In 2019, the solar system welcomed its second interstellar guest, Comet 2I/Borisov. These rare encounters offer astronomers an invaluable chance to study material from other star systems.

Astronomers on Wednesday confirmed the discovery of an interstellar object racing through our solar system—only the third ever spotted, though scientists suspect many more may slip past unnoticed.

Earlier this month astronomers were thrilled to discover only the third known interstellar object ever seen in our solar system. It will reach about the orbit of Mars before it boomerangs back ...

An interstellar object called 3I/ATLAS is passing through our solar system this year, NASA announced yesterday. Today at 6 p.m. ET, you can see it for yourself, thanks to a livestream from the ...

An "interstellar object" is speeding toward the inner solar system, where Earth is located, astronomers have confirmed. The object -- likely a comet -- was first detected in data collected between by ...

A diagram shows the trajectory of interstellar Comet 3I/ATLAS as it passes through the solar system. It will make its closest approach to the sun in October. Late in the evening on July 1, a ...

The speed and trajectory of the object A/2017 U1 suggested that it did not come from our Solar System, and that it will leave our Solar System again. ‘Oumuamua, as it is now called, was our ...

The first step in rigorously investigating this question is to calculate a capture cross section for interstellar objects as a function of hyperbolic excess velocity, which can be convolved with ...

"We concluded that, in the outer reaches of the solar system, and even considering the large uncertainties associated with the abundance of Borisov-like objects, transitory interstellar comets ...

One less conventional explanation: if Harvard astronomer Avi Loeb is to be believed, the 300-to-3,300-feet-long object could be an alien "mothership " visiting the solar system from lightyears away.

An "interstellar object" is speeding toward the inner solar system, where Earth is located, astronomers have confirmed. The object -- likely a comet -- was first detected in data collected between ...