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interstellar visitor · interstellar visitor passing through

2I/Borisov

Borisov was the second visitor from another star, and this one was a proper comet with a tail — made of ice that has never once been warmed by our Sun! It is still leaving, and it is not coming back.

🚀 Travel there
2I/Borisov — Drawn, not photographed.

What it is

Second confirmed interstellar object, a true comet with unusually high carbon monoxide.

Interstellar visitor: Passing through from another star, never to return. Every kind of thing there is →

Can you see it?

No. No telescope on Earth will show you this one; it is here to be understood, not seen. It is here because it is worth knowing about — and because leaving it out would make the sky look emptier than it is.

Worth knowing about 2I/Borisov

What it is made of
A true comet, with a glowing coma and tail, chemically similar to solar system comets but with unusually high carbon monoxide.
What makes it worth knowing
Discovered August 2019 by an amateur astronomer in Crimea.
How did anyone measure the Earth in the first place?
The numbers
Across1 km
Found in2019

What it belongs to

☀️ Everything the Sun holds, in one place📖 How the solar system fits together

Then go outside

Not this one. But the sky over your head is full of ones you can see, and the Planetarium knows which.

🌙 Plan an evening outside🌌 Everything else in the sky