Cosmochemistry frequently involves direct measurement of physical samples in laboratories on the Earth. Samples are most often meteorites and micrometeorites, which include material that originated on the Moon, Mars, many different asteroids, and quite possibly comets, as well as with samples returned from the Moon by manned and robotic missions. Other materials available for direct study by cosmochemists are tiny particles from Comet Wild 2 returned to Earth in 2006 by NASA's Stardust mission, and samples of solar wind, captured by the Genesis mission and returned to Earth in 2004. The most exotic available samples are tiny presolar grains that are embedded in some primitive chondritic meteorites, which originated elsewhere in the galaxy prior to the formation of the solar system. Similar interstellar dust particles may also have been collected by the Stardust mission, although this has not yet been confirmed.
NASA has funded a research program in Cosmochemistry since the 1970s