Magnetars are called neutron stars with strong magnetic fields. Usually they do not live very long – about 1 million years, and their initial mass is 40 solar. Until today, scientists knew about the existence of only four magnetars in the Milky Way, but in March 2020, the Swift orbital observatory detected a burst of hard X-ray radiation and a long-lived flash at a distance of 4.8 kiloparsecs.
The signal was studied by an international group of scientists from the Institute of Astrophysics and Space Physics in Milan, as well as scientists from the UK, Germany, Spain, Italy, the USA, and France.
Subsequent observations in this radio range confirmed a ripple with a period of 1.36 seconds. The signal source, called Swift J1818.0-1607, was recognized as the fifth magnetar in the Milky Way.
In addition, the new magnetar can be attributed to a radio-loud source – observations at the Sardinian radio telescope have already recorded strong and short pulsations at a frequency of 1.5 Hz in addition to conventional radiation. This is a fairly rare type of magnetars that combine both fast rotation and a strong magnetic field.