Animated Sequence of Stars Orbiting Sagittarius A*

Animated sequence of ESO’s Very Large Telescope Interferometer (VLTI) images of stars around the Milky Way’s central black hole. This animation shows the orbits of the stars S29 and S55 as they move close to Sagittarius A* (center), the supermassive black hole at the heart of the Milky Way. As we follow the stars along in their orbits, we see real images of the region obtained with the GRAVITY instrument on the VLTI in March, May, June and July 2021. In addition to S29 and S55, the images also show two fainter stars, S62 and S300. S300 was detected for the first time in new VLTI observations reported by ESO.

Using Gemini North of the international Gemini Observatory, a program of NSF’s NOIRLab and ESO’s VLT, astronomers have measured more precisely than ever before the position and velocity of these stars S29 and S55 (as well as stars S2 and S38), and found them to be moving in a way that shows that the mass in the center of the Milky Way is almost entirely due to the Sagittarius A* black hole, leaving very little room for anything else.