This week is black hole week, and NASA is celebrating by sharing some stunning visualizations of black holes, including a frankly disturbing visualization to help you picture just how large a supermassive black hole is. Supermassive black holes are found at the center of galaxies (including our own) and generally speaking, the bigger the galaxy, the bigger the black hole.
While a typical black hole weighs up to around 10 times the mass of the sun, supermassive black holes can weigt millions or even billions of times the mass of the sun. These objects are incredibly dense, though, and it’s hard to picture just how big such an object would be. That’s the point of this video comparison, which shows the size of different types of black holes in comparison to our solar system, scaled according to their shadows.
Learning about black holes is challenging because their tremendous gravity means that they absorb light that comes too close to them — however, they often have disks of dust and gas swirling around them that rubs together and gets hot, making them visible to telescopes. Astronomers can’t directly see the black holes themselves, but they can see this warm matter, which is how the Event Horizon Telescope project has been able to capture famous images of black holes.
Supermassive black holes are particularly interesting to study because we are still learning about their relationship to the galaxies which they inhabit, and about how they grow so large.
“Direct measurements, many made with the help of the Hubble Space Telescope, confirm the presence of more than 100 supermassive black holes,” said Jeremy Schnittman, a theorist at NASA’s Goddard Space Flight Center, in a statement. “How do they get so big? When galaxies collide, their central black holes eventually may merge together too.”
This merging process would be epic, producing such great force that gravitational waves would be detectable from Earth. But to tune into these waves, we’ll need a new instrument like the upcoming Laser Interferometer Space Antenna mission, a collaboration between NASA and the European Space Agency that will use three spacecraft that shoot lasers toward each other and which will be able to detect these gravitational waves.
“Since 2015, gravitational wave observatories on Earth have detected the mergers of black holes with a few dozen solar masses thanks to the tiny ripples in space-time these events produce,” said Goddard astrophysicist Ira Thorpe. “Mergers of supermassive black holes will produce waves of much lower frequencies which can be detected using a space-based observatory millions of times larger than its Earth-based counterparts.”
