Mission to Mars moon could be a sample-return twofer, study says

The Martian moon Phobos has accumulated dust and debris
from the surface of Mars, knocked into its orbital path by
projectiles colliding with the planet. A sample-return
mission to Phobos would thus return material both from
Phobos and from Mars. Credit: NASA

The study helps to confirm the idea that the surface of Phobos contains tons of dust, soil, and rock blown off the Martian surface by large projectile impacts. Phobos' orbital path plows through occasional plumes of Martian debris, meaning the tiny moon has been gathering Martian castoffs for millions of years. That means a sample-return mission planned by the Russian space agency could sample two celestial bodies for the price of one.

Read more at: http://phys.org/news/2013-11-mission-mars-moon-sample-return-twofer.html#jCp