The meeting between a stellar remnant the size of a city and one of the brightest stars in the galaxy will set off some high-energy fireworks in early 2018, according to NASA.
The remnant, known as J2032 for short, is the crushed core of a heavyweight star that has previously detonated in a supernova explosion. Found by NASA’s Fermi Space Telescope in 2009, the pulsar is a highly magnetic ball about 19.31 kilometres (12 miles) across and weighs in at almost twice the Sun’s mass. Despite its heft, the pulsar spins rapidly, emitting strong magnetic fields to produce a lighthouse-like beam that’s detectable when it sweeps our way.
However, by keeping tabs on the object for four years, a team of astronomers at the University of Manchester’s Jodrell Bank Centre for Astrophysics noticed something very odd about J2032. “We detected strange variations in the rotation and the rate at which the rotation slows down – behaviour we have not seen in any other isolated pulsar,” explains physicist Andrew Lyne. “Ultimately, we realised these peculiarities were caused by motion around another star, making this the longest-period binary system containing a radio pulsar.”
The culprit tugging on the pulsar is massive Be star, MT91 213. With an incredible mass of 15 times the mass of the Sun and shining 10,000 times brighter than our nearest star, MT91 213 is embedded in a large disc of gas and dust and unleashes strong outflows known as stellar winds.
J2032 orbits MT91 213 on an elongated path that lasts around 25 years. The pulsar gets up close and personal once every lap it completes. However, in 2018, things are about to change: J2032 will plough through the Be star’s surrounding disc, triggering cosmic fireworks. Usefully, it will serve as a probe to enable them to measure the MT91 213’s gravity, magnetic field as well as its stellar wind along with its disc’s properties.
“This forewarning of the energetic fireworks expected at closest approach in [less than] three years’ time allows us to prepare to study the system across the entire electromagnetic spectrum with the largest telescopes,” adds Ben Stappers, also at the University of Manchester.