X-ray image of SS 433, a black hole candidate, taken by the Einstein Observatory satellite. SS 433 is the central white spot. It is believed to consist of a normal star whose outer gases are falling onto a compact companion star (a neutron star or a black hole) in a spiralling accretion disc. This whirling disc's hot gases generate intense X-ray emission. The disc also emits clouds of hot gas, which shoot out on either side like jets of spray from a garden sprinkler. The jets are the bright areas on either side. The colours are coded for X-ray intensity, from white for the most intense to blue for the least intense.