NASA has determined that the pulsar from a binary star system, once visible to observers, has effectively disappeared as the result of a geodetic precession from a nearby space-time warp. Admittedly, that’s a mouthful of scientific jargon.
The international team, including University of British Columbia astronomer Ingrid Stairs, measured the masses of both stars in binary pulsar system J1906. The pulsar spins and emits a lighthouse-like beam of radio waves every 144 milliseconds. It orbits its companion star in a little under four hours.
A pulsar is a “pulsating star” that is likely the remnant of a once massive star that has undergone a supernova which is an event when a star collapses into itself. The pulsar in question is part of the J1906 binary star system. A binary star system in consists of exactly two stars rotating about their common center of mass.
What observers had determined is the J1906 binary star system had a short four-hour rotation. They were using a radio telescope to pick up the highly magnetic signals the pulsar emits and using the information to determine what type of companion star completes the binary star system. It was at this time the pulsar disappeared. Scientists believe the pulsar drew too close to a nearby space-time warp that has now attracted its magnetic impulses preventing them from reaching earth in what is called a “geodetic precession”.
“By precisely tracking the motion of the pulsar, we were able to measure the gravitational interaction between the two highly compact stars with extreme precision,” says Stairs, professor of physics and astronomy at UBC.
“These two stars each weigh more than the Sun, but are still over 100 times closer together than the Earth is to the Sun. The resulting extreme gravity causes many remarkable effects.”
It is believed that once the pulsar completes the current rotation it is in, they will once again be able to observe it. However, it will likely be a different generation of astronomers that will study this particular binary star system. This is because the pulsar isn’t expected to emerge from the warp for another 160 years.
“Through the effects of the immense mutual gravitational pull, the spin axis of the pulsar has now wobbled so much that the beams no longer hit Earth,” explains Joeri van Leeuwen, an astrophysicist at the Netherlands Institute for Radio Astronomy, and University of Amsterdam, who led the study.
“The pulsar is now all but invisible to even the largest telescopes on Earth. This is the first time such a young pulsar has disappeared through precession. Fortunately this cosmic spinning top is expected to wobble back into view, but it might take as long as 160 years.”
As for the two stars in question, they are believed to consist of highly compressed matter with each star weighing more than the sun. At the same time, their proximity to one another is closer than the distance between the earth and the sun. The star system resides 25,000 light years from earth. At this time, not even the largest telescopes on the planet can see the pulsar.
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