Shredded stars reveal how black holes ignite trillion-sun flares

Supermassive black holes are among the most enigmatic objects in the universe. They typically weigh millions or even billions of times the mass of the sun and sit at the centers of most large galaxies. At the heart of the Milky Way lies Sagittarius A*, our galaxy's supermassive black hole, with a mass of about four million suns. But these black holes do not emit light, so astronomers can only detect them indirectly through their effects on nearby stars and gas.