compounds are present on Mars, they're more likely to have been preserved in ice. That's why NASA is aiming for the planet's high northern latitudes, where ice is almost certainly lurking just beneath the surface.

Only about six inches of soft red soil should cover the ice, and so the digger shouldn't have to probe too deeply. The ice is expected to be as hard as concrete, and a drill on the scoop will help gather enough frozen samples. Some dirt and ice samples will be baked and their vapors analyzed. Other soil samples will be mixed with onboard water and the muddy soup examined by onboard microscopes.

"We're really going there just to understand whether the conditions might have been hospitable for microbial life at some point," said the University of Arizona's William Boynton, lead scientist for the oven experiment.

Even if organic molecules pop up, they could be from incoming meteorites, Boynton noted. "It is important, I think, to keep in mind that we are just looking for organic molecules to see if the conditions are right that they could survive," he said, "and that we aren't really going to be making any inference about whether these molecules are indicative of life."


NASA has never attempted to land a spacecraft on Mars at such a high northern latitude. A lander intended for the red planet's South Pole went silent immediately upon arrival in 1999. That failure, combined with the loss of the companion Mars orbiter, prompted NASA to cancel a 2001 lander mission. The parts from that scrapped mission were used for Phoenix, thus its name, which alludes to the mythological bird that rises from its own ashes.

Mars' North Pole would have been too cold for Phoenix to operate, and so scientists opted for a little lower latitude for touchdown. Phoenix will be shooting for 68.35 degrees north latitude, comparable to Greenland or northern Alaska, and 233 degrees east longitude. The lander will parachute down, with pulse thrusters easing its final descent.

Scientists chose the flattest, rock-free zone they could to ensure success. The target landing area is "Kansas flat," according to the spacecraft team, with few if any big rocks that could overturn the stationary three-legged lander or bump against its circular solar panels and jam them. The 772-pound lander will stretch 18 feet across once its solar panels are deployed on Mars, and its weather mast will tower 7 feet.

Phoenix should help pave the way for human visitors, especially if it confirms the presence of water ice in large amounts near the pole, said Michael Meyer, NASA's lead Mars scientist. That would be a tremendous resource, he noted. But if organic matter is indeed found, it could pose a dichotomy: "As Mars gets more interesting, you may not want to send humans right away until you learn out a little bit more about the red planet and find out whether or not life ever got started there."

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