A gamma ray event "mystifies astronomers", according to a BBC report. Below are a few quoted details about this event which lasted 6 days, and was 5 times stronger than any other similar phenomenon, even counting that gamma ray bursts are the strongest phenomenon recorded in our universe.
...The cause of the 12 April gamma-ray flare, described at the Third Fermi Symposium in Rome, is a total mystery.It seems to have come from a small area of the famous nebula, which is the wreckage from an exploded star...The gamma-ray emission lasted for some six days, hitting levels 30 times higher than normal and varying at times from hour to hour...
At the heart of the brilliantly coloured gas cloud we can see in visible light, there is a pulsar ... But so far none of the nebula's known components can explain the signal ...What has perplexed astronomers is that these variations in gamma rays are not matched by changes in the emission of other light "colours"..."If you look in optical light, the Crab is very steady; in radio emission, it's very steady; in very, very high-energy gamma rays it's very steady. Only in this part between do we see it varying," [one scientist]... told BBC News...
"To have something that puts almost all of its energy into gamma rays is an unusual thing," he said. "We're looking at a big puzzle and are probably going to need a couple of years to understand it."...
The best guess so far is that in a region near the neutron star, intense magnetic fields become opposed in direction, suddenly re-organising themselves and accelerating close-by particles to near the speed of light....
"It's just so extraordinary that so many telescopes over so many years have been looking at the Crab and it's been constant all that time, and suddenly we discover that it's not," ...[another scientist] told BBC News....
At the heart of the brilliantly coloured gas cloud we can see in visible light, there is a pulsar ... But so far none of the nebula's known components can explain the signal ...What has perplexed astronomers is that these variations in gamma rays are not matched by changes in the emission of other light "colours"..."If you look in optical light, the Crab is very steady; in radio emission, it's very steady; in very, very high-energy gamma rays it's very steady. Only in this part between do we see it varying," [one scientist]... told BBC News...
"To have something that puts almost all of its energy into gamma rays is an unusual thing," he said. "We're looking at a big puzzle and are probably going to need a couple of years to understand it."...
The best guess so far is that in a region near the neutron star, intense magnetic fields become opposed in direction, suddenly re-organising themselves and accelerating close-by particles to near the speed of light....
"It's just so extraordinary that so many telescopes over so many years have been looking at the Crab and it's been constant all that time, and suddenly we discover that it's not," ...[another scientist] told BBC News....
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