Astronomers Spot Dying Star Collapsing into a Black Hole: Corkscrew Nature of Gamma Rays
For the first time ever, scientists have measured the corkscrew nature of a bright flash of light emitted from a dying star collapsing into a black hole. The new findings shed light on an event that happened almost 11 billion years ago.
In this case, the researchers spied Gamma-ray Burst 121024A, a bright flash of light emitted by the dying star. Because the burst was so powerful, the astronomers were able to clearly see it at an extraordinary distance. Yet this burst was unusual; it was circularly polarized.
If light is polarized, it means the waves are moving in a uniform way as they travel. This means that they either bounce up and down or left and right for linear polarization, and corkscrew in a spiral motion for circular polarization.
"Most light in the natural world is unpolarized, the waves are bouncing around at random," said Peter Curan, one of the researchers, in a news release. "But the light from this gamma-ray burst looked like it was part of a 3D movie-it was about 1,000 times more polarized than we expected. This means that the assumptions we've been making about gamma-ray bursts need to be completely reconsidered-assumptions of how electrons are accelerated to the incredible speeds we observe."
In fact, the findings reveal that gamma-ray bursts are far more complex than scientists once believed. While they only last a fraction of a second, these bursts send out as much energy as the sun will over the course of its entire lifetime.
"This is the first time we've found circular polarization in the light from a gamma-ray burst, but we think we'll find it in more bursts in the future, so we can start to pin down what's actually happening when these bright flashes of energy are released," said Curan in a news release.
The findings are published in the journal Nature.