Astronomers discover 3I/ATLAS – Third interstellar object to visit Solar System

Summary

For only the third time in history, astronomers have discovered a new interstellar object that originated from outside our Solar System.The object, known as 3I/ATLAS, is likely a comet and is much faster than any other interstellar object found before. The object appears to be hurtling towards our Sun at about 60 kilometres a second. "This thing is coming in at such an incredible speed that absolutely nothing in the Solar System could have caused this," Jonti Horner, an astronomer at the University of Southern Queensland, said. "Of the three interstellar objects we have seen, this is by far the fastest."There are only two other interstellar objects that have previously been tracked entering our Solar System — 'Oumuamua and Comet 2I/Borisov."It's so exciting," Professor Horner added.Rumblings of the potential interstellar object started in astronomy groups when the object was first detected early this week."It has been picked up so early — relatively speaking — that we've got at least eight months [during which] we'll be able to observe it," he said.How was 3I/ATLAS found?The object was first detected by the ATLAS telescope in Chile on 1 July.Follow-up observations confirmed the orbit was extremely unusual — almost unaffected by the Sun's gravity, Professor Horner said. "Plotting the orbit of this thing [shows] it barely bends as it goes past the Sun."The trajectory of interstellar comet 3I/ATLAS as it passes through the Solar System. (Supplied: CSS, D. Rankin / CC BY-SA 4.0 / Olivia Willis)But it wasn't until yesterday that scientists at the Minor Planet Centre in the US confirmed the object was an interstellar object.They also suggested the object was likely a comet, due to images that showed it had a short tail.More observations will need to be done to confirm this, and get more detail about the object.However, because 3I/ATLAS has been found so early, astronomers will have plenty of time to track it as it moves through the Solar System.When will 3I/ATLAS be close...