First image of black hole revealed, MU astronomy professor gives insight
The Event Horizon Telescope collaboration announced the first image taken of the black hole at the center of M86, an elliptical galaxy that lies 55 million light-years from Earth.
Apr. 14, 2019
A team of researchers from the Event Horizon Telescope project revealed the first image of a black hole April 10. The image was assembled from data gathered by eight radio telescopes around the world including Hawaii, Chile and Spain.
The results were announced concurrently at news conferences in Washington, D.C, and five other places around the world, according to The New York Times.
“We have been hunting this for a long time,” Jessica Dempsey, co-discoverer and deputy director of the East Asian Observatory in Hawaii, said during an interview with AP. “We have been getting closer and closer with better technology.”
Three years ago, scientists using an extraordinarily sensitive observing system heard the sound of two much smaller black holes merging to create a gravitational wave, as Einstein predicted. The new image, published in the Astrophysical Journal Letters, was announced around the world, according to AP.
Angela Speck, MU astrophysicist and director of astronomy, said the reveal of the picture marked a new step forward for the astrophysics community. It also confirmed ideas and hypotheses that were brought up in the past decades.
Speck said what makes the first image of a black hole substantial is the complex technology involved behind it.
Because of the high density of black holes, they cannot be seen through visible light but rather through radio waves.
“It is actually the giant radio dishes that are doing the observations,” Speck said. “Think about the big radio dishes you have by cable stations that provide you the satellite data. [The radio dishes used in black hole experiments] are much bigger than the ones we see in daily life. And the bigger the dishes are, they are more likely to collect things you can see.”
Essentially, researchers were trying during the project to mimic a radio dish big enough to detect all the radio waves. The intimated radio dish was equivalent to the size of the earth.
Speck said a lot of times our eyes don’t see things surrounding us not because they are not bright enough, but rather they are too close together. In this case because of the tightness of the black holes, astronomists had to place radio dishes across the globe.
Because there were images taken from various radio dishes across the globe, astronomists had to be very cautious with how to put these pieces of data together in order to composite the whole picture.
Another challenge astronomists encountered was the complexity of processing the massive amount of data within those locations.
“It took us decades to be able to have the computer capabilities that are able to combine the data within thousands of terabytes,” she said.
With the innovative data processing and telescope technologies, scientists were able to reaffirm the theories put forward in the past.
“That’s what we do in science,” she said. “Sometimes it is hard to cast the idea because the technology isn’t there for us to do the observation. When Galileo found the evidence that the Earth was in the center of the universe, no one had used telescopes to look at the universe at that time.”
Speck said the announcement was not necessarily a well-kept secret, even though there were some actions made prior in order to prevent leaks. “We didn’t know what the result was going to be like,” she said. “We knew something about the black hole was coming but that was about it.”
Speck said she wasn’t necessarily nervous before the image was revealed.
“As a scientist, quite often things don’t look like what you expected or don’t give you the answers you expect,” she said. “If it looks like what you expect, that is confirming what has been studied and build up more understanding. If it doesn’t look like what was expected, there is new science needed to be done.”
She saw it as a win-win situation, either confirming the knowledge scientists have been generating along or an opportunity to generate new knowledge.
Speck said initially the research team was trying to capture the pictures of the black holes in two different galaxies. One is located in Messier 87 galaxy, which is a more distanced galaxy from Earth, and the other is located at the core of our galaxy called Sagittarius A*.
“They couldn’t get an image at Sagittarius A even though we know there is a black hole because we can see most of the stars around it,” Speck said. She was optimistic with the future outcome of the experiment.
“I think this tells us that there is something that is going on inside the core of that black hole within that galaxy which I find interesting,” she said.
She believes this pilot image will serve as the foundation for further processes and eventually scientists will find automatic ways to process the data faster and faster.
“In this case it is confirming rather than refuting,” she said. “This is just one object we have done and we believe there are black holes in the centers of both galaxies. It will help us [further] understand how galaxies work.”
Edited by Emily Wolf | email@example.com