Object mistaken as a galaxy is actually a black hole pointed directly at Earth

[admin]

An object once thought to be a radio galaxy is actually an active black hole that changed angles to point directly at Earth, new research suggests.

Object mistaken as a galaxy is actually a black hole pointed directly at Earth : Read more

 

[jvdk]

I don't know for sure, but I doubt the distance is 4 million light-years. I think you've forgotten a few zeroes.

 

[Oksana]

Вы правы, есть ошибка. Эта галактика удалена от нас на 656 844 372 световых года. 4 миллиона световых лет его диаметр. original article here https://www.ras.ac.uk/news-and-press/news/galaxy-changes-classification-jet-changes-direction

 

[Oksana]

I don't know for sure, but I doubt the distance is 4 million light-years. I think you've forgotten a few zeroes.

You are right, there is a mistake. This galaxy is 656,844,372 light years away from us. 4 million light years its diameter. original article here https://www.ras.ac.uk/news-and-press/news/galaxy-changes-classification-jet-changes-direction

 

[A_Raybold]

Вы правы, есть ошибка. Эта галактика удалена от нас на 656 844 372 световых года. 4 миллиона световых лет его диаметр. original article here https://www.ras.ac.uk/news-and-press/news/galaxy-changes-classification-jet-changes-direction

Even after reading the press release you have linked to (thanks for that!) I am a bit confused about what is going on here.

At least three things are clear to me: firstly, this was once classified as simply a radio galaxy, but now is classified as a blazar (or, more precisely, a radio galaxy with a blazar at its core, where a blazar is a supermassive black hole emitting a jet in our direction.) Secondly, the black hole previously emitted its jets approximately perpendicular to our line-of-sight, but has now rotated so one is pointing at us. Thirdly, the earlier orientation of the jets are revealed by two lobes of gas that have been detected in the vicinity of this galaxy.

Are we supposed to conclude that the black hole changed its orientation since it was first discovered and classified as an ordinary radio galaxy? That cannot have been more than a few decades ago at most, yet the change in angular momentum needed to reorient a rapidly rotating supermassive black hole through approximately 90 degrees would have to be enormous. The article suggests that a galactic merger could do it, yet they require hundreds of millions of years (if not billions) to complete.

My best guess is that the changing classification of the galaxy and the changing orientation of its black hole are essentially unrelated facts about it.

 

[Allan Brewer]

"...a supermassive black hole spewing radiation at near light speed... " Since radiation always travels at actual light-speed there is something wrong here. Maybe the author means "spewing particles at near light-speed"?