A team of researchers from DTU Space in Denmark has discovered a neutron star that spins at an incredible speed—716 times per second.
This star, known as 4U 1820-30, is located in the Sagittarius constellation near the center of our Milky Way galaxy. If confirmed, this neutron star would be one of the fastest-spinning objects ever found in the universe.
Neutron stars are the remnants of massive stars that exploded as supernovae. They are extremely dense and compact, packing a mass about 1.4 times that of our Sun into a ball just 12 kilometers wide.
In comparison, our nearest star, Proxima Centauri, is 4.3 light years away, while 4U 1820-30 is located a staggering 26,000 light years away from Earth.
Dr. Gaurava K. Jaisawal, a senior scientist at DTU Space and lead author of the study published in The Astrophysical Journal, explained that the team observed this neutron star using NASA’s NICER X-ray telescope.
NICER is mounted on the International Space Station and uses advanced star-tracking technology developed by DTU Space to point precisely at faraway objects like neutron stars.
The neutron star 4U 1820-30 is part of a unique system called an X-ray binary, where two stars orbit each other closely. The companion to the neutron star is a white dwarf, which is about the size of Earth.
This pair is special because the white dwarf orbits the neutron star every 11 minutes, the shortest known orbital period for such systems.
Due to the neutron star’s intense gravitational pull, it continuously pulls material away from its companion star. Over time, this stolen material accumulates on the neutron star’s surface until a violent thermonuclear burst occurs. These bursts are so powerful that they make the neutron star shine up to 100,000 times brighter than our Sun, releasing enormous amounts of energy.
Dr. Jerome Chenevez, an associate professor at DTU Space and a contributor to the study, explained that studying these bursts helps scientists understand the life cycles of star systems and the formation of elements in the universe.
Between 2017 and 2021, NICER observed 4U 1820-30 and detected 15 thermonuclear X-ray bursts. During one of these bursts, researchers discovered a pattern known as “thermonuclear burst oscillations.” These oscillations matched the neutron star’s spin frequency of 716 times per second, indicating the incredible speed at which it rotates around its center.
If further observations confirm these findings, 4U 1820-30 would match another neutron star, PSR J1748-2446, as one of the fastest-spinning objects known in the universe.
This discovery sheds light on the extreme conditions and fascinating behavior of neutron stars, helping scientists learn more about the life cycles of stars and the dynamics of binary systems. As Dr. Jaisawal noted, this research provides new insights into these distant, powerful, and awe-inspiring objects.
Source: KSR.
