Towards the center of our Milky Way galaxy, in the constellation Sagittarius, astronomers have discovered 10 unusual neutron stars called pulsars.
These pulsars are located in a crowded star cluster called Terzan 5, home to hundreds of thousands of stars.
Pulsars are incredibly dense stars that spin rapidly and emit bright pulses of light from their strong magnetic fields.
They serve as beacons for astronomers. Terzan 5, one of the densest places in our galaxy, is already known to host 39 pulsars.
Thanks to the teamwork of the U.S. National Science Foundation’s Green Bank Telescope (NSF GBT) and South Africa’s MeerKAT Telescope, 10 more pulsars have been found, bringing the total to 49.
“It’s very unusual to find exotic new pulsars. But what’s really exciting is the wide variety of such weirdos in a single cluster,” said Scott Ransom, a scientist with the U.S. National Science Foundation National Radio Astronomy Observatory (NSF NRAO).
The discoveries were made by an international team of astronomers from NSF NRAO, the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) (AEI), and the Max Planck Institute for Radio Astronomy.
The MeerKAT Telescope helped locate each pulsar by tracking and timing their rapid spins. This data was matched with twenty years of observations from the NSF GBT, revealing the unusual details of these stars.
“Without the NSF Green Bank Telescope’s archive, we wouldn’t have been able to characterize these pulsars and understand their astrophysics,” added Ransom.
The archival data allowed astronomers to pinpoint the pulsars’ positions, measure their movements, and observe how their orbits changed over time.
Among the discoveries, astronomers found two neutron stars likely orbiting each other as a binary system. Out of 3,600 known pulsars in the galaxy, only 20 have been identified as double neutron-star binaries.
When pulsars pair off, the gravitational pull from one can steal material and energy from the other, causing it to spin faster and become a millisecond pulsar.
This pair could set new records for the fastest spinning pulsar in a double neutron-star system and the longest orbit of its kind. The current fastest spinning pulsar already resides in Terzan 5.
Astronomers also discovered three new rare pulsar “spider” binary systems, in addition to five already known in the cluster. These systems are called Redbacks or Black Widows, depending on their companion stars.
In these systems, a companion star orbits the pulsar, and the pulsar’s energy causes plasma to fill the space between them, slowly dissolving the companion star over time.
The discovery of these strange pulsars helps scientists better understand globular clusters, neutron stars, and even test Einstein’s theory of general relativity. The research team plans to continue searching for more pulsars in Terzan 5, with the help of volunteers.
These discoveries are significant as they expand our knowledge of pulsars and their various categories, offering new insights into the extreme physics of these cosmic phenomena.
Source: National Radio Astronomy Observatory.
