A Slow Explosion
			
		
		
		
			Why would a 
gamma ray burst fade so slowly?  
This behavior, recorded last October, 
is considered a new clue into the cause of 
gamma-ray bursts, 
the most powerful explosions known in the universe.  
The burst, first detected by the orbiting 
HETE satellite 
and later tracked by numerous ground-based telescopes, 
showed an unusually slow and tumultuous decay in visible light.  
Speculations on the cause of the 
unusual light curve include a blast wave striking a 
windy circumburst medium, 
a blast wave energetically refreshed by a faster outgoing shock, 
and non-uniformity in a fast moving jet.  
Pictured above is the massive 
Wolf-Rayet star WR124, a star itself undergoing a 
slow explosion 
by producing a very powerful but tumultuous 
wind.  
Popular candidate progenitor sources for 
GRBs include 
supernova or 
hypernova explosions from massive stars, 
possibly ones with similarities to 
Wolf-Rayet stars.