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

(www.abc.net.au)
306 points gammarator | 10 comments | 03 Jul 25 03:19 UTC | HN request time: 1.062s | source | bottom

Minor Planet Electronic Circular: https://minorplanetcenter.net/mpec/K25/K25N12.html
1. andrewstuart ◴[03 Jul 25 11:33 UTC] No.44453935[source]▶
They’re always coming through.

The solar system is an interstellar highway.

Chariots Of The Gods, man.

But seriously, why would interstellar objects come towards our solar system?

It seems strange. Does gravity do that?

If there’s two within ten years then there has to be a veritable swarm of these things traveling between the stars - is that right or wrong?

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2. Jyaif ◴[03 Jul 25 12:56 UTC] No.44454532[source]▶
A very rough calculation would suggested that the cylinder that goes from our solar system to Proxima Centauri contains 5000 similarly sized objects moving at the same speed:

1 object crossing the solar system plane every 5 years at 60km/s

+

Proxima Centauri is approximately 5 light years away

=>

there are `speed of light / 60km/s` objects in the cylinder.

3. hermitcrab ◴[03 Jul 25 15:17 UTC] No.44455929[source]▶
Objects can get flung out of solar systems when they pass close to large objects. Similar to how spacecraft get gravity assists.
4. alganet ◴[03 Jul 25 18:03 UTC] No.44457662[source]▶
> But seriously, why would interstellar objects come towards our solar system?

Why wouldn't they?

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5. coolspot ◴[03 Jul 25 18:54 UTC] No.44458112[source]▶
Because to go through plane like that they need to match our solar system speed relative to galaxy.
replies(1): >>44458261 #
6. alganet ◴[03 Jul 25 19:10 UTC] No.44458261{3}[source]▶
Universe is big and full of random small rocks floating around everywhere.

Why should I believe some object was _intentionally_ thrown here? Maybe it is just one of those random rocks.

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7. andrewstuart ◴[03 Jul 25 19:59 UTC] No.44458661[source]▶
Because space is big. Really really big.
replies(1): >>44458859 #
8. alganet ◴[03 Jul 25 20:22 UTC] No.44458859{3}[source]▶
The ocean is big compared to a fish, but I can still find fish in it quite easily.

There's nothing statistically weird about these interstellar objects.

9. typeofhuman ◴[04 Jul 25 01:55 UTC] No.44460520{4}[source]▶
> Floating around everywhere.

Sorry to be pedantic. But space is really, really, really... empty. That's why the best name for it is, space.

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10. alganet ◴[04 Jul 25 02:13 UTC] No.44460589{5}[source]▶
You can go outside at night and see big rocks floating. If space is so empty, how is it possible that you can see them with your own eyes?

We live in a patch of space that's not that empty. Maybe that interstellar rock floated from other patch of space that's not that empty all the way over here, all on its own.

Most rocks we see in our patch of space, as far as we can possibly know, were not intentionally launched.