Astronomers measure the mass of a dormant black hole, our solar system's lost protoplanet, and more science stories

Astronomers have successfully measured the mass of a dormant black hole located in the Milky Way galaxy. This black hole, designated Gaia BH1, is the closest known to Earth, situated approximately 1,560 light-years away. Its mass is estimated to be about 10 times that of our Sun, and it orbits a Sun-like star, which is unusual for dormant black holes. The discovery was made possible by observing the gravitational influence of the black hole on its companion star.

This measurement provides crucial data for understanding the formation and evolution of dormant black holes, which are notoriously difficult to detect and study.