Most people associate Sagittarius with the horoscope for those born around Thanksgiving. In 2018, however, we are all going to learn more about Sagittarius A – a black hole at the center of the Milky Way.
Scientists have begun collecting data that will provide the first image of a black hole and test some of our understandings of the universe
Some Black Holes Can Be Quite Heavy
A black hole is an area of space that contains such a large gravitational pull that nothing, not even light, can escape. Astronomers generally agree that “supermassive” black holes are at the center of most galaxies, including our home in the Milky Way.
These supermassive black holes can have almost a billion times more mass than a standard black hole. Although Sagittarius A is about the size of 4.3 million suns, it is invisible, which makes capturing an image a tall, but not impossible, feat.
An Earth-Sized Telescope to Capture a Galactic Image
In order to obtain an image of Sagittarius A, scientists all over Earth have teamed up to create a virtual radio telescope spanning the entire planet, named Event Horizon.
Since no light can escape a black hole, traditional telescopes cannot capture their images. Radio telescopes, however, can collect electrical signals and translate them into an image.
Since Sagittarius A is so massive, multiple angles and perspectives from all over the globe were needed to properly “view” it.
Crunching Numbers to Stitch An Image
The international project has been collecting and analyzing data on the supermassive black hole all throughout 2017. The data is being compiled by supercomputers into an image of a dark silhouette.
Although a virtual picture of a black shadow might not sound very exciting, the image will provide scientists with a test of Albert Einstein’s theory of general relativity. A 100-year-old theory is finally being tested through observation, which is an amazing feat for science!
As we enter 2018, be prepared to look towards the sky and into the center of astrophysics as we learn more about the universe around us.