The Phobos-Grunt?spacecraft launched from Russia this week destined for Mars has yet to leave Earth orbit ? and looks increasingly likely to tumble back to Earth with its full tanks of toxic fuel.
A spacecraft launched from Russia last Wednesday and originally destined for Mars has yet to leave Earth orbit ? and looks increasingly likely to tumble back to Earth over the next several weeks.
Skip to next paragraphThe craft, Phobos-Grunt (Phobos Soil), was to have traveled to Mars' moon Phobos to gather and return to Earth samples of the moon's soil and rocks. But once the craft reached Earth orbit, motors in the rocket stage that would have set Phobos-Grunt on its path to the red planet failed to ignite.
Engineers with Roscomsos, the Russian Federation Space Agency, have tried to communicate with the craft in hopes of igniting the motors before changes to the orbits of Earth and Mars close the window of opportunity over the next few days.
But according to updates on the website RussianSpaceWeb.com, all attempts have failed so far. If efforts to send the mission on its way fail, the craft ? brimming with a load of toxic fuel in tanks that potentially could survive reentry ? could reenter Earth's atmosphere at the end of the month.
Russia's travails serve as a fresh reminder that space exploration is hard.
"That's why it's called rocket science," says Ralph McNutt, chief scientist at the Johns Hopkins University's Applied Physics Laboratory in Laurel, Md., and the project scientist for NASA's Messenger mission, whose spacecraft currently is orbiting Mercury.
It's a point not lost on Mars-mission planners at NASA, who are preparing to launch the $2.5-billion Mars Science Laboratory Nov. 25.
Phobos-Grunt and the Mars Science Laboratory represent the most ambitious Mars-exploration missions to date for their respective space agencies.
The lab is a 1-ton rover loaded with instruments to analyze Martian rocks and soil within a vast feature dubbed Gale Crater. Although the rover isn't designed to hunt for life, it will be hunting for organic compounds that would help determine whether the planet had conditions that could have supported life.
In one sense, the world's space agencies have a success rate at the Mars-mission plate that major-league ball players would envy. Since 1960, when the then-Soviet Union launched the first mission to the red planet, which failed, 35 launches by four nations have amassed a .329 average, based on NASA's tabulation of international Mars launches.
But that average masks a wide disparity in success rates among the four.
With the apparent failure of Phobos-Grunt, Russia is 0 for 17 attempts since 1960 at a mix of Mars flybys, orbiters, and landers.
Japan, which launched a Mars orbiter in 1998, is 0 for 1. Europe, with its inaugural Mars Express/Beagle 2 orbiter-lander combo, is 0.5 for 1 at the red planet. Launched in 2003, the duo reached Mars. The orbiter has been a science success, and its mission has been extended to 2014. But the lander was declared lost after repeated attempts to contact it failed following its December 2003 descent to the surface.
NASA, meanwhile, has enjoyed 11 successful Mars missions out of 16 launched since 1964, including flybys, orbiters, and rovers.
It's easy to get used to those successes, but they are far from assured.
Designing craft for interplanetary travel means tailoring its systems to function for years in an environment far different from the conditions craft encounter in Earth orbit, where designers have far more experience, Dr. McNutt says.
Flitting between Earth and anywhere else exposes a craft and its sensitive electronics to the potentially disruptive effects of cosmic rays.
Pick your destination and you will encounter much different contrasts in temperatures the craft must endure, compared with conditions at Earth. Think the Voyager spacecraft at the far edges of the solar system versus the Messenger mission orbiting Mercury.
Indeed, the combination of the vacuum of space and temperature can be a mission-ender, he says, citing NASA's Mariner 3 mission as an example.
Launched in 1964, it was the US's first attempt at a Mars flyby. But the craft ultimately failed, felled by the combined effects of vacuum and temperature ? something for which it was not tested prior to launch. Engineers conducted vacuum and temperature tests separately.
The failure led to the development of test chambers that could replicate both conditions simultaneously, McNutt says.
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