Meteorites traced to origins in asteroid belt

Astronomers have traced several meteorites that fell to Earth back to their origins in the main asteroid belt, which is located between Mars and Jupiter. This research began ten years ago, with efforts from NASA and the SETI Institute to map the asteroid belt. To do this, they created the Global Fireball Observatory, a network of cameras worldwide to track meteorites as they entered Earth’s atmosphere. Peter Jenniskens, one of the project founders, described it as a long-term detective story that has begun to reveal a geologic map of the asteroid belt. The team tracked the paths of 17 meteorites and published their findings recently. Meteorites are remnants from space that survive the trip through Earth’s atmosphere. Most come from the asteroid belt, which contains over a million asteroids dating back 4.5 billion years. These asteroids are fragments left over from the formation of planets. Astronomers can determine the age of meteorites by measuring radioactive elements and comparing them to the ages of asteroid debris fields. The spread of these asteroids can indicate how long ago they were disrupted. The research has identified 75 meteorites from the asteroid belt. One key discovery involved ordinary chondrite meteorites, or H chondrites, which are common and hold valuable information about the early solar system. The team found that many originated from a debris field called Koronis. They also tracked the ages of different groups of meteorites. For example, H-chondrites from the Nele family are about 6 million years old, while some L chondrites find their roots in a major collision that happened 468 million years ago. This study provides a detailed map of the asteroid belt, but there is still much to learn. The researchers view this as just the beginning of their exploration. They look forward to uncovering more about the origins of meteorites as more falls are observed in the future.