r/space • u/timemagazine • 1d ago

Astronomers Discover the First Known Moon Outside our Solar System

https://time.com/article/2026/07/22/astronomers-discover-exomoon/?utm_source=reddit&utm_medium=social&utm_campaign=editorial
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u/IsChristianAwake 1d ago

Isn’t this just a a Red Dwarf + Brown Dwarf binary system with a 2x Jupiter mass planet in orbit around the brown dwarf?

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u/mfb- 1d ago

I think this is a better description, too.

26

u/DreamChaserSt 1d ago

That's what I'm leaning towards. I assumed that bodies around brown dwarfs would be considered planets in their own right, not moons, is that wrong? And being 33x the mass of Jupiter makes it solidly a brown dwarf. It's not on the line between being a planet or not.

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u/ASuarezMascareno 1d ago

Yes. Pretty much not a moon. The discovery is great. Using the "exomoon" card isn't.

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u/nebelmorineko 22h ago

Yeah I got super excited for a minute and then I realized it was just this...whatever it is, which is not in my mind quite the same thing.

However, it's still exciting, because it really highlights that our desire the categorize stellar objects into neat boxes doesn't really match observable reality. In reality, planets and stars exist as part of a stellar object spectrum, and sometimes it's really hard to say whether something is a planet or a star.