High school students locate widest-ever pulsar orbit

A team of high school scientists have discovered an extremely rare pulsar, a neutron star that emits a high-powered beam of electromagnetic radiation.
Not only is the newly discovered star, called J1930-1852, part of a binary star system -- an extremely rare double neutron system, no less -- it also boasts the widest pulsar orbit ever recorded by astronomers.

"Pulsars are some of the most extreme objects in the universe," Joe Swiggum, a graduate student in physics and astronomy at West Virginia University who followed up on the students initial discovery, explained in a press release. "The students' discovery shows one of these objects in a really unique set of circumstances."

Swiggum is the lead author of a new paper on the pulsar; the study was recently accepted for publication in the Astrophysical Journal.

Pulsars form in the wake of the violent deaths experienced by massive stars. They are the product of supernovas. When the massive star explodes, the core is compressed and most of its energy is expelled. What remains is a dense ball of gas, with most its energy concentrated along the axis of its magnetic field.

The concentrated electromagnetic energy of pulsars shoot out lighthouse-like beams of radio waves. The waves pass through space as the collapsed neutron star rotates. These pulses of energy can be picked up by radio telescopes.

High school students discovered this particular pulsar while scanning data collected by the National Science Foundation's Robert C. Byrd Green Bank Telescope, located in West Virginia.

Further analysis revealed the pulsar to be a binary star. Only about 10 percent of pulsars are paired with other stars. And of those, most feature a pulsar and a white dwarf. Just a tiny percentage of those feature a pulsar and another neutron star.

Of about 2,400 pulsars, only 10 are thought to be double neutron star systems. Make that 11.

Because the powerful explosions that create neutron pulsars are so strong and one-sided, they usually are two much for a binary system to handle. The exploding star is likely to be catapulted out into space, the jolt too great for their gravitational lock to survive. That's why double neutron systems are so rare.

Even rarer, however, is such a widely rotating binary system. Most pulsars rotate around their companion in a matter of hours or days. The newly discovered pulsar takes 45 days to circle its neutron companion, covering a distance of more than 32 million miles.

"Its orbit is more than twice as large as that of any previously known double neutron star system," said Swiggum. "The pulsar's parameters give us valuable clues about how a system like this could have formed. Discoveries of outlier systems like J1930-1852 give us a clearer picture of the full range of possibilities in binary evolution."

The students involved in the research, including Cecilia McGough and De'Shang Ray, will receive credit in Swiggum's forthcoming paper.

"This experience taught me that you do not have to be an 'Einstein' to be good at science," said McGough, now an astronomy major and Schreyer Honors College scholar at Penn State University. "What you have to be is focused, passionate, and dedicated to your work."