A black hole is a point in space where the pull of gravity is so intense that not even light can escape it. Black holes form when a star goes supernova, shooting vast amounts of matter into space while folding in or collapsing upon itself. (Don’t fret: Our sun would need about 20 times its actual mass in order to turn into a black hole.)
Other stars generate stellar winds, described by Hubble Space Telescope personnel as: “fast-flowing streams of particles that are emitted from a star.” The extreme gravitational pull of a black hole allows it to slurp up some of this material.
Although the visualization offers a sense of the variety of black holes, these objects are depicted here as being far larger in comparison to their companion stars and accretion disk than they actually are.
Because black holes cannot emit light, scientists are unable to observe these objects directly using telescopes. However, matter falling into a black hole gradually heats up and glows, eventually in X-rays. It is on those X-rays that this visualization is based.
The image depicts 22 X-ray binaries in both our Milky Way galaxy and the nearby Large Magellanic Cloud. According to a NASA statement accompanying the film, the black hole is depicted as a black dot in the middle of an orange-red accretion disc, while the star is depicted as a bluish- or yellowish-white sphere scaled to match its size.
The black hole of an X-ray binary can collect energy from its star in two ways. The first is that a stream of gas may flow directly from the star of the host galaxy into the black hole, swirling “like water goes down a drain” according to Scientific American.
For example, take the first ever confirmed black hole, Cygnus X-1. Its surface, called the event horizon, only stretches about 77 miles (124 kilometers) across. However, the visualization shows Cygnus X-1 as being far larger, more in line with the black hole’s mass than its volume.
The visualization’s viewing angles demonstrate how we can see the systems from Earth, while the orbital motion shown is 22,000 times faster than observed.