Astronomers spot light behind a black hole for the first time, reaffirming Einstein's...

Shawn Knight

Posts: 13,498   +132
Staff member
Something to look forward to: An international team of astronomers have observed light from behind a black hole for the first time. Future observatories, like the Advanced Telescope for High Energy Astrophysics (Athena) should provider even higher resolution images with much shorter observation times.1

Led by Stanford University’s Dan Wilkins, the team focused on a black hole that is 10 million times as massive as our sun and located 1,800 million light years away in a galaxy called I Zwicky.

Armed with the European Space Agency’s XMM-Newton and NASA’s NuSTAR space telescopes, the astronomers observed bright flares of X-ray light coming from around the black hole. The X-ray flares echoed off of gas that was falling into the black hole, and as the flares were subsiding, the telescopes were remarkably able to pick up smaller flashes of X-rays that were different “colors.” These were the echoes bouncing off the gas behind the black hole.

“Any light that goes into that black hole doesn’t come out, so we shouldn’t be able to see anything that’s behind the black hole,” Wilkins said. “The reason we can see that is because that black hole is warping space, bending light and twisting magnetic fields around itself,” he added.

The black hole’s gravitational pull is responsible for the warping of space.

This is the first time that astronomers have directly observed light from behind a black hole, and it also matches Einstein’s theory of general relativity, yet again confirming his predictions.

The team’s findings were recently published in the scientific journal Nature.

Image credit Dan Wilkins

Permalink to story.

 

polord

Posts: 90   +73
Our galaxy has a diameter about 110.000 lightyear, but the closest galaxy is more then 1,8 million lightyear, or am I wrong?
 

QuantumPhysics

Posts: 5,282   +5,999
Our galaxy has a diameter about 110.000 lightyear, but the closest galaxy is more then 1,8 million lightyear, or am I wrong?


The closest known galaxy to us is the Canis Major Dwarf Galaxy, at 236,000,000,000,000,000 km (25,000 light years) from the Sun.
 

yRaz

Posts: 3,850   +4,030
Our galaxy has a diameter about 110.000 lightyear, but the closest galaxy is more then 1,8 million lightyear, or am I wrong?
No, you aren't wrong, but even though this blackhole is farther away it is so massive that it's larger in the sky than the one at the center of our galaxy
 

scavengerspc

Posts: 1,667   +1,726
TechSpot Elite
So how many years has it been that we have heard that a black hole is so dense even light gets drawn in and can't escape. So how do we see the light behind it?

Or am I way off the mark? My kids would point out it's not the first time so, you know.
 
Last edited:

scavengerspc

Posts: 1,667   +1,726
TechSpot Elite
Hope this helps:

Thanks man. I actually get it now. And thanks for finding that. I couldn't find anything that directly give an explanation of what I was curious about.

Funny though. If I had heard the word "Schwarzschild" before, I probably would have thought of Space Balls. Anyway, the light we see “behind” it has already been bent, and then it goes out into space (3:50 in the video)........My head hurts.

But seriously, (y) (Y)
 
Last edited:

Puiu

Posts: 4,928   +3,796
TechSpot Elite
Thanks man. I actually get it now. And thanks for finding that. I couldn't find anything that directly give an explanation of what I was curious about.

Funny though. If I had heard the word "Schwarzschild" before, I probably would have thought of Space Balls. Anyway, the light we see “behind” it has already been bent, and then it goes out into space (3:50 in the video)........My head hurts.

But seriously, (y) (Y)
Veritasium is one of my favourite science channels alongside, Thoughty2 and Vsauce.
 

Avro Arrow

Posts: 1,800   +2,152
TechSpot Elite
This isn't really a surprise. Physicists prove their theories with mathematics long before we are able to observe the actual phenomena. The black hole was first theorised back in the 1700s but we first saw one over 200 years later. The universe operates purely on the principles of mathematics. This is why the first thing that a physicist must do to gain support for a theory is "show the math" because if the math works, it works, end of story.
 

Avro Arrow

Posts: 1,800   +2,152
TechSpot Elite
Our galaxy has a diameter about 110.000 lightyear, but the closest galaxy is more then 1,8 million lightyear, or am I wrong?
You're close. Our galaxy is about 105,000LY in diameter but the closest galaxy is over 2,500,000LY away. That's changing though because it's Andromeda and one day, Andromeda and Milky Way will collide. It would really suck if it turned out that Andromeda is made of antimatter. :laughing:

So how many years has it been that we have heard that a black hole is so dense even light gets drawn in and can't escape. So how do we see the light behind it?

Or am I way off the mark? My kids would point out it's not the first time so, you know.
It's because the light that we see isn't close enough to be unable to escape. Some of the light that travels near a black hole does indeed go into it but not all. Only the light that gets close enough to be sucked in gets sucked in.

Photon streams that are just outside of the "no-escape" range of the hole's gravity get their paths bent around the black hole. Those photons would normally not be visible to us because they'd be going off in some other direction without the black hole's gravity there to "aim" them at us. The images from behind a black hole are therefore distorted and that's why black holes have halos when they're eclipsing a potent source of light. Scientists call this "gravitational lensing" and it's apparently visible around all major sources of gravity. It's not just light that bends, it's all forms of electromagnetic streams from radio waves to gamma rays.

If you want to know more, watch PBS Space Time on YouTube. It's pretty incredible stuff and I got addicted to watching them years ago. They talk about theoretical universe models, cosmic background microwave radiation, spectral classes of stars, black holes, white holes, antimatter, neutron stars, hawking radiation, nebulae, quantum mechanics, the relationship between physics and math, the effects of gravity upon the passage of time, the end of the universe (when there is no energy left), etc. It makes you feel smaller than a speck of dust but it's also amazing to see what makes up our reality and just how bat$hit-crazy it all is. It messes with your mind because it makes you see things differently than you did before. You start to see what "makes up the matrix" all around you.
 

Shadowboxer

Posts: 1,717   +1,322
This isn't really a surprise. Physicists prove their theories with mathematics long before we are able to observe the actual phenomena. The black hole was first theorised back in the 1700s but we first saw one over 200 years later. The universe operates purely on the principles of mathematics. This is why the first thing that a physicist must do to gain support for a theory is "show the math" because if the math works, it works, end of story.

That really isn’t the end of the story at all! Maths is not the perfect model for physics but it’s the best we have yet.
 

CybaGirl

Posts: 69   +29
the end of the universe (when there is no energy left), etc.

Thanks so much for the link and I will be checking it. I so love all this stuff and love reading and watching things about it.

When you say the end of the universe (when there is no energy left) how long do you think this will take?

Where does this current energy come from?

What do you think is outside of the universe as this is something I have always thought about?

I mean I have read many articles about this. But I still believe there has to be something outside of the universe as told in the movie Event Horizon. After all everything is inside something don't you think?

I also wonder if the universe is round like a planet or is it just flat so to speak and where does it end if at all?

I guess I have so many questions but find it difficult to connect with like minded people and talk about such things.
 

Danny101

Posts: 1,848   +794
'10 million times as massive as our sun'

Well it's a good thing it's located 1,800 million light years away.