Astronomers clock super-fast pulsar speeding through space
A team of astronomers using data from the Fermi Space Telescope and the Very Large Array (VLA) radio telescope have clocked a pulsar hurtling through space at nearly 2.5 million miles (4 million km) per hour. That’s so fast it could travel the distance between Earth and the moon in just six minutes.
The pulsar – named J0002 – is about 6,500 light-years from Earth, speeding through space five times faster than the average pulsar, and faster than 99 percent of those with measured speeds. It will eventually escape our galaxy.
Pulsars are superdense, rapidly spinning neutron stars left behind when a massive star explodes. Pulsar J0002 sports a radio-emitting tail pointing directly back at the center of a shell of debris from the supernova explosion that created it. Frank Schinzel, a scientist at the National Radio Astronomy Observatory (NRAO), presented the discovery at the High Energy Astrophysics Division meeting of the American Astronomical Society in Monterey, California, March 17-21, 2019. Schinzel said in a statement:
Thanks to its narrow dart-like tail and a fortuitous viewing angle, we can trace this pulsar straight back to its birthplace. Further study of this object will help us better understand how these explosions are able to ‘kick’ neutron stars to such high speed.
The pulsar lies about 53 light-years from the center of a supernova remnant called CTB 1. Its rapid motion through interstellar gas results in shock waves that produce the tail of magnetic energy and accelerated particles. The tail extends 13 light-years and clearly points back to the center of CTB 1. Matthew Kerr, of the Naval Research Laboratory, said:
Measuring the pulsar’s motion and tracing it backwards shows that it was born at the center of the remnant, where the supernova explosion occurred.
The explosion debris in the supernova remnant originally expanded faster than the pulsar’s motion. However, the debris was slowed by its encounter with the tenuous material in interstellar space, so the pulsar was able to catch up and overtake it.
The astronomers said that the pulsar apparently caught up with the shell about 5,000 years after the explosion. The system now is seen about 10,000 years after the explosion.
The pulsar’s speed of nearly 700 miles (1,127 km) per second is unusual, the scientists said, with the average pulsar speed only about 150 miles (240 km) per second. Frail said:
This pulsar is moving fast enough that it eventually will escape our Milky Way galaxy.
Exactly how the pulsar was accelerated to such high speed during the supernova explosion remains unclear.
Pulsar J0002 was discovered in 2017 by a citizen-science project called Einstein@Home, which uses time on the computers of volunteers to process Fermi gamma-ray data.
Artist’s animation of Pulsar J0002 speeding away from its birthplace and escaping the shell of debris from the supernova explosion that created it. Via Sophia Dagnello, NRAO/AUI/NSF.
Bottom line: Astronomers find “cannonball pulsar” speeding through space.