“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,” says Andrew Lyne, professor of physics at the University of Manchester.
“Ultimately, we realized these peculiarities were caused by motion around another star, making this the longest-period binary system containing a radio pulsar.”
The pulsar is in a binary system with nearby MT91 213, a massive star in the constellation of Cygnus, 15 times the mass of the Sun and 10,000 times brighter.
Every 25 years the pulsar completes an elongated orbit around the partner star, much longer than any previously known pulsar-massive star binary.
Credits: NASA’s Goddard Space Flight Center
The star is embedded in a large disk of dust and gas, caused by the Sun’s intense stellar winds.
When the pulsar passes closest to MT91 213 it travels through the star’s dust disk and this is next due to happen in 2018 and scientists are expecting to see fireworks.
“This forewarning of the energetic fireworks expected at closest approach in three years’ time allows us to prepare to study the system across the entire electromagnetic spectrum with the largest telescopes,” says Ben Stappers, a professor of astrophysics at the University of Manchester.