The question that I started off with was, I thought, very simple. It was just ‘Is there a massive black hole at the center of the Milky Way?’ But one of the things I love about science is that you always end up with new questions. Andrea M. Ghez Read Quote
We have this interesting problem with black holes. What is a black hole? It is a region of space where you have mass that’s confined to zero volume, which means that the density is infinitely large, which means we have no way of describing, really, what a black hole is! Andrea M. Ghez Read Quote
Proof of the black hole is a tremendous amount of mass inside a very small volume. There’s 4 million times the mass of our sun within a region that’s comparable to the size of our solar system. Andrea M. Ghez Read Quote
One of the big mysteries about the black hole at the center of the galaxy is, ‘Why don’t we see emission from matter falling onto the black hole, or, rather, the black hole eating up its surroundings?’ Andrea M. Ghez Read Quote
There’s a large cluster of stars that are orbiting the center of our galaxy. And by measuring the motion of stars, and in particular, their orbits, we can figure out whether or not there’s a central black hole. Andrea M. Ghez Read Quote
The key to proving that there’s a black hole is showing that there’s a tremendous amount of mass in a very small volume. And you can do that with the motions of stars. The way the star moves around the center of the galaxy is very much like the way the planets orbit the sun. Andrea M. Ghez Read Quote
Fortunately, most things around the supermassive black hole are just going to go around it. They’re going to orbit it. They don’t actually get sucked in. Andrea M. Ghez Read Quote
The Keck telescope, which is the largest in the world, had opened just before I began my faculty position at UCLA. Andrea M. Ghez Read Quote
The key to proving that there’s a black hole is showing that there’s a tremendous amount of mass in a very small volume. And you can do that with the motions of stars. Andrea M. Ghez Read Quote
As an astronomer, I get to ignore the details of the things that we don’t understand. There’s a lot of work that we can do on scales that we do understand, and there is actually a finite size that I can associate with a super massive black hole. Andrea M. Ghez Read Quote
