A suite of space-based telescopes operated by NASA and the European Space Agency have discovered the youngest known magnetar to date. At just 240 years old, this extreme, cosmic infant could help astronomers understand how these dead, dense stars come to be and how they evolve.
In a study, published in The Astrophysical Journal Letters on Wednesday, researcher describe Swift J1818.0-1607, a very young magnetar first spotted by NASA’s Neil Gehrel’s Swift Observatory on March 12 after it let out a mighty, explosive burst of X-rays. Magnetars are a rare kind of neutron star (the collapsed cores of huge stars) with extreme magnetic fields. They pack a huge amount of mass into a tiny space, which generates a huge amount of weird physical phenomena. Their magnetic fields can be up to 1,000 times stronger than your regular, run-of-the-mill neutron star.
This particularly magnetar is only around 16,000 light-years from the Earth — practically our backyard — and located in the constellation Sagittarius. Astronomers have only detected a few dozen magnetars and none have ever been detected so shortly after they have formed.
“This object is showing us an earlier time in a magnetar’s life than we’ve ever seen before, very shortly after its formation,” said Nanda Rea, an astronomer at the Institute of Space Sciences in Barcelona and co-author on the study, in a release.
The Swift Observatory was the first to spot J1818.0-1607. Astronomers followed-up Swift’s observations with the European Space Agency’s XMM-Newton observatory, NASA’s NuSTAR telescope and the ground-based Sardinia Radio Telescope in Italy to reveal more about this rare star’s features. That helped pin down an age: 240. If further observations of the magnetar’s spin reinforce this hypothesis, it will be the youngest ever magnetar found.
“What’s amazing about [magnetars] is they’re quite diverse as a population,” said Victoria Kaspi, an astronomer at McGill University in Montreal who was not involved with the study. “They’re very strange and very rare and I don’t think we’ve seen the full range of possibilities.”
Keeping an eye on the young magnetar will help add to a growing body of research about the enigmatic and uncommon phenomena. Astronomers may be able to chart the changes that magnetar’s undergo as they move from infancy to adulthood — and how aging affects their properties and emissions.
Magnetars are also one of the prime suspects in— brief radio signals that flare to life and quickly disappear. It’s hypothesized the extreme environments around such stars may be flinging these strange signals at the Earth.