Big black holes have big appetites. The supermassive black holes at the hearts of galaxies can gobble up stars and clouds of gas, growing fatter in the process. But they don't eat everything. In fact, they may push away some of the leftovers, seeding space with the raw materials for stars, planets -- and people.
One of the reasons is that material doesn't fall directly into a black hole. Instead, it forms a disk that swirls around the black hole. As matter circles inside the disk it gets hotter and hotter, producing radiation. The radiation pushes on material at the outer edge of the disk, pushing some of it back into space.
Last year, a team of astronomers reported that the wind from a black hole at the center of a distant galaxy includes carbon, oxygen, and other elements that are crucial for building planets. These elements are also essential for life as we know it. They're racing out at millions of miles an hour, so over millions of years they can penetrate a large volume of space.
And later in the year, a second team studied a black hole that's even farther away. The wind from its disk reaches far outside the host galaxy. And it appears to carry crystals that could have formed in the relatively cool region at the outer edge of the black hole's disk. These small particles could become the building blocks of planets -- important little nuggets that not only escaped a black hole, but were given birth by it.
Script by Damond Benningfield, Copyright 2007
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