Extraterrestrial materials

Extraterrestrial material refers to natural objects now on Earth that originated in outer space. Such materials include cosmic dust and meteorites, as well as samples brought to Earth by sample return missions from the Moon, asteroids and comets, as well as solar wind particles. Extraterrestrial materials are of value to science as they preserve the primitive composition of the gas and dust from which the Sun and the Solar System formed. Extraterrestrial material for study on earth can be classified into a few broad categories, namely: Meteorites too large to vaporize on atmospheric entry but small enough to leave fragments lying on the ground, among which are included likely specimens from the asteroid and Kuiper belts as well as from the moon and from Mars. Moon rocks brought to Earth by robotic and crewed lunar missions. Cosmic dust collected on Earth, in the Earth's stratosphere, and in low Earth orbit which likely include particles from the present day interplanetary dust cloud, as well as from comets. Specimens collected by sample-return missions from comets, asteroids, solar wind, which include "stardust particles" from the present-day interstellar medium. Presolar grains (extracted from meteorites and interplanetary dust particles) that predate the formation of the Solar System. These are the most pristine and valuable samples. Examples of extraterrestrial material collected on Earth include cosmic dust and meteorites. Some of the meteorites found on Earth had their origin in another Solar System object such as the Moon, Martian meteorites, and the HED meteorite from Vesta. Another example is the Japanese Tanpopo mission that collected dust from low Earth orbit. In 2019, researchers found interstellar dust in Antarctica which they relate to the Local Interstellar Cloud. The detection of interstellar dust in Antarctica was done by the measurement of the radionuclides Fe-60 and Mn-53 by highly sensitive Accelerator mass spectrometry, where Fe-60 is the clear signature for a recent-supernova origin.