Late last week we told you about those unexplained — but extremely powerful — radio bursts that originated from another galaxy. A number of theories have been proposed to account for the phenomenon, but there’s one in particular that caught our attention: Blitzars — the final stage of a supramassive neutron star.
Cosmologists have been scratching their heads since first detecting fast radio bursts (FRBs) back in 2007 (Lorimer and Narkevic). In just a few milliseconds, each FRB releases as much energy as the sun emits in 300,000 years.
Some of the theories that have been proposed include colliding magnetars (neutron stars with super-strong magnetic fields), evaporating black holes, gamma ray bursts that involve a supernova, or an entirely new type of high-energy astrophysical event. And indeed, it could very well be something completely new to science.
Such is the thinking of astrophysicists Heino Falcke (Radboud University in Nijmegen, Netherlands) and Luciano Rezzolla (Max Planck Institute for Gravitational Physics in Potsdam, Germany) who have proposed a new type of astronomical phenomenon: The blitzar.
Blitzars begin when an overweight neutron star (the remnant of a supernova explosion) resists the urge to turn into a black hole on account of its rapid rotation; its spin is so fast that its centrifugal force prevents a collapse.
At this stage it’s a rather unremarkable, but doomed, pulsar. After a few million years of this, the pulsar’s strong magnetic field steadily radiates energy away, which eventually causes the spin to slow down. Eventually it succumbs to the force of gravity and turns into a black hole.
But at the exact moment of this celestial conversion, an exterior portion of the pulsar’s magnetic field is cut off from its (now vanished) source. This magnetic energy is transformed into a burst of wide spectrum radio energy. Falcke and Rezzolla liken this event to the snapping of rubber bands — an effect that produces the observed giant radio flashes. At the same time, other types of radiation cannot escape the gravitational collapse.
Now, this is all highly speculative, of course. And the study has yet to be peer reviewed. But you can check it out for yourself at arXiv: “Fast radio bursts: the last sign of supramassive neutron stars.”