
The Odd Behavior of Interstellar Object 'Oumuamua, Explained
It wasn't aliens after all — an astrochemist and an astronomer have teamed up to explain why the interstellar object 1I/'Oumuamua behaved the way it did.

Was Interstellar Object `Oumuamua a Chunk of Exo-Pluto?
The interstellar pancake named 'Oumuamua might have been a chip off a Pluto-like object in another star system.

Can This Near-Earth Asteroid Help Us Understand the First Interstellar Visitor?
Astronomers have observed an object like ‘Oumuamua — but unlike the first known interstellar visitor, this one is in the solar system.

Can We Expect Seven Interstellar Visitors Per Year?
A new study estimates the number of interstellar objects that fly through the inner solar system every year, and it could be quite a lot.

The Origins of Interstellar Objects
The first two interstellar visitors to the solar system are finally shedding light on their places of origin.

Another Interstellar Visitor Is Headed Our Way
An amateur astronomer has discovered a comet that might be the second interstellar visitor after 'Oumuamua — and it's heading for its closest approach to the Sun late this year.

Was ‘Oumuamua a Fragment from a Disintegrated Comet?
A new study suggests that ‘Oumuamua’s strange trajectory back out to interstellar space can be explained if the object had the density of air.

‘Oumuamua "Sped Up" in the Inner Solar System. This Might Be Why.
Astronomers think a jet-powered rocking motion could solve the puzzle.

'Oumuamua’s Story Keeps Spinning
Two new studies question the cometary nature of 'Oumuamua, our first interstellar visitor, and where in the Galaxy it might have come from.

'Oumuamua Was a Comet After All
Researchers have found that 'Oumuamua — the first confirmed object to enter the solar system from interstellar space — was a comet, releasing just enough gas to subtly change its course.

Is ‘Oumuamua an Interstellar Pancake?
A new analysis of more than 800 telescopic observations suggests that our first known interstellar visitor could have the shape of a cigar or a fat disk.

`Oumuamua: Red, Tumbling, and Silent
Astronomers' recent observations of our first-known interstellar visitor reveal that it is very strange indeed.

Meet 'Oumuamua, the Interstellar Cigar
Rapid-response observations by major observatories shows that the first-known interstellar visitor is 10 times longer than it is wide.

Update on `Oumuamua, Our First Interstellar Object
The arrival of an object from beyond the solar system caught astronomers by surprise — but that doesn't mean that they were unprepared to study it.

Astronomers Spot First-Known Interstellar "Comet"
Telescopes only picked it up a week ago, but it's likely been traveling through interstellar space for millions of years.