Black Hole Visualization

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NASA creates stunning new black hole visualization
Deborah Byrd in SPACE | September 27, 2019

For decades, astronomical theorists have told us that a black hole’s powerful gravity would warp the space around it. This new visualization from NASA’s Goddard Space Flight Center is the best yet at showing exactly how.

For decades, astronomical theorists have told us that a black hole’s powerful gravity would warp the space around it. This new visualization from NASA’s Goddard Space Flight Center is the best yet at showing exactly how.

The black hole is seen nearly edgewise in this new visualization from NASA. The turbulent disk of gas around the hole takes on a double-humped appearance. The black hole’s extreme gravity alters the paths of light coming from different parts of the disk, producing the warped image. “What we see depends on our viewing angle,” NASA said. Image via NASA’s Goddard Space Flight Center/Jeremy Schnittman.

NASA released this new new visualization of a black hole this week, generated by astrophysicist Jeremy Schnittman, using custom software at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Schnittman’s areas of expertise include computational modeling of black hole accretion flows. That’s what you’re seeing in this visualization, the flow of material around a black hole as it might appear if you could see the hole up close (but not too close!), and from the side. Yes, black holes are black; no light can escape them. All the action is in the area immediately surrounding the hole, because the hole’s powerful gravity warps its surroundings, distorting our view, NASA said, “as if seen in a carnival mirror.” NASA explained on September 25, 2019:

The visualization simulates the appearance of a black hole where infalling matter has collected into a thin, hot structure called an accretion disk. The black hole’s extreme gravity skews light emitted by different regions of the disk, producing the misshapen appearance.

Bright knots constantly form and dissipate in the disk as magnetic fields wind and twist through the churning gas. Nearest the black hole, the gas orbits at close to the speed of light, while the outer portions spin a bit more slowly. This difference stretches and shears the bright knots, producing light and dark lanes in the disk.

Viewed from the side, the disk looks brighter on the left than it does on the right. Glowing gas on the left side of the disk moves toward us so fast that the effects of Einstein’s relativity give it a boost in brightness; the opposite happens on the right side, where gas moving away us becomes slightly dimmer. This asymmetry disappears when we see the disk exactly face on because, from that perspective, none of the material is moving along our line of sight.

Closest to the black hole, the gravitational light-bending becomes so excessive that we can see the underside of the disk as a bright ring of light seemingly outlining the black hole. This so-called “photon ring” is composed of multiple rings, which grow progressively fainter and thinner, from light that has circled the black hole two, three, or even more times before escaping to reach our eyes. Because the black hole modeled in this visualization is spherical, the photon ring looks nearly circular and identical from any viewing angle. Inside the photon ring is the black hole’s shadow, an area roughly twice the size of the event horizon — its point of no return.