kichae

typotyper@sh.itjust.works said in How fast is that in kilometers per hour?: So you’re saying as our own system ages the planets will get pulled in and eaten up.

Not in the same way, no. None of our planets are touching the Sun's atmosphere in the same way this planet is, and none of them are orbiting at rates that are faster than the Sun's rotation. If anything, tidal interactions would want to speed up the planet's orbits, and push them into higher orbits.

But eventually the Sun will become a red giant star, which will change some of these relationships. We will see competing effects then: The Sun will begin shedding its outer layers, which will create a higher drag environment for the planets (that were not swallowed during the Sun's expansion) which would tend towards inward migration, but this will also lower the Sun's mass, which will lend itself toward an outward migration.

typotyper@sh.itjust.works said in How fast is that in kilometers per hour?: Would Jupiter being a gas giant get slowed down equally to the outer planets or would it eat some planets on its own.

All of the outer planets are gas giants.

Jupiter is not currently migrating inward, nor are any of the other planets. If inward migration happens after the Sun becomes a red giant, those other outer planets will not get anywhere close to it. As a red giant, the Sun will approximately fill Earth's orbit. Jupiter's orbit is 5x larger than this; Saturn's is 10x larger, and by the time the Sun actually grows this large, all of the planets' orbits will be even larger than they are today, thanks to gradual mass loss.

None of the outer planets are expected to fall into the Sun at any point in time.

Dwarf stars are technically any star that is in its core phase of life. They are dwarves in comparison to giant stars. The sun is a G-type dwarf star, for instance.

The star is a K-type dwarf, which means it is cooler and smaller than the sun (stars are labelled froom hottest/most massive ~~coolest~~ least hot/least massive: O, B, A, F, G, K, and M for historical reasons).

Planet formation is a complicated and still somewhat young field of study. Planets being close to their stars was a real shock 20 years ago when we stared finding them. The best models we have for this is planetary migration, where the planets form farther aewy from the star, but friction/drag forces from the nebula from which they formed causes them to slow down and fall into smaller orbits.

This planet continues to see its orbit degrade for even more complex reasons, related to both drag -- it is interacting with the star's atmosphere, which is causing it to slow -- and tidal effects. When you're close enough to a massive, rotating body that the differences in gravitational pull strength due to things like variations in density become significant, the rotating body will force you into an orbit that matches its rotation length. If you're already orbiting faster than it is spinning, that means it will slow you down. But slowing down will cause your orbit to shrink, which shortens the time it takes you to complete an orbit, which will make the central body slow you down more, which will shrink your orbit, which...

Win if you can, lose if you must, but always TPK.

The numbers are big, so it can be intimidating, but the math isn't too bad. It's a little bit of multiplication and division. The most daunting bit is a cube-root, which you can find on most scientific calculators these days.

It's hunting down the numbers you need to use that's the trick, and making sure they're all in the right units.

The equation for the Roche limit is the most complex math, but that's just something you look up:

Roche Limit = 2.44 x {the radius of the star} x cube-root(( {the mass of the planet} / {the radius of the planet}^3 ) / ( {the mass of the star} / {the radius of the star}^3 ))

All of the things in the braces are also just values you look up.

The paper doesn't calculate the radius of the star's Roche limit, instead opting to calculate the orbital period of the Roche limit. I've never done a Roche limit calculation for stars, but I have for planets/moons, and I'm not seeing anything that suggests it's different than for planets. So, I think I did this correctly (excepting typos):

The star's Roche limit is about 1.5 million km from its centre (~1 million km above its surface), and the planet's orbit is about 2 million km from the star's centre. Assuming a circular orbit, which should be the case at these distances, the orbit has a circumference of about 12.7 million km, and the planet is whipping around at a speed of about 2.3 million km/h, or 0.2% the speed of light.

Bingo. Especially when what they've done to trigger the comments telllimf them to "play something else" is ask how to extend the thing they already like, or to replace some subsystem that is so clealy not core to the game.

But with 5e, there are also just so many third party releases that you can also replace core systems, like magic, with little difficulty, and people know it.

They don't want to play something else. They're not ready to try something else. They want to keep their dragon ampersand and their dis/advantage rolls, and telling them they're doing something wrong by holding on to that isn't convincing. It just communicates that other games are played by fucking assholes with boundary issues.

Ok, but these discussions aren't happening at you're table. "Well, fuck them then" isn't exactly helpful.

Aye. NodeBB and Lemmy have a couple of rough edges here and there.

Sute, but the thing they like is "D&D", and D&D isn't just a game anymore, it's an identity signifier. Pointing people to other games before establishing yourself as firmly not attacking their identity is going to trigger a fight.

alexanderthedead@lemmy.world said in A lesson so many need to learn: > Anyone who wants to make the claim that the system is bad will have bang their subjective arguments against the steel wall that is its popularity.

Yes, but this is a thing that people want to do. They want to try and dent that popularity, and they want to shift some of it towards their own preferences. It doesn't matter that it's a subjective opinion on what is better or what is bad, it doesn't feel subjective to the person interjecting.

They believe their preferred game is better, they probably have had this discussion numerous times with people who have ignored them or chewed them out for trying to evangelize, and they are infinitely frustrated that others won't see the light.

People who leave popular things behind for niche things often just have this habit of having to bury the thing they left behind. It can't be good. The new thing is better, but the new thing is better both because it is better, and also because the old thing was just objectively bad.

People do this with a lot of things. TV shows, ice cream flavours, toys they used to play with as kids. There's a sense of shame attached to having liked the old thing, not just a sense of joy of having found the new one. It's one of the reasons the people they evangelize to get so defensive: They can sense that they are being judged.

But they definitely can do the thing, because it's a game of make-believe. Again, this is not hammering in a screw, it's mental systems for deciding how imaginary doings transpire.

They didn't ask the wrong question, though. You're seeing a solution they do not want and do not care about then blaming them for not listening to the unsolicited advice.

The problem isn't on their end.