Scientists just uncovered the most magnetic star in the universe. The star, known as HD 45166, has a unique, helium-rich spectral signature that hints at an unusual origin.
And in addition to setting records, it might represent the first stage in the lifecycle of a magnetar — a strange type of neutron star.
Related: Bizarre 'failed star' the size of Jupiter is 2,000 degrees hotter than the sun
Located 3,000 light-years from Earth in the constellation Monoceros (the Unicorn), HD 45166 has puzzled scientists for more than a century. The star behaves similarly to a type of extremely bright stellar object known as a Wolf-Rayet star, except that it is smaller, dimmer and has an abnormally high concentration of helium. However, nobody had put forth a satisfactory hypothesis to account for its weird spectral signature — until now.
"I remember having a Eureka moment while reading the literature: 'What if this star is magnetic?'" Tomer Shenar, an astronomer at the University of Amsterdam and co-author of the new study, said in a statement.
Using data from several ground observatories, Shenar and his team discovered that HD 45166 is extremely magnetic — a record-smashing 43,000 times more magnetic than the sun. The researchers suspect that, unlike most massive helium stars, which evolve from red supergiants, HD 45166 formed during a merger between two smaller stars. They also believe that in several million years, it will explode into a modest supernova and re-form as a magnetar.
"This is a very specific scenario," André-Nicolas Chené, an astronomer at the National Science Foundation's National Optical-Infrared Astronomy Research Laboratory and co-author of the study, said in a statement. "It raises the question of how many magnetars come from similar systems and how many come from other types of systems."
In the meantime, this proto-magnetar represents a new type of stellar object never seen before — a massive magnetic helium star.
