Star Reveals Magnetic Field Around Milky Way's Supermassive Black Hole

Astronomers have found something new in the center of our Milky Way Galaxy--a magnetar that has an extremely strong magnetic field. This pulsar has now allowed researchers to investigate the direct vicinity of the black hole at the center of our galaxy, revealing a little bit more about it.

A magnetar is a type of neutron star, and a category of pulsar, with an extremely powerful magnetic field, the decay of which powers the emission of high-energy electromagnetic radiation, particularly X-rays and gamma rays. In this case, the scientists discovered the pulsar orbiting the candidate supermassive black hole at the center of our galaxy. Pulsars can act as extremely precise atomic clocks, measuring the properties of space and time around the object. In fact, scientists could potentially use this pulsar to see if Einstein's theory of General Relativity can hold up to the strictest tests.

After the discovering of this flaring X-ray source, the scientists decided to conduct a radio follow-up program in order to confirm the findings and learn a little bit more about the pulsar.

"As soon as we heard about the discovery of regular pulsations with the NuSTAR telescope we pointed the Effelsberge 100-m dish in the direction of the Galactic center," said Ralph Eatough, the lead author of the new study, in a news release. "On our first attempt the pulsar was not clearly visible, but some pulsars are stubborn and require a few observations to be detected. The seconde time we looked, the pulsar had become very active in the radio band and was very bright. I could hardly believe that we had finally detected a pulsar in the Galactic center!"

While the Effelsberg radio telescope has been observing the Galactic center for about 40 years, it's only now that it's detected the first radio pulsar. Yet this new finding could open the way for future observations. For example, the magnetic field strength in the vicinity of the black hole at the center of our galaxy is an important property. The black hole is gradually swallowing its surroundings in a process called accretion. Magnetic fields caused by this in-falling gas can influence the structure and dynamics of this accretion flow. The pulsar can help with measurements of the strength of the magnetic field at the beginning of the accretion flow to the central black hole.

The findings reveal a little bit more about the center of our galaxy. In addition, they show how with time and patience, watching the skies eventually pays off. The discovery of this magnetar could pave the way for future discoveries.

The findings are published in the journal Astrophysical Journal Letters.