First ever picture of a black hole may be revealed this week

[Valin]

New Scientist

Chelsea Whyte

Apr 8 2019

What is it like to stare directly into the dark heart of our galaxy? We’re about to find out. The team at the Event Horizon Telescope (EHT) – a network of telescopes around the globe working together to make an image of a black hole – is going to release its first results on 10 April.

Taking a picture of a black hole is difficult because they don’t emit or reflect any light. So, what are we going to see? “They’re trying to get an image of the black hole’s shadow,” says Avi Loeb at Harvard University. Black holes are surrounded by bright material glowing as it falls in to their maw, and part of this material should be obscured by the black hole itself.

“It’s very different from the shadow cast by an opaque object because a black hole isn’t opaque, it’s absorbing light,” says Loeb. “As a result, we should see a dark inner region surrounded by a sliver of light that looks like a crescent moon.”

That crescent shape is predicted by Albert Einstein’s theory of special relativity, which says that matter moving towards us will look brighter and anything moving away would be dimmed. We may also see the effects of the immense gravity of a black hole, says Loeb, in the form of gravitational lensing which can bend light as it passes nearby.

EHT is targeting two black holes, the biggest in the sky from our point of view. The first is Sagittarius A*, the supermassive black hole at the centre of the Milky Way, while the second is an even larger black hole at the centre of the Messier 87 galaxy, found in the constellation Virgo.

(Snip)

[Valin]

 

[Valin]

 

[Valin]

 

[Valin]

3 Huge Questions the Black Hole Image Didn't Answer

Rafi Letzter, Staff Writer

April 10, 2019

An international network of radio telescopes has produced the first-ever close-up image of a black hole's shadow, which scientists revealed this morning (April 10). The collaboration, called the Event Horizon Telescope, confirmed decades of predictions of how light would behave around these dark objects, and set the stage for a new era of black hole astronomy.

"From a scale of zero to amazing, it was amazing," said Erin Bonning, an astrophysicist and black hole researcher at Emory University who was not involved in the imaging effort.

"That said, it was what I expected," she told Live Science.

The announcement, teased for about a week and a half in advance, managed to be both incredibly exciting and almost completely devoid of surprising details or new physics. Physics didn't break down. No unexpected features of black holes were revealed. The image itself was almost a perfect match for illustrations of black holes we're used to seeing in science and pop culture. The big difference is that it's a whole lot blurrier. [9 Weird Facts About Black Holes]

There were several important questions related to black holes that remained unresolved, however, Bonning said.

(Snip)

[Valin]