Summary:

- This article discusses a new study that has found evidence of a "supermassive" black hole at the center of our Milky Way galaxy. This black hole, named Sagittarius A*, is estimated to be about 4 million times the mass of our Sun.

- Researchers used observations from the Gravity instrument on the European Southern Observatory's Very Large Telescope to track the motion of stars near the center of the galaxy, which allowed them to measure the mass and location of the black hole with unprecedented accuracy.

- The findings provide strong evidence that Sagittarius A* is indeed a supermassive black hole, which is a key prediction of the standard model of galaxy formation and evolution. Understanding the properties of this black hole can give us important insights into the history and structure of our galaxy.