The European Space Agency (ESA) is considering a space mission called Marco Polo, in which a spacecraft would land on a small asteroid, drill into its surface to collect samples of rock and dust, and then fly back to Earth where it would drop its sample capsule down to the surface. Two satellite manufacturing companies are currently conducting a feasibility study; if ESA signs off on the proposal, Marco Polo could sail off into space in 2017.
Asteroids are chunks of debris left over from the chaotic mass that spun around the young Sun during the formation of the Solar System about 4.6 billion years ago. The rest of the material coalesced into planets [The Daily Mail]. Researchers say that studying the composition of an asteroid could give them insight into how the solar system formed. The roughly $430 million mission would also serve as a warm-up for a hypothetical round-trip journey to Mars, as it would enable the development of technology needed for getting up and down from a large planetary body with a much bigger gravitational pull [Telegraph].
Marco Polo would not be the first spacecraft to alight on an asteroid, or to try to bring back a souvenir from one. In 2001, NASA brought the NEAR Shoemaker spacecraft down for a landing on the nearby asteroid Eros, from where it continued to send data for about two weeks. Landing can be tricky, though: In 2005, Japan’s Hayabusa spacecraft attempted to land briefly on the Itokawa asteroid and collect a rock sample, but malfunctions and communication blackouts bedeviled the mission. Still, Japanese engineers believe Hayabusa collected some dust that swirled up from the asteroid’s surface, and are eagerly awaiting the craft’s return to Earth in 2010.
While robotic rovers and probes have conducted many noteworthy experiments on extraterrestrial bodies, so-called sample return missions are of increasing interest to scientists. Although in-situ measurements provide remarkable insights, so much more would be learnt if materials were brought back to Earth laboratories, where the full panoply of modern analytical technologies can be deployed [BBC News]. ESA and NASA have also discussed cooperating on a sample return mission to Mars, although the $4.5 to $8 billion price tag for such a mission is daunting.
Image: EADS Astrium