Washington Sep 6 (IANS) Astronomers have identified a pulsar spinning at more than 42 000 revolutions per minute making it the second-fastest known.
The new object named PSR J0952-0607 -- or J0952 for short -- is classified as a millisecond pulsar and is located between 3 200 and 5 700 light-years away in the constellation Sextans.
The pulsar contains about 1.4 times the Sun s mass and is orbited every 6.4 hours by a companion star that has been whittled away to less than 20 times the mass of the planet Jupiter according to a study published online in the The Astrophysical Journal Letters.
The discovery was made with the Netherlands-based Low Frequency Array (LOFAR) radio telescope by following up on mysterious high-energy sources mapped out by NASA s Fermi Gamma-ray Space Telescope.
"Roughly a third of the gamma-ray sources found by Fermi have not been detected at other wavelengths " said Elizabeth Ferrara a member of the discovery team at NASA s Goddard Space Center in Greenbelt Maryland.
"Many of these unassociated sources may be pulsars but we often need follow-up from radio observatories to detect the pulses and prove it " Ferrara added.
A pulsar is the core of a massive star that exploded as a supernova. In this stellar remnant also called a neutron star the equivalent mass of half a million Earths is crushed into a magnetised spinning ball.
The rotating magnetic field powers beams of radio waves visible light X-rays and gamma rays. If a beam happens to sweep across Earth astronomers observe regular pulses of emission and classify the object as a pulsar.
The LOFAR discovery also hints at the potential to find a new population of ultra-fast pulsars.
Theorists say pulsars could rotate as fast as 72 000 revolutions per minute before breaking apart yet the fastest spin known -- by PSR J1748-2446ad reaching nearly 43 000 revolutions per minute -- is just 60 per cent of the theoretical maximum.
Perhaps pulsars with faster periods simply can t form. But the gap between theory and observation may also result from the difficulty in detecting the fastest rotators.
--IANS
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