If that's right, the researchers say, a dense cluster of massive stars will become visible at the site of the explosion when 2006gy fades in a year or so.
Dying Alone
The alternate model proposed by Woosley and his colleagues has the spectacular clash happening not between multiple stars but between remnants of sequential, explosive pulses from a single dying star.
As such a massive star's life neared the end, it would have entered a phase of burning that was insufficient to fully incinerate its core. But the burning would have been strong enough to cause explosions that ejected out shells of material many times the mass of our sun, the researchers say.
The core would then have contracted, regrouped, and exploded again. The new explosion would have released massive amounts of material, which would have collided with matter from the first explosion.
Such a bombardment could explain the extraordinarily bright display in 2006gy, Woosley said. He and his colleagues have dubbed it a "hypernova."
"Our model is in good agreement with the observed light curve for SN 2006gy and also shows that some massive stars can produce more than one supernova-like outburst," Woosley and his colleagues wrote.
Enduring Mystery
Both theories are mere speculation for now—but that may change as 2006gy clears up over the years.
Both sets of researchers, for example, say the supernova could eventually collapse into a black hole equally impressive in its mass.
Woosley also suggests, however, that if 2006gy didn't burn up its entire helium core during this explosion, it may regroup and explode again.
He said that the other paper "calculates no light curve, so it is only a speculation about how a progenitor star may have formed."
Most massive stars are born and die in clusters, he added, so if a cluster is visible after 2006gy fades, that's not necessarily evidence that the two-star collision model is best.
Portegies Zwart said the jury is still out on which explanation rings truer.
"To what extent the two theories are really consequences of each other, and if they really explain the same phenomenon in the end is hard to say," he pointed out.
"But I'm sure more research will be done in this direction."
Free Email News Updates
Sign up for our Inside National Geographic newsletter. Every two weeks we'll send you our top stories and pictures (see sample).
|
SOURCES AND RELATED WEB SITES
|
