Milky Way Fireworks
The center of the Milky Way galaxy may be about to set off some fireworks. An object known as G2 is plunging toward the black hole at the galaxy’s heart. It’s expected to pass closest to the black hole later this month, and astronomers are watching to see if the encounter produces a lightshow.
The black hole is four million times as massive as the Sun. Its gravity is so powerful that nothing can escape from it, including light. But matter around the black hole can be heated to millions of degrees, producing enormous amounts of energy.
For the most part, there’s not much around the black hole to see. There’s an occasional outburst when a bit of gas or some rocky debris spirals into the black hole, but otherwise it’s pretty quiet. There’s evidence of some big outbursts in centuries past, but none since astronomers have been able to watch.
Right now, they’re keeping an eye on the black hole with quite a few telescopes on the ground and in space for G2’s close approach. G2 is probably a cloud of gas. But it could also be a ring of gas, or perhaps a star that’s surrounded by a disk of gas and dust.
Whatever it is, it’ll be pulled apart by the black hole’s gravitational pull. That will heat the material, perhaps causing it to glow. Some of the gas could be pulled into the black hole, triggering a bright outburst that could last for months or years — fireworks from a black hole.
Script by Damond Benningfield, Copyright 2014
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