Scientists at Fermi lab have found a faster pulsar and more younger than others so lets explore it in detail.
A pulsar is a type of neutron star that emits electromagnetic energy at periodic intervals. A neutron star is the closest thing to a black hole that astronomers can observe directly, crushing half a million times more mass than Earth into a sphere no larger than a city. This matter is so compressed that even a teaspoonful weighs as much as Mount Everest.Astronomers using the Fermi Gamma-ray Space Telescope have found a surprisingly young, powerful and luminous millisecond pulsar. Over the past three years, Fermi has detected more than 100 gamma-ray pulsars and typically the ages of these objects are at least a billion year old. But this new object is just a youngster, born only about 25 million years ago.
The spinning star, a millisecond pulsar called J1823-3021A, is located inside a packed conglomeration of stars called a globular cluster about 27,000 light-years away from Earth in the constellation Sagittarius.The pulsar emits incredibly intense high-energy gamma rays, which the researchers detected and studied using NASA's Fermi Gamma-Ray Space Telescope. Their analysis suggested that the pulsar is just 25 million years old — a baby as far as these stars go, for millisecond pulsars tend to be a billion years old and its extreme brightness and youth challenge current ideas is how a super-bright millisecond pulsars form and it is larger or smaller, and at what speed it can travel.These anomalously energetic millisecond pulsars must be formed at a rate similar to the previously known, more normal millisecond pulsars at least in globular clusters, but possibly in the whole universe as well. In a sense, this pulsar would be the proverbial tip of a hidden new iceberg."One group of pulsars combines incredible density with extreme rotation. The fastest of these so-called millisecond pulsars whirls at 43,000 revolutions per minute. They travel at such speeds because they are gravitationally bound in binary systems with normal stars. During part of their stellar lives, gas flows from the normal star to the pulsar. Over time, the impact of this falling gas gradually spins up the pulsar's rotation. The strong magnetic fields and rapid rotation of pulsars cause them to emit powerful beams of energy, from radio waves to gamma rays. Because the star is transferring rotational energy to the pulsar, the pulsar's spin slows after this transfer is completed.Fermi's Large Area Telescope (LAT) showed that eleven globular clusters emit gamma rays, the cumulative emission of dozens of millisecond pulsars too faint for even Fermi to detect individually. But that's not the case for NGC 6624.That pulsar is J1823-3021A, which is spinning at about 11,100 revolutions per minute, or one complete turn every 5.44 milliseconds. The team didn't discover the pulsar; it has been known since the 1990s. But its incredible gamma-ray brightness remained undetected until now.J1823-3021A also appears to have a much stronger magnetic field than other millisecond pulsars. J1823−3021A was previously identified as a pulsar by its radio emission, yet of the nine new pulsars, none are millisecond pulsars, and only one was later found to emit radio waves.
[via: MSNBC]
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