> is there some sort of gravitational body in the middle that makes everything orbit in galaxies?
No. The Sun's orbit is determined by the total mass of stars, gas, and dark matter interior to the orbit. This is mostly due to the stars (we're not far enough out from the center for dark matter to be the dominant component) and is on the order of several tens of billions of solar masses.
(There is a supermassive black hole at the center of our galaxy, but its mass is only about 4 million solar masses, so it's negligibly small compared to the mass of all the stars.)
The same way that the Earth can orbit the centre of mass of the solar system and also be within the solar system. We say that the Earth orbits the Sun because that's where 99.86% of the mass of the solar system is located.
The Sun in turn orbits the the centre of mass of the Milky Way. But I don't think that the mass of the Milky way's central supermassive black hole dominates in the same way.
But the earth doesn't orbit around the solar system. it orbits around the sun as part of the solar system. the solar system as a unit orbits around the center of the galaxy. if you've ever seen the concept images of the Oort cloud, you could visualize that snowball looking roundish object as a visual for the solar system traveling through the galaxy.
Around the center of the Milky Way. The sun orbits the center just like the planets orbit the sun.
is there some sort of gravitational body in the middle that makes everything orbit in galaxies? it must be massive right
One of today's lucky ten thousand. Most galaxies have a black hole at the center that mass at least a hundred thousand times more than our sun: https://en.wikipedia.org/wiki/Supermassive_black_hole
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> is there some sort of gravitational body in the middle that makes everything orbit in galaxies?
No. The Sun's orbit is determined by the total mass of stars, gas, and dark matter interior to the orbit. This is mostly due to the stars (we're not far enough out from the center for dark matter to be the dominant component) and is on the order of several tens of billions of solar masses.
(There is a supermassive black hole at the center of our galaxy, but its mass is only about 4 million solar masses, so it's negligibly small compared to the mass of all the stars.)
The same way that the Earth can orbit the centre of mass of the solar system and also be within the solar system. We say that the Earth orbits the Sun because that's where 99.86% of the mass of the solar system is located.
The Sun in turn orbits the the centre of mass of the Milky Way. But I don't think that the mass of the Milky way's central supermassive black hole dominates in the same way.
Orbit around the center. It’s like saying the Earth orbits around the solar system.
But the earth doesn't orbit around the solar system. it orbits around the sun as part of the solar system. the solar system as a unit orbits around the center of the galaxy. if you've ever seen the concept images of the Oort cloud, you could visualize that snowball looking roundish object as a visual for the solar system traveling through the galaxy.