... X-rays are made up of photons that are emitted from stars, or quasars, or supernovae, the sun, or simply: anything that is undergoing a change either in size or temperature or giving out heat. ... in an X-ray binary star system, in which one normal star's orbit is crossed by a neutron star, when the neutron star by means of gravitational pull takes matter from the normal star X-rays form. ... Artists conception of a normal star (HDE 226868) and a black hole taking matter from the normal star. ...