Optical image of the elliptical galaxy M87 (NGC 4486) showing the profile of its brightness. The white line plots the brightness measured along the yellow line which passes through the centre of the galaxy. The brightness has a huge cusp at the centre proving that in this region the density of stars is extremely high. Current models suggest that a black hole of 2.6 billion solar masses lies in the core of M87 pulling all the stars towards the centre. The black hole also powers a 5000 light years long jet of plasma (not visible here) which corresponds to the small bump on the inner right part of the brightness profile.