An anonymous reader writes "Washington University in St. Louis space scientists are reporting the first definitive laboratory dissection of an interstellar dust particle, thus pulling out each grain's history individually. When collected at high-altitude, the origin of six grains are from outside our solar system. 'Space' is full of dust, or ejected material from long-dead stars. In this case, 3 of the 6 dust grains are from red giant stars, and perhaps 2 are from supernovae. In the next 5 years, there are six missions targeting a rendezvous with either a comet or asteroid, including the Stardust mission to return the first extraterrestrial samples since Apollo. That only leaves 100 billion comets left to explore in our own solar system's Oort cloud." Update: 02/28 17:22 GMT by M : Fixed university name.