14 DAY TRIAL // Despite the failure of the Phobos-Grunt mission, the Russian Federal Space Agency (RosCosmos) seems bent on sending a spacecraft in orbit around the Martian moon Phobos. A successor to the failed spacecraft is being proposed, with a launch date tentatively scheduled for 2020.
Phobos is really small when compared to our Moon. It features a mean radius of 11.1 kilometers (6.9 miles), a volume of 5,680 cubic kilometers (1,360 cubic miles) and a surface area of just 6,100 square kilometers (2,400 square miles). Despite these dimensions, Phobos is about 8 times larger than the other Martian moon, Deimos.
RosCosmos attempted to launch the Phobos-Grunt mission towards the Red Planet on November 8, 2011, but a series of failures stranded it in low-Earth orbit. Eventually, its orbit decayed until it burned up high in Earth's atmosphere, on January 15, 2012.
Now, the Russian agency plans to build another spacecraft for exploring Phobos. Early plans call for the vehicle to be launched as early as 2020. The Phobos-Grunt 2 mission will feature an improved version of the spacecraft, as well as a sample-return component, Universe Today reports.
Engineers say that a small lander outfitted with a return stage could be deployed from the orbiter, collect samples from the surface of Phobos, and then return them to scientists on Earth for study and analysis. Obtaining Martian samples is a holy grail for planetary scientists.
Studying Phobos would provide scientists with a wealth of data, since the moon periodically passes through plumes of material that have been ejected from the Martian surface by ancient asteroid or comet impacts. These materials therefore lie on the surface of the small satellite.
“When an impactor hits Mars, only a certain of proportion of ejecta will have enough velocity to reach the altitude of Phobos, and Phobos’ orbital path intersects only a certain proportion of that,” explains Brown University planetary geosciences group member Kenneth Ramsley.
“So we can crunch those numbers and find out what proportion of material on the surface of Phobos comes from Mars,” he adds. What is at stake here is figuring out if Phobos was formed by aggregating space debris following an impact, or if it is an asteroid caught in orbit around Mars.
“Only recently – In the last several 100 million years or so – has Phobos orbited so close to Mars. In the distant past it orbited much higher up. So that’s why you’re going to see probably 10 to 100 times higher concentration in the upper regolith as opposed to deeper down,” the expert says.