Mike Olson6d ago
Corey S Powell

Astronomers have discovered 11 more moons around Saturn, bringing its total to 285--by far the most of any planet in the solar system.

The true number may be unknowable, if you count every ring particle as its own little moon.

https://minorplanetcenter.net/mpec/K26/K26F14.html #space #science #nature #math

Mar 17 at 2:14pmWeb
Show threadGuillotine Jones, Flâneur6d ago
@coreyspowell
Would I get into trouble if I were to state,
"Now do that for Uranus"?
Show threadStarkRG6d ago
@coreyspowell Yeah, I think we might need a scientifically useful definition of a moon to go with the currently scientifically useless definition of a planet.
Show threadDavid W. Jones6d ago
@StarkRG @coreyspowell PLUTO IS A PLANET. Now get off my hill.
Show threadStarkRG6d ago
@dancingtreefrog @coreyspowell I honestly don't care whether the definition include Pluto, I think it probably should, but what I really care about is that it be a *useful* definition, not one mired in legacy. The existing definition is both too narrow (it doesn't include rogue planets or planets orbiting other stars) and too broad (gas giants should absolutely not be in the same category as rocky planets, and ice giants should probably be considered a different category from normal gas giants).
Show threadStarkRG6d ago
@dancingtreefrog @coreyspowell Pluto, Titan, and even Ceres have more in common with Earth than it does with Jupiter or Neptune. Maybe stop using the word "planet" entirely, and use "world" for things you could theoretically go to and walk around on without accidentally reaching escape velocity. World is a perfectly cromulent word and does the job of putting in our mind the idea of a place we could go and exist. Even with floating habitats, Jupiter is different enough to not really be a world.
Show threadDavid W. Jones6d ago

@StarkRG @coreyspowell I agree, although probably many people think of "world" as one that has life.

Also: what about dual planets orbiting each other, or near-duals like the Earth-Moon system?

Show threadStarkRG6d ago
@dancingtreefrog @coreyspowell I dunno, when astronauts walked on the Moon, they often remarked that it was a world with it's own stark beauty. Looking at pictures of the surface of Mars, Titan or Venus always make me think "world." Even if the environment would kill us instantly, we can imagine walking around there. Gas and ice giants much less so, though more than stars. Large enough asteroids and comets could be worlds too. Too small and they're just rocks, even if they're mountain-sized.
Show threadDavid W. Jones3d ago
@StarkRG @coreyspowell I think maybe the concept or feeling of "world" is built directly on personal experience or indirectly on learning about someone else's personal experience?
Show threadStarkRG3d ago
@dancingtreefrog @coreyspowell Is that any different from other words and concepts?
Show threadDavid W. Jones2d ago
@StarkRG
Probably not. Although someone such as a child raised on a "mountain-sized rock" might think of it as a world while an adult might see it as a rock.
@coreyspowell
Show threadDavid W. Jones6d ago

@StarkRG @coreyspowell I agree that rogue planets and planets orbiting other stars should be included. At least categorize them as planets even if we can't specifically classify one as rocky/ice/giant.

I still wonder if there aren't cores of rocky planets hiding within gas giants and ice giants.

Is the difference between gas and ice planet simply their distance from their star?

Show threadStarkRG6d ago
@dancingtreefrog @coreyspowell I think the consensus among astrophysicists is shifting away from Jupiter having a rocky core. I'm not sure about Saturn. But even if they did, the rocky core wouldn't be anything like an actual rocky planet, it would be more like our own solid metal core, pretty much perfectly spherical.
Show threadKevin Russell6d ago

@coreyspowell

Its not a moon unless it clears its local are of moonlets.

Show threadRead along with Matt6d ago

@coreyspowell wait there are moons inside the rings of saturn?? how are they not torn apart by tidal forces when something else clearly was torn apart by tidal forces exactly that distance from the planet? are saturn’s rings simply a moon that failed to “get good”?

edit: oops, never mind, my bad, didn’t realize those were rings labels, not moons

Show threadCodey McCodeface6d ago
@coreyspowell Most of them are dwarf moons. You can tell because they’re always singing songs about gold.
Show threadEye6d ago

@coreyspowell

Was Prof. Lawler and team involved in this discovery too?!

Show threadSpace Catitude 🚀6d ago

@coreyspowell

Yeah. That's a bit like the "coastline problem", really.

Show threadC.S.Strowbridge6d ago

@coreyspowell "The true number may be unknowable, if you count every ring particle as its own little moon."

There needs to be a definition that separates true moons from minor satellites.

Show threadatopoeia-o6d ago
@coreyspowell Yez Earth is such a slcaker.
Show threadgunstick5d ago
@coreyspowell ah, good to know that saturn does not store the amount of moons in a 8 bit byte (max 255 moons).