(Bad Astronomy) NGC 3783 is a spectacular face-on spiral galaxy about 125 million light-years from us. In its exact center is a supermassive black hole, some 30 million times heftier than our Sun (about 7 times more massive than Sgr A*, the central black hole in our Milky Way). It’s actively feeding, meaning material like gas is falling into it. As it does, this matter forms an accretion disk that gets very hot, and glows brightly.
These disks are made of ionized gas, material with electrons stripped away from their parent atoms. Moving charged particles make a magnetic field, so the NGC 3783 disk has a powerful field embedded in it.
The magnetic field lines — the loops you can see when, for example, iron filings are spread around a bar magnet — store a vast amount of energy, and aren’t always stable. I like the analogy of a bag full of giant metal springs that have been bent and the ends very gently connected. If one snaps it
sproings straight and releases its energy, slapping into other springs and triggering them too, generating a cascade you don’t want to stick your hand in. You get a huge burst of energy.
Same thing here. The magnetic field lines in the accretion disk can snap and release their energy, making a runaway effect, and it can be soul-chillingly powerful blast, outshining the entire galaxy at some wavelengths. In 2024 just such a flare was seen from NGC 3783, a blast of X-rays so powerful it was equal to 10 billion times the Sun’s luminosity! [link to journal paper] :
https://www.aanda.org/articles/aa/full_ ... tmosphere
But it did more than that: the data indicate that the explosion also sent out a huge blast of subatomic particles, what we call a wind, accelerated to immense speed. The wind velocity was measured to be a staggering 57,000 kilometers per second, or about
one-fifth the speed of light! To get an idea of how much energy was involved in this, only about 10% of the energy went into the X-ray flare, the other 90% went into blasting out this material. So,
90 billion times the energy the Sun produces every second.
