Egg shaped gas giant
- Thread starter Sooden
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It is not gravity, I see that often on gas giants much further from the star. These planets spin fast which causes this shape.
Even the Earth is a bit depressed at the poles.
Even the Earth is a bit depressed at the poles.
You're right - looking at it, the angle is wrong for a tidal pull.
Is the earth really a bit depressed at the poles when viewed from space?
Hopefully they will introduce that for fastspin stars too.
Here's a picture of Achenar, how he is supposed to be!
https://upload.wikimedia.org/wikipedia/commons/thumb/5/5d/Achernar.svg/2000px-Achernar.svg.png
Here's a picture of Achenar, how he is supposed to be!
https://upload.wikimedia.org/wikipedia/commons/thumb/5/5d/Achernar.svg/2000px-Achernar.svg.png
The earth isn't just depressed at the poles, it's elongated at the equator. Most of the effect is on the oceans rather than the land masses. This pancake effect is caused by spin.
However the Earth also looks like an "egg" and that is caused by tidal forces by the moon on the ocean.
If it's that close to the sun, then it is tidally locked and the bulge is also due to tidal forces. The angle is because the planet rotation axis is tilted, so yeah it's probably a system map bug. Though you should look at from your cockpit to see if the bug translates to actual planet.
Also tidal bulges don't point directly at the object. Mass has inertia and gravity isn't instantaneous (travels at the sites of light). Hence the bulge from tidal forces should trail behind the point at where the object used to be the sky as seen from the planet's "surface".
However the Earth also looks like an "egg" and that is caused by tidal forces by the moon on the ocean.
If it's that close to the sun, then it is tidally locked and the bulge is also due to tidal forces. The angle is because the planet rotation axis is tilted, so yeah it's probably a system map bug. Though you should look at from your cockpit to see if the bug translates to actual planet.
Also tidal bulges don't point directly at the object. Mass has inertia and gravity isn't instantaneous (travels at the sites of light). Hence the bulge from tidal forces should trail behind the point at where the object used to be the sky as seen from the planet's "surface".
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Looks like a bit of both. It's tidally locked, so the tidal forces are always working upon the same part of the planet - not that that's all that important for a gas giant - and it's spinning 5 times as fast as Earth.
Wow, unless I've dropped a digit, that means its surface at the equator is moving at over 245,000 km/h.
EDIT: Nevermind, brainfart on the maths, it's more like 108,000.
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How can a spinning gas giant be tidally-locked? Is the stellar forge drunk again?
Orbital period 0.2 days
Rotation period 0.2 days
This is the definition of tidally locked.
However, if you're asking how a planet with a rarified gaseous upper atmosphere could be treated like a liquid or a solid for the purposes of tidal locking by tidal friction, that's a better question.
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Tidally locked means it's rotating at the same speed as its orbit, so one side always faces the object it's orbiting. So yeah, it's also circling that star five times per day.
He also included "spinning gas giant" so the question may not have been so obvious. See above post.
Heh - that is a good point. Coincidence?
I try hard to make good points so I hope it's not a coincidence. Lol. But yeah, the "friction" in this case is probably caused by atmospheric ions moving through the magnetic fields of the planet and the very nearby star. Which would cause a gradual reduction in angular momentum for the gas giant.
At this point may I remind you of Hal Clement's 1954 novel "Mission of Gravity". Just because this thread reminded me of it.
Still one of my favourite sci-fi books.
IIRC the planet Mesklin had ~3G on equator & ~700G on poles...
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