Aug 24, 2021 - Science

Interstellar objects are everywhere

Comet Borisov as seen by the Hubble Space Telescope. Photo: NASA/ESA

Comet Borisov as seen by the Hubble Space Telescope. Photo: NASA/ESA

Interstellar comets and asteroids might be more common in our solar system than previously expected, new research suggests.

Why it matters: These special objects can give scientists a glimpse into the compositions of other star systems without ever leaving our own, helping astronomers understand just how unique — or mundane — our own star and its planets may be.

Driving the news: The new study — in the journal Monthly Notices of the Royal Astronomical Society — posits that interstellar objects in the Oort Cloud, the mass of cold objects that orbit the Sun from up to 1 trillion miles away, outnumber those that originate in the solar system.

  • The scientists behind the new work used calculations they built off of observations of the Comet Borisov, the first known interstellar comet discovered in 2019.
  • "Before the detection of the first interstellar comet, we had no idea how many interstellar objects there were in our solar system, but theory on the formation of planetary systems suggests that there should be fewer visitors than permanent residents," one of the authors of the new study Amir Siraj, of the Center for Astrophysics, said in a statement.
  • "Now we’re finding that there could be substantially more visitors."

Yes, but: The new conclusions are based on limited data, so more research is needed before scientists can know for sure what's going on in the Oort Cloud.

  • However, the study does point to the idea that it might be easier to study interstellar objects than initially thought.

What to watch: The Vera Rubin Observatory, expected to come online in 2022, will be able to find plenty of new interstellar objects coming through our solar system in the future.

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