Chances are if you’re interested in astronomy you’ve heard the terms quasars and black holes. They’re not exactly the same things, but it turns out that in many places in space, quasars and black holes are locked together in a cosmic dance. Quasars are bright objects that can outshine a trillion suns. Scientists think that quasasrs are the extremely luminous cores of galaxies. However, buried deep within those cores are dark secrets: black holes. These powerful and hidden objects have gravitational pulls so intense that nothing — not even light — can escape them. It may seem ironic but black holes are very likely the power sources for quasars.
How can this be?
The picture above is an artist’s concept by Aurore Simonnet of Sonoma State University of a black hole powering a quasar called QSO I Zw 1. In this image, the black hole is buried in the center of a disk of gas and dust (brown and yellow cloudy area in center). Scientists have discovered a cold ring of gas around a supermassive black hole at the center of the galaxy that makes up the quasar. To make QSO I Zw 1 shine with the brilliance of a trillion suns, it has to have a black hole with the mass of millions to billions of suns feeding on gas at the core of the galaxy.
Here’s how it works: the black hole pulls in material (gas, dust, stars) from the surrounding region of space. The material whirls around the black hole before swirling in like water down a drain. All this activity generates intense friction, which heats the gas and causes it to shine brightly. Although nothing can escape the crushing gravity of a black hole once past its boundary (called the event horizon), matter sometimes escapes after approaching — but not crossing — the event horizon. The material flies out in high-speed jets of gas that are often ejected near the poles of the black hole. Astronomers are still working to understand exactly how this works. The jets are represented in this image by yellow lines emanating from the center of the gas disk where the black hole is lurking.
Astronomers continue to study this very interesting galaxy as it interacts with a close galactic neighbor. The result of a close brush between galaxies is often a burst of star birth activity — and scientists want to know if it might also spur quasar activity as well.