The Italian Almanac

magnetic field

Magnetic Fields Forever

The most powerful magnetic field ever observed in the known universe is located in the Milky Way 6,500 light years from Earth's solar system, according to groundbreaking research by Italian scientists. "It's the discovery we had been expecting for a long time" lead researcher and astrophysicist Andrea Tiengo said.

The findings, which were uncovered by researchers at Pavia's Iuss University and the National Astrophysics Institute (Inaf), were published in the magazine Nature. The study, according to researchers, marks the first time humans have directly witnessed the bizarre cosmic phenomenon known as a magnetar: a neutron star with an extremely powerful magnetic field.

With a mass greater than that of the Sun, magnetars are typically around 20 kilometres in diameter. Their density is even greater. According to scientists, a thimble full of its interior's substance would have a mass of over 100 million tons.

Unlike typical neutron stars, magnetars rotate comparatively slowly, with most completing a rotation once every one to 10 seconds as opposed to less than one second for an average neutron star. Its resulting magnetic field generates very intense bursts of X-rays and gamma rays, with a very short active life of roughly 10,000 years. Scientists estimate there are 30 million or more inactive magnetars in the Milky Way.

The magnetic field Tiengo's team observed is the result of a star that used to occupy the same place. Once it completely decayed, it generated an extremely dense object very similar to a black hole, with a notably large and powerful magnetic field. "What we published is the first direct measurement of a magnetic field of a magnetar," said Tiengo.