Have you seen the news stories about this “unexplained cosmic blast” that NASA’s Swift Satellite captured a few weeks ago? NASA scientists have been checking out this crazy monstrous gamma ray explosion they observed back in March, but that continues to keep shining. Typically these types of cosmic explosions go on for about an hour or so, maybe a little longer, but this one was huge and bright, with very high levels of radiation being emitted from the site.
Well, research is ongoing into this crazy little phenomena, but the general feeling towards this bright burst is that a star in another galaxy has gotten too close to its central black hole, and the black hole tore the star to smithereens – cosmic smithereens, that is. I wonder if that’s the name of the new band by Jack Black and Judd Apatow.
When a star gets torn apart by a black hole like we think this one has, observers will notice a stream of radiation, light, and particles that makes a pretty good light show for a few hours. This one has been going on for a few weeks, which is a bit puzzling, but scientists are thinking that we’re looking directly into the stream of light and particles that the star is giving off. When a star is torn apart like this, a stream of light will be created along the star’s rotational axis – essentially we’re looking into a big bright stream of star destruction. This is crazy pretty, no?
From an article at NASA’s Swift Satellite website:
That same day, astronomers used NASA’s Chandra X-ray Observatory to make a four-hour-long exposure of the puzzling source. The image, which locates the object 10 times more precisely than Swift can, shows that it lies at the center of the galaxy Hubble imaged.
“We know of objects in our own galaxy that can produce repeated bursts, but they are thousands to millions of times less powerful than the bursts we are seeing now. This is truly extraordinary,” said Andrew Fruchter at the Space Telescope Science Institute in Baltimore.
“We have been eagerly awaiting the Hubble observation,” said Neil Gehrels, the lead scientist for Swift at NASA’s Goddard Space Flight Center in Greenbelt, Md. “The fact that the explosion occurred in the center of a galaxy tells us it is most likely associated with a massive black hole. This solves a key question about the mysterious event.”
Most galaxies, including our own, contain central black holes with millions of times the sun’s mass; those in the largest galaxies can be a thousand times larger. The disrupted star probably succumbed to a black hole less massive than the Milky Way’s, which has a mass four million times that of our sun
Astronomers previously have detected stars disrupted by supermassive black holes, but none have shown the X-ray brightness and variability seen in GRB 110328A. The source has repeatedly flared. Since April 3, for example, it has brightened by more than five times.
Scientists think that the X-rays may be coming from matter moving near the speed of light in a particle jet that forms as the star’s gas falls toward the black hole.
“The best explanation at the moment is that we happen to be looking down the barrel of this jet,” said Andrew Levan at the University of Warwick in the United Kingdom, who led the Chandra observations. “When we look straight down these jets, a brightness boost lets us view details we might otherwise miss.”
This brightness increase, which is called relativistic beaming, occurs when matter moving close to the speed of light is viewed nearly head on.
I’m gonna hold off on stocking up for the end of the world another few weeks. 🙂
