Chemical Sciences: A Manual for CSIR-UGC National Eligibility Test for Lectureship and JRF/Broad Iron K line

In astronomy, the broad iron K line is a spectral line that is an accurate measure of a black hole's immense gravitational force. The name refers to the shape, on a spectrogram, of light emitted by iron atoms near the black hole surface. The light loses energy as it climbs out of the black hole's gravitational well, causing the spectral line to be stretched toward lower frequencies.

A series of observations by the Japanese Suzaku satellite conducted in 2005 and 2006 demonstrates that the broad iron K line is found coming from almost all galaxies and that the signal is real, from strong gravity, and not noise due to poor resolution. Recent data suggests a connection between quasi-periodic oscillations and the broad Iron K line.

Scientists believe that they will be able to use the broad iron K line to image black holes.