News of science:Named after the bellicose god of war, Mars has claimed many a victim, and the latest one, a Russian space probe, looks likely to tumble to Earth very soon.
Launched Nov. 8 from Kazakhstan, Russia's Phobos-Grunt (grunt is Russian for ground or soil) mission aimed for a first landing of a probe on the martian moon, Phobos. The $163 million spacecraft also carried a piggybacked Chinese Mars orbiter added late to the mission, and a Planetary Society microbe experiment.
Sadly, the spacecraft reached orbit around Earth but failed to fire the rocket that would send it on an eight-month interplanetary trip. The cause of the failure is the subject of an open investigation by Russian space officials.
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"Way too ambitious, and way too underfunded, to reach its goal," says space law attorney Michael Listner, a writer forThe Space Review. "Adding the Chinese orbiter late seems to have pushed the risk to the mission very, very high."
After weeks of attempts to re-establish radio communications by European Space Agency and NASA transmitters, and fleeting hints of contact, Russian space agency officials declared the craft a loss. Based on U.S. Strategic Command reports of the satellite's steadily declining orbit— falling from a low point of 130 miles high to 114 miles now — the 29,100-pound spacecraft, stuffed with 8.3 tons of hydrazine fuel, will likely come down around Jan. 15, the Russian Defense Ministry has concluded.
Mars has a habit of claiming overly-thrifty probes. NASA's Mars Polar Lander, a $120 million spacecraft, was judged about 30% underfunded by an accident panel after its calamitous crash in 1999 most likely caused by landing rockets failing to fire. Double-checks of components and testing often go by the wayside as budgets get tight with space missions.
"The Phobos-(Grunt) science team would like to repeat the mission using (the) experience that we got working on this mission," said mission scientist Alexander Zakharov of the Space Research Institute in Moscow, by e-mail. However, he adds any decision will be up to ROSCOSMOS, the Russian space agency, which is expected to conclude an accident investigation this month.
All told, Russia looks likely to go 1-for-20 in successful Mars missions with the failure of Phobos-Grunt, a blow to a space program that analyst Bertrand de Montluc of France's Centre for the Study of International Relations called "resurgent" in a 2010 Space Policy journal report. But he also noted then that funding for the Russian space agency, averaging about $950 million a year, looked "weak." Now that weakness seems to have caught up to ROSCOSMOS.
On the other hand, a cheaper aluminum fuel tank used on Phobos-Grunt may alleviate the worst fears about its re-entry. "Aluminum has a very low melting temperature and rarely survives re-entry," says space debris expert Nicholas Johnson of NASA's Johnson Space Center in Houston. Fears about the dangers of toxic fuel surviving re-entry played a role in the U.S. shoot-down of the malfunctioning USA-193 spy satellite in 2008. But that looks unnecessary for Phobos-Grunt, Listner says. "Russia is still legally responsible, in my opinion, for any damages the satellite causes."
The satellite could land anywhere from 51.4 degrees north latitude, about as far north as London, to 51.4 degrees south latitude, nearly as far south as the tip of South America.
While the U.S. Defense Department has not performed its own estimate of the re-entry date for Phobos-Grunt, Johnson notes, most amateur observers agree with the Russian analysis, predicting a re-entry somewhere from Jan. 14 to Jan. 17.
When it comes down, Phobos-Grunt will join two other large spacecraft that have fallen from the sky in recent months. NASA's UARS satellite landed in the Pacific Ocean in September, and Germany's ROSAT plunged into the Bay of Bengal in October. Slowed by atmospheric drag, the satellites dropped their orbital heights daily, until at about 80 miles altitude, the thicker atmosphere triggered a fiery plunge across the sky.
"Satellites fall down all the time. But these were all sizable ones, which along with the initial fuel concerns explains a lot of the interest," Listner says.
Less noticed, the U.S. Air Force pulled off a daring rescue of its $2 billion AEHF-1 communications satellite, Air Force Magazinerevealed this month. With a main rocket fuel line clogged, aerospace engineers fired maneuvering rockets hundreds of times to boost the bird to a 22,000 mile-high circular orbit, a months-long task that used the positioning thrusters in ways never intended.
About the only bright spot for the Phobos-Grunt mission, Listner says, is the international cooperation it elicited in attempts to rescue the spacecraft, already built with contributions from 12 nations. "It is pretty amazing that Russia relied on U.S. Air Force data in its discussion of the satellite's likely re-entry date," Listner says. "That wouldn't have happened during the Cold War."
So there is still plenty of hope for Mars, with NASA's $2.5 billion "Curiosity" rover about 210 days away from a landing on the Red Planet. And the European Space Agency's help with attempts to re-contact Phobos-Grunt may have bought it some goodwill from Russia, seen as a possible partner on the 2018 ExoMars rover aimed at looking for traces of life on the Red Planet. "Mars is not easy," Listner says. "Why not look for help."
News source:usatoday
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