Russia's Phobos-Grunt probe, which had been slated to head off this year on a sample-return mission to Phobos, the larger of Mars's two moons, will not launch until at least 2011, according to the Russian Interfax news agency.

Citing "a source in Russia's space industry," the news agency reported that the Russian Federal Space Agency and the Russian Academy of Sciences would make the postponement official in the next few days. As noted in a recent feature article about the Phobos-Grunt mission on, the delay has been rumored for months.

As was the case with NASA's mammoth rover, the Mars Science Laboratory, pushing a mission start date back from late 2009 requires a lengthy delay. The launch window to the Red Planet and its environs, based on the relative positions of Earth and Mars, only comes about every 26 months or so.

Aside from returning soil samples from Phobos, the probe is designed to ferry a collection of living organisms—bacteria, yeast, and tiny invertebrates called tardigrades among them—to Mars orbit and back. The LIFE experiment, spearheaded by the California-based Planetary Society, would assess the deep space environment's effects on living things, testing the theory that life might have shuttled between planetary bodies on asteroids or comets.

Bruce Betts, the LIFE experiment manager for the Planetary Society, says that no official word has reached his organization yet on Phobos Grunt's fate. "We know a possible delay has been under serious consideration, but so has a launch this year," Betts says. "Regarding LIFE, obviously human nature makes us want it to fly sooner rather than later, but it is far more important to take the time to prepare a successful mission."

Image of Phobos: NASA