UA scientists organizing first-ever black hole photograph
Event Horizon Telescope will combine images from 50 telescopes
A black hole is a collapsed star whose gravitational pull is so strong that not even light can escape, and a spot where our understanding of the laws of physics gets fuzzy.
In what was once possible only in "complete science fiction," scientists at the University of Arizona are organizing the creation of a virtual super-telescope that will take the first photographs of a black hole, and test Einstein’s General Theory of Relativity.
Astronomers, physicists and related scientists from around the world will meet in Tucson on Wednesday to discuss the creation of an Event Horizon Telescope that would combine the power of up to 50 individual telescopes from around the world.
“In essence, we are making a virtual telescope with a mirror that is as big as the Earth,” Shep Doeleman said in a press release.
Doeleman is the assistant director of the Haystack Observatory at Massachusetts Institute of Technology (MIT), where that data will be processed after it’s collected.
The telescopes are spread across the earth from the Submillimeter Telescope on Mt. Graham in Arizona to a 10-meter dish on the South Pole.
Changing the game
It was only ten years ago when researchers began to understand the basic properties of black holes, said Dimitrios Psaltis, an associate professor of astrophysics at the University of Arizona’s Steward Observatory who helped organized the conference.
Black holes are areas in space where the gravitational pull is so strong, not even light can escape. Scientists can identify at least 25 black holes in our galaxy, but there could be tens of thousands, Psaltis said.
They are created when a star collapses and since black holes emit no light, they are nearly indistinguishable on the dark backdrop of the galaxy.
The event horizon of the black hole is the point at which black holes enormous gravitational pull takes hold and sucks in all light. Beyond this point no scientific law can describe what happens.
"Anything that gets this close to a black hole will never be seen again," said Dan Marrone, an assistant professor of astronomy at the UA who also helped gather the scientists to discuss the project.
The event horizon will allow scientists to capture the shadow of the black hole, ringed in illuminated cosmic matter.
“As dust and gas swirls around the black hole before it is drawn inside, a kind of cosmic traffic jam ensues,” Doeleman explained in the release.
“Swirling around the black hole like water circling the drain in a bathtub, the matter compresses and the resulting friction turns it into plasma heated to a billion degrees or more, causing it to ‘glow’ – and radiate energy that we can detect here on Earth.”
Until now the idea of being able to photograph a black hole was “complete science fiction,” Psaltis said.
In 2008, scientists at MIT, including Doeleman, successfully combined the data from three telescopes to measure the size of the black hole in the center of the universe. But with only three telescopes they could not create a clear image of the black hole’s shape.
“The size is exactly what we would expect from a black hole four million times the size of the sun,” Psaltis said.
Researchers are focusing on the black hole in the center of the Milky Way galaxy because in relation to larger black holes, it is the closest and will produce the highest resolution pictures.
The Atacama Large Millimeter Array (ALMA) in Chile is a crucial piece to the project.
The telescope is the only one in the region suitable for the project and is the product of 50 radio antennas itself. The large number of antennae equals a comparable telescope of 90 meters.
“It completes the puzzle in many different ways,” Psaltis said of the ALMA.
The pictures produced by the Event Horizon Telescope will gain clarity as additional telescopes are added over the years, Psaltis said.
"I don’t think there will be any major problems that will happen. We know how to make these telescopes work, we know how to combine them and we know the side of was we are looking at," Psaltis said.
“It’s a major effort but we are all very excited to make it happen.”
Testing Einstein’s theory
Einsteins Theory of Relativity was the first indicator black holes even existed, but lacking clear pictures, physicists have had to rely on circumstantial evidence. A clear outline will make or break an important part of the theory.
According to Einstein’s theory, a black hole can only be a perfect circle.
“No matter what you do to a black hole, you make it start rotate faster, tilt it, its always appears the same,” Psaltis said.
“If it turns out that there is something wrong with it [Einstein’s theory] then we are going to have a lot of headaches to deal with,” Psaltis said. “ But this is what science is all about.”