What To Know
- Astronomers have captured what appears to be a snapshot of a massive collision of giant asteroids in Beta Pictoris, a relatively young nearby star system in the midst of planet formation.
- Recently, focusing on the heat emitted by crystalline silicates (minerals commonly found around young stars as well as on Earth and other celestial bodies) with the telescope James Webbscientists found no trace of these previously observed particles.
- We believe that large collisions like this must have occurred in our Solar System at a similar age as part of the formation process of terrestrial planets.
Astronomers have captured what appears to be a snapshot of a massive collision of giant asteroids in Beta Pictoris, a relatively young nearby star system in the midst of planet formation. Astronomers believe the event may have resulted from the impact of planetesimals on their way to forming planets, perhaps even rocky ones similar to Earth, Mars or Venus.
A rare observation
Nearly twenty years ago, astronomers observed a huge cloud of fine dust particles around a young star located just 63 light years from Earth with the Spitzer telescope. Recently, focusing on the heat emitted by crystalline silicates (minerals commonly found around young stars as well as on Earth and other celestial bodies) with the telescope James Webbscientists found no trace of these previously observed particles. In other words, the dust cloud had mysteriously disappeared. To explain this observation, the researchers suggest that a collision occurred between asteroids or other large objects around this star about twenty years ago, pulverizing the bodies into fine dust particles. Initially, this dust close to the star would have heated up to emit thermal radiation identified by Spitzer’s instruments. The new data suggest that this dust is not more detectableas it is scattered outward by the radiation from the system’s central star. Christine Chen, an astronomer at Johns Hopkins University and lead author of the study, emphasizes the importance of this observation: “Beta Pictoris is in a phase of planet formation where collisions of giant asteroids contribute to the creation of rocky planets. What we are observing here is the real-time formation process of these planets and other celestial bodies.”
Infrared emission from Beta Pictoris as seen by Spitzer and the James Webb telescope. Credit: Roberto Molar Candanosa/Johns Hopkins University
A cataclysmic collision linked to asteroids
The magnitude of the collision is impressive. It would have released a quantity of dust equivalent to approximately 100,000 times that of the asteroid responsible for the extinction of dinosaurs non-avian. This suggests, the researchers say, that the collision likely involved a Vesta-sized asteroidthe second most massive body in the main asteroid belt (530 kilometers in diameter). We believe that large collisions like this must have occurred in our Solar System at a similar age as part of the formation process of terrestrial planets. However, despite the already confirmed presence of two gas giant planets around Beta Pictoris, no terrestrial planets have yet been identified. This fascinating discovery in any case highlights once again the power of infrared observation enabled by the James Webb telescope. The research was presented by Chen at the 244th Meeting of the American Astronomical Society in Madison, Wisconsin.
