Our galaxy's pretty ordinary, garden-variety. So if we believe our galaxy has a super massive black hole, that tells us that most, if not all, galaxies host such a black hole at their centers. Andrea M. Ghez blackcentergalaxy Change image and share on social
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 blackcentercentral share on social
An ordinary black hole is thought to be the end state of a really massive star's life. Andrea M. Ghez blackendhole Change image and share on social
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 blackcenterend share on social
Black holes are very exotic objects. Technically, a black hole puts a huge amount of mass inside of zero volume. So our understanding of the center of black holes doesn't make sense, which is a big clue to physicists that we don't have our physics quite right. Andrea M. Ghez amountbigblack share on social
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 associateastronomerblack share on social
The star S0-2 orbits around Sgr A* every 16 years and will go through its closest approach in 2018. That's an opportunity to test Einstein's General Relativity theory through very precise measurements of this star's short period orbit. Andrea M. Ghez approachcloseeinstein share on social
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 amountblackcomparable Change image and share on social
The atmosphere is great for people - it allows us to survive - but it's a real headache for astronomers. Andrea M. Ghez astronomeratmospheregreat Change image and share on social
Astronomers are obsessed with building larger and larger telescopes. There are two promises that we make with bigger telescopes: that they can see fainter things and that they see more detail. But it's been really hard to follow through on that second promise because of atmospheric distortion. Andrea M. Ghez astronomeratmosphericbig share on social