Over the summer of this year, NASA's Swift satellite program detected something that defies our understanding of the universe. Seen was a phenomenon titled a hybrid-gamma ray burst, most likely signaling the formation of a new black hole. As one may surmise, a hybrid gamma ray burst is a combination of two classes of gamma ray bursts, but this specific one, named GRB 060614, exhibited features that could not be explained with a simple combination approach.
Gamma ray bursts are the most powerful explosions in the universe, however they only last for a short time and until recently were hard to detect. The Swift program was designed to detect such bursts. Since the discovery of GRB 060614 many of the world's other telescopes, both terrestrial and extra-terrestrial (Hubble, et al), have spent a large amount of time studying the source of GRB 060614. There are two main types of gamma ray bursts: short bursts lasting less than a second or two, and long bursts lasting longer than two seconds. Gamma ray bursts are often a sign that something else is about to happen or has happened; long bursts are often the result of a massive star collapsing into a black hole which can precede a supernova; short bursts, on the other hand, are often the result of two massive bodies merging. GRB 060614 lasted for a whopping 102 seconds, putting it well into the long-burst range, but it was missing the tell-tale sign of a supernova—which often accompanies a long gamma ray burst.
Through measurements of the photons that reached earth shortly after the burst, scientists have found that GRB 060614 behaved much more like a short-bust blast. However, there is currently no theory of merging massive bodies that would explain a burst of the duration of GRB 060614. This leaves scientists in uncharted territory. Some scientists suggest that this may not be an unprecedented event. By searching through old data of past gamma ray bursts (note: this one actually occurred 1.6 billion years ago, so it is very old as well), they believe they have found other hybrid bursts that defy current explanation but do not have the same amount of follow-up examinations as with GRB 060614. As it stands now, scientists are divided over what this was—a very long short burst, or a long burst without the accompanying supernova. Whichever it is, it provides scientists with a new challenge and shows what happens when new evidence reveals that a currently-held theory cannot explain everything. Scientists are regrouping in search of a new explanation that can encompass both our previous knowledge of gamma ray bursts as well as this newly discovered phenomenon. Even in the face of new evidence, science will continue to explore and seek new understanding.
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