Can a star orbit a planet
In: Planetary Science
No. A star has more mass and therefore gravity than a planet, so the planet will be the one orbiting the star not the other way around
No, because a star is much more massive than a planet. In a two-body system, the smaller body technically doesn’t orbit the star, but both bodies orbit their common center of mass. That is, two equal masses will orbit an empty point in space rather than one orbiting the other. It’s just that when the mass difference becomes large enough, that “common center of mass” is located *inside* one of the two objects, which is precisely what happens in the solar system. Because stars are always more massive than planets (almost by definition), a star-planet system can’t have the center of mass inside the planet.
Shooting from the hip here, but if a planet had that much mass it would have turned into a star. So no, stars and planets by definition of the words will always be larger/smaller and have smaller objects orbit them.
In theory yes, but in actuality, no. Stars are far more massive than planets, enough that they fully resist the gravitational pull of a planet. A star could theoretically orbit a planet if it were smaller than the planet, but this has never been the case and likely never will be.
Two bodies in orbit technically both orbit each other. The center of their path is the combined center of gravity of both bodies. If the star is much more massive than the planet, it will look like the planet is going around the star and the star is barely moving at all.
If I remember correctly, the center of mass of our solar system is right near the surface of the sun, and you can see the sun kind of wiggling around that point in its orbit
I don’t think so. The star has to orbit around something heavier than itself, and a planet can’t be heavier than a star.
A planet can be at most around 10x the mass of Jupiter, so around 1.89813×10^28 kilograms
https://hub.jhu.edu/2018/01/23/size-limit-planets-brown-dwarfs/
The minimum mass for a star that does star stuff is about 80 times Jupiter
[https://www.atnf.csiro.au/outreach/education/senior/astrophysics/stellarevolution_mainsequence.html#:~:text=Stellar%20Mass,-As%20was%20apparent&text=The%20lower%20mass%20limit%20for,forms%20a%20brown%20dwarf%20instead](https://www.atnf.csiro.au/outreach/education/senior/astrophysics/stellarevolution_mainsequence.html#:~:text=Stellar%20Mass,-As%20was%20apparent&text=The%20lower%20mass%20limit%20for,forms%20a%20brown%20dwarf%20instead).
NASA found some stuff that they’re pretty sure are brown dwarves and estimate the smallest one at only 3 or four times as massive as Jupiter, which means that a brown dwarf this small could orbit a huge planet
[https://www.psu.edu/news/eberly-college-science/story/nasas-webb-telescope-identifies-tiniest-free-floating-brown-dwarf/#:~:text=The%20smallest%20of%20these%20weighs,collapse%20and%20form%20a%20star](https://www.psu.edu/news/eberly-college-science/story/nasas-webb-telescope-identifies-tiniest-free-floating-brown-dwarf/#:~:text=The%20smallest%20of%20these%20weighs,collapse%20and%20form%20a%20star).
Usually they’re about 75 times as massive as Jupiter though https://www.britannica.com/science/brown-dwarf#:~:text=Brown%20dwarfs%20usually%20have%20a,of%20about%2013%20Jupiter%20masses.
Short answer: Not unless something very strange is going on.
Long answer: the problem is that the planet would have to be significantly more massive than the star. What makes this a problem is that stars work by their own mass pulling the star together via gravity, so anything bigger than a star *becomes* a star (until you hit the limit for black holes, anyway). For a planet to be big enough thar a star could orbit it, you’d have to have some mechanism in place to prevent the planet from turning into a star itself. I’m not sure we know of anything that can do that.
No. Strictly speaking, in an orbit, two object orbit their common center of mass, called a barycenter. This center is closer to the center whichever object has more mass. For very large mass differences (such as between Earth and the sun) it’s close enough that we usually just say the less massive thing orbits the more massive thing.
Stars have much more mass than planets. Looking at the limits of what are generally considered stars and generally considered planets: the least massive stars are still about 6 times more massive than the most massive planets (~80 Jupiter masses vs ~13). So in all cases, the center of mass will still be closer to the star.
NO, by definition.
– A planet orbits a star by definition.
– A moon orbits a planet by definition.
What you’re asking is similar to asking if an airport can fly and land on an airplane.
The more massive object in a two-body system will orbit closest to the centre of that system.
The upper limit for a planet is [13](https://phys.org/news/2019-11-large-planet.amp) times the size of Jupiter. The lower limit for a star is around [75](https://en.wikipedia.org/wiki/Minimum_mass) times the size of Jupiter.
Given this, you can see that a star will always be too big to orbit a planet.
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