Compact Objects

Read 23.4 Pulsars and the Discovery of Neutron Stars to understand how the discovery of mysterious “pulsars” provided the first observational evidence that neutron stars really exist.
Watch the BBC clip What are Pulsars? to hear from Jocelyn Bell as she recounts her discovery of pulsars.
When the most massive stars collapse, not even neutrons can hold up against the weight of gravitational collapse. The result is an object with so much gravity that not even light can escape. Explore 24.5 Black Holes to learn about the formation and characteristics of black holes, including the concept of event horizons and singularities.
Watch this video to see what would happen If Our Sun Became a Black Hole
In 2019, a team of astronomers from around the world released the first picture ever showing a black hole. Strictly speaking, the image doesn’t show the black hole itself, but rather the light from the hot accretion disk around the black hole. Watch the news summary First Image of a Black Hole to learn about the discovery. This seems to be further irrefutable evidence that black holes are real.
Check out this amazing Simulation of a Black Hole, which includes an accurate representation of how the gravity around a black hole can distort light and time. If you can’t get the simulation to work on your computer, you can watch this brief video of the Black Hole Simulation instead.