OREANDA-NEWS NASA's Chandra Observatory has discovered a black hole that rotates slower than most of its brethren - this is stated on the official website of the observatory, writes Gazeta.ru.

The black hole is located inside the quasar H1821 + 643, located at a distance of 3.4 billion light years. The object contains from three to 30 billion solar masses, making it one of the most massive black holes known.

Using data from Chandra, NASA astronomers found that the black hole rotates at about half the speed of light - twice as slow as most black holes. According to scientists, this rotation rate supports the idea that the most massive black holes grow by merging with other holes.

Supermassive black holes growing in this way undergo large rotation changes, including slowing down or rotating in the opposite direction.

Scientists were able to calculate the speed of the black hole's rotation thanks to X-ray images from the observatory, radio data and optical images from the PanSTARRS telescope in Hawaii. All of the data were collected over the course of a week.