On March 28, NASA’s Swift gamma ray burst observatory saw a tremendous flash of light some four billion light years away. While it was initially chalked up to an exploding star, new analysis seems to indicate that a star may have been
On March 28, NASA’s Swift gamma ray burst observatory saw a tremendous flash of light some four billion light years away. While it was initially chalked up to an exploding star, new analysis seems to indicate that a star may have been pulled into a black hole. If true, this would be only the second time this has been observed.
Because of the distance, we can never be certain about what happened to the star. However, there’s quite a bit of evidence that the star met its end in the belly of a black hole. Normally, gamma ray bursts occur when a large star collapses and becomes a black hole. But this time, the intensity of the light grew and faded over time, which would fit scientists understanding of how black holes consume matter.
In this case, it’s believed that the star was orbiting a black hole and because of an encounter with another body or a decaying orbit, fell in. The Bad Astronomy blog describes the catastrophic death of the star once it was too close to the black hole.
Black holes have incredibly strong gravity, of course, but that gravity gets weaker with distance. Stars are big, a million or more kilometers across, and that means one side of the star was substantially closer to the black hole than the other, so the near side felt a stronger pull of gravity than the far side of the star. [...] A star is held together by its own gravity. As the star in question here inched closer to the black hole, the force stretching the star got stronger, and at some point overcame its internal gravity.
What this all means is that the star was stretched and ripped apart, the material swirling around the black hole sending out huge amounts of energy until it finally abated.
Observers are still watching the area around where the amazing burst occurred. If it was caused by a star being devoured, then it should brighten again soon.