Black holes are black spots that are even blacker than the universe itself and devour everything. Because the gravitational force of attraction is so strong that even electromagnetic waves can not escape it. No light – no picture. Or maybe yes? This might change on Wednesday when international scientists present the first results of the Event Horizon Telescope (EHT) project.
That which surrounds black holes is what scientists call the event horizon. And this, in turn, can be observed. The trick is: not to target the black hole, but its environment. As many as six “major press conferences” worldwide are scheduled for Wednesday to present data from the event horizon telescope for the first time. It is nothing less than a review of the general theory of relativity Albert Einstein.
The “black stars” fascinate astronomers for centuries. Indirect methods proved the existence of “omnivores” beyond doubt.
Astronomers suspected that these luminous points in space are directly related to black holes. The term was coined in the mid-1960s by US physicist John Archibald Wheeler. A band of white-hot gas and plasma gives them radiance. What gets inside, goes out.
“The event horizon is not a physical barrier; you can not be in it,” McNamara explains. “When you’re inside, you can not escape because you need infinite energy, and when you’re on the other side, you can – in principle.” At the center of the black hole, all of its mass concentrates in a single point of infinite density and infinite gravitational field, a “singularity.”
The EHT is now for the first time to make the invisible visible. It is a composite of eight giant radio telescopes spread across the globe – Hawaii, Arizona, Spain, Mexico, Chile, and the South Pole. The German Max Planck Institute is also involved in the project.
In April, they were aligned on two black holes at widely spaced locations in the universe: Sagittarius A * (Sag A * for short) in the center of our galaxy and the much larger black hole in the giant galaxy M87 (Messier 87).
Sag A * has a diameter of around 44 million kilometers. What sounds huge takes off from the earth and thus from 26,000 light years (245 trillion kilometers) distance like a golf ball on the moon.
In M87, on the other hand, a gravity monster lurks 1500 times more massive, but it is far more distant; however, the size and distance balance out. Experts and betting shops are tapping Sag A * as the image candidate, because of the Milky Way’s light smog on the way to M87.
Astrophysicists like McNamara are spellbound at General Theory of Relativity – does it last? Never before has she been tested in this dimension. Pioneering research on Einstein’s theory of relativity was presented as early as 2015. Researchers directly observed so-called gravitational waves for the first time, thus confirming a central component of Einstein’s theory from 2015.
The tiny waves are space-time distortions that arise in extremely high-energy events in the universe, such as explosions of giant stars or colliding black holes. Then they spread unchecked through the universe at the speed of light.