Just about every scientist who studies black holes is convinced they exist. But so far, the case is entirely circumstantial — no one has ever actually seen one.
A team of astronomers hopes to change that in the next few years. The team is linking radio telescopes around the world to produce sharp images of the possible black holes at the centers of galaxies.
The project is known as the Event Horizon Telescope. The event horizon is a black hole’s “surface” — the point of no return for anything that falls into the black hole. Matter and energy pass through the horizon, but only in one direction — nothing can come back out, including light.
Albert Einstein’s theory of gravity says that a black hole should bend the light from objects behind it to produce a bright ring — an effect that would make it possible to “see” the black hole.
The project will target the supermassive black holes at the center of the Milky Way and another galaxy, M87. Although these are huge objects, they’re so far away that they are tiny in our sky — the size of an orange at the distance of the Moon.
Combining telescopes at locations around the world provides sharper views — it’s like seeing with a part of a giant telescope. So far, the project has used a few telescopes. Project leaders are trying to upgrade some of those telescopes, while adding others to the network — steps that could provide undeniable proof that black holes really do exist.
Script by Damond Benningfield, Copyright 2012
For more skywatching tips, astronomy news, and much more, read StarDate magazine.