NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) and the European Space Agency's XMM-Newton, have together accurately measured, for the first time, the spin rate of a black hole with a mass two million times that of our sun.
NASA astronomers describe NGC 3344 as a "glorious" spiral galaxy around half the size of the Milky Way, which lies some 25 million light-years distant.
Many giant black holes in the centre of galaxies are spinning faster than at any time in the history of the universe, and may have been set in motion comparatively recently, new research shows.
