8,000 kilometers per second: Star with the shortest orbital period around black hole discovered

Researchers at the University of Cologne and Masaryk University in Brno (Czech Republic) have discovered the fastest known star, which travels around a black hole in record time. The star, S4716, orbits Sagittarius A*, the black hole in the center of our Milky Way, in four years and reaches a speed of around 8,000 kilometers per second. S4716 comes as close as 100 AU (astronomical unit) to the black hole--a small distance by astronomical standards. One AU corresponds to 149,597,870 kilometers. T...