They spotted a bunch of stars orbiting around in the center at crazy speeds around what appears to be nothing but the only thing that could have that much mass to swing those stars around like moons would have to be insanely dense which could only be justified by being a super massive black hole
That's because they actually observed it.
Yes. There is a supermassive black hole at the center of the galaxy and a number of stellar mass black holes through the rest of it.
Perhaps you mean "thought to be"? - It is believed that all, or most, galaxies have a supermassive black hole at their center.
The galactic centre is the central region of a galaxy. Most, if not all galaxies have a supermassive black hole at their centre.
A quasar is believed to have a supermassive black hole at its center. The radiation is emitted outside the black hole's event horizon - from matter that is falling into the black hole.
That's because they actually observed it.
A blazar is an elliptical galaxy with a supermassive black hole at the center.
A Supermassive black hole .
The supermassive blackholes at the center of galaxies.
It seems that just about EVERY galaxy has a huge ("supermassive") black hole in its center.
Not much actually. Scientists are still looking into it. What they do know though is that it has eaten up everything around it. Because of that, the supermassive black hole exists in a pitch black, empty area in the center of the Milky Way.
Most astrophysicists believe that there is a supermassive black hole at the center of the Milky Way.
Most galaxies - the larger ones at least - have a supermassive black holes in their center.
Quasars have a large black hole, called a "supermassive black hole". The term "supermassive black hole" simply means that it has millions or even billions of solar masses.
All galaxies have supermassive black holes in their centers.
Probably yes, although we cannot be certain. The gas and dust clouds prevent us from seeing the center. Scientists believe that there may be a supermassive black hole at the center of the Milky Way, as there appear to be supermassive black holes at the centers of many large galaxies.
I believe that would be exactly the term - "active supermassive black hole". The term "active galaxy" or "active radiogalaxy" is also used for a galaxy that produces large amount of certain radiations; however, such radiation is really caused by the supermassive black hole.