Black hole "wakes up" after 26 years.

[Fenris]

I just thought this was a cool article, and while I pay attention to space "stuff" I had no idea that black holes could go dormant when matter was nearby.

http://www.cnet.com/news/slumbering-black-hole-in-milky-way-roars-back-to-life/

[Shpaget]

I don't see why this is puzzling. There was not much matter for it to eat, so it stopped glowing. Now a rogue asteroid/planet/star wandered too close and started to be torn up and eaten.

It's a big Universe. Weirder stuff happened.

[Nuke]

they spew radiation like crazy when they are feeding. most of the harmful stuff comes from just outside the event horizon where the gravitational stresses are pretty much burn the stuff there in something like a naturally occurring tokamak of sorts.

thats something i noticed in interstellar, there didnt seem to be a star anywhere near gargantua, but i guess the stuff burning around the black hole was enough to illuminate the system.

probibly not accurate so please do tell me if im wrong.

[Shpaget]

The illumination in the Interstellar comes from the radioactive glow, since everything is so insanely irradiated.

[Vanamonde]

Weirder stuff happened.

But this is a weird thing that is happening while we're looking at it, giving us a chance to figure out how and why it's happening. Why was there mass near it that it hadn't already eaten, and that sort of question.

My layman's understanding is that it's unlikely to have been a discrete object, and is more likely to be due to something such as the solar system it's in encountering gas.

[Nuke]

you could also have a star on a highly elliptical orbit. it gets close enough for the black hole to siphon off material near periapsis, but then the black hole goes dormant when the star gets too far away and cant steal material.

[Fenris]

I don't see why this is puzzling. There was not much matter for it to eat, so it stopped glowing. Now a rogue asteroid/planet/star wandered too close and started to be torn up and eaten.

It's a big Universe. Weirder stuff happened.

How was there not much matter for it to eat? V404 Cygni is a binary star system; well, one star and one black hole that orbit each other every 6.5 days, so there was plenty of matter for the black hole to "eat". So why didn't it?

[grawl]

How was there not much matter for it to eat? V404 Cygni is a binary star system; well, one star and one black hole that orbit each other every 6.5 days, so there was plenty of matter for the black hole to "eat". So why didn't it?

Maybe the system reached a point of equilibrium for these 26 years.

[Sampa]

But this is a weird thing that is happening while we're looking at it, giving us a chance to figure out how and why it's happening. Why was there mass near it that it hadn't already eaten, and that sort of question.

My layman's understanding is that it's unlikely to have been a discrete object, and is more likely to be due to something such as the solar system it's in encountering gas.

perhaps there is more to the black holes than just a super dense dead star...