Confusing, isn't it? A black hole is supposed to be, well, black, no?

Soprano

Village Elder
#1
black-hole-event-horizon-01.adapt_.885.1-580x386.jpg Milky Way’s Black Hole Just Flared, Growing 75 Times as Bright for a Few Hours
Even though the black hole at the center of the Milky Way is a monster, it’s still rather quiet. Called Sagittarius A*, it’s about 4.6 million times more massive than our Sun. Usually, it’s a brooding behemoth. But scientists observing Sgr. A* with the Keck Telescope just watched as its brightness bloomed to over 75 times normal for a few hours.
The flaring is not visible in optical light. It’s all happening in the near-infrared, the portion of the infrared spectrum closest to optical light. Astronomers have been watching Sgr. A* for 20 years, and though the black hole does have some variability in its output, this 75 times normal flaring event is like nothing astronomers have observed before. This peak was over twice as bright as the previous peak flux level.
These results are being reported in the Astrophysical Journal Letters in a paper titled “Unprecedented variability of Sgr A* in NIR“, and is available at the pre-press site arXiv.org. The lead author is Tuan Do, an astronomer at UCLA.
 

Soprano

Village Elder
#11
@gashwin unaipata vizuri sana! Wengine wanaona waelezee tu for the sake of it.

A black hole. Walituambia nothing can escape from it's gravitational capture, not even light itself. That's why it is a black hole. Because no light comes from there. For something to be bright, there basically have to be some light emanating from or reflected by it. How then can a black hole be said to be bright?
 

kalel

Village Elder
#14
@gashwin unaipata vizuri sana! Wengine wanaona waelezee tu for the sake of it.

A black hole. Walituambia nothing can escape from it's gravitational capture, not even light itself. That's why it is a black hole. Because no light comes from there. For something to be bright, there basically have to be some light emanating from or reflected by it. How then can a black hole be said to be bright?
Ilekitu ilifanya wasema kuna black hole ndio imebrighten as a direct result of something the black hole has done..kapish
 
#15
@gashwin unaipata vizuri sana! Wengine wanaona waelezee tu for the sake of it.

A black hole. Walituambia nothing can escape from it's gravitational capture, not even light itself. That's why it is a black hole. Because no light comes from there. For something to be bright, there basically have to be some light emanating from or reflected by it. How then can a black hole be said to be bright?
There's smth called Hawking radiation, happens when black holes are evaporating. Where do you get these articles reported by sensational writers who make unscientific claims and don't bother doing more research. And they write it like it just happened yesterday when the light probably took years to arrive on earth.
 
#19
View attachment 253961 Milky Way’s Black Hole Just Flared, Growing 75 Times as Bright for a Few Hours
Even though the black hole at the center of the Milky Way is a monster, it’s still rather quiet. Called Sagittarius A*, it’s about 4.6 million times more massive than our Sun. Usually, it’s a brooding behemoth. But scientists observing Sgr. A* with the Keck Telescope just watched as its brightness bloomed to over 75 times normal for a few hours.
The flaring is not visible in optical light. It’s all happening in the near-infrared, the portion of the infrared spectrum closest to optical light. Astronomers have been watching Sgr. A* for 20 years, and though the black hole does have some variability in its output, this 75 times normal flaring event is like nothing astronomers have observed before. This peak was over twice as bright as the previous peak flux level.
These results are being reported in the Astrophysical Journal Letters in a paper titled “Unprecedented variability of Sgr A* in NIR“, and is available at the pre-press site arXiv.org. The lead author is Tuan Do, an astronomer at UCLA.
Since Sagittarious A is 25,000 light years from earth, does it mean the flare happened 25,000 years ago.
I've never understood clearly, but these people make it sound like it just happened today.
 

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