- #1
Buzz Bloom
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- TL;DR Summary
- NGTS-10b, illustrated generically, is the closest and fastest-orbiting giant planet yet discovered, circling its home star in only 18 hours. NGTS-10b is a little larger than Jupiter, but it orbits less than two times the diameter of its parent star away from the star’s surface. When a planet orbits this close, it is expected to spiral inward, pulled down by tidal forces to be eventually ripped apart by the star’s gravity.
https://apod.nasa.gov/apod/ap200226.html
I am hoping a PF participant can help me understand why the tidal forces cause the NGTS-10b planet to fall towards it's star. I more-or-less understand why our moon's tidal forces on the Earth cause the Earth's rotation period to decrease, and the conservation of angular momentum of the Earth-moon system causes the moon to move away from the Earth. The only ideas I can think of are probably wrong.
(1) If the orbital spin direction of NGTS-10b about it's star is in the opposite direction of the rotational spin direction of it's star, that might explain this effect.
(2) If the orbital spin direction of NGTS-10b about it's star is in the opposite direction of the rotational spin direction of NGTS-10b, that might explain this effect.
The quoted text says the phenomenon depends of the distance of the planet from it's star. I do not understand this at all.
(1) If the orbital spin direction of NGTS-10b about it's star is in the opposite direction of the rotational spin direction of it's star, that might explain this effect.
(2) If the orbital spin direction of NGTS-10b about it's star is in the opposite direction of the rotational spin direction of NGTS-10b, that might explain this effect.
The quoted text says the phenomenon depends of the distance of the planet from it's star. I do not understand this at all.