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- Martin Perez
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Astronomers have found that the mysterious object, called PSR J1119-6127, has been caught behaving like two distinct objects. However a star may link two different kinds of stellar remains -a radio pulsar and a magnetar-. The mysterious object itself sometimes is a pulsar, and sometimes it's a magnetar.
A radio pulsar is type of a neutron star, and Magnetars, by contrast, are rabble rousers. Since the 1970s, scientists have treated pulsars and magnetars as two distinct populations of objects. But in the last decade, evidence has emerged that these could be stages in the evolution of a single object.
When this mysterious object was discovered in 2000, it appeared to be a radio pulsar. It was mostly quiet and predictable observed two X-ray bursts and 10 additional bursts of light at lower energies coming from the object by NASA's Fermi and Swift space observatories, and also in the same journal, led by Robert Archibald, looked at the two X-ray bursts. Then they suggested that the pulsar was behaving rebelliously -- like a magnetar. However, Majid said that these X-ray bursts happened because the object's enormous magnetic field got twisted as the object was spinning. Two weeks after the X-ray outburst, Majid and colleagues tracked the object's emissions at radio frequencies, which are much lower in energy than X-rays. They said Within 10 days, something completely changed in the pulsar, and it had started behaving like a normal radio pulsar again.
Some scientists argue that objects like J1119 begin as magnetars and gradually stop outbursting X-rays and gamma rays over time. But others propose the opposite theory: that the radio pulsar comes first and, over time, its magnetic field emerges from the supernova’s rubble, and then the magnetar-like outbursts begin. But it is still unslove, and to help solve this mystery, much as anthropologists study the remains of human ancestors at different stages of evolutionary history, astronomers want to find more “missing link” objects like J1119.
by Dini Dwintika Karuniati
16611042
Article Science
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