A space telescope scanning the sky for gamma rays has added hundreds of powerful new dead stars to its catalogue. The addition of 294 previously unidentified stars means that Fermi’s catalog of gamma-ray pulsars now includes more than 340 objects; This is a significant advance since observations with the Fermi Large Area Telescope began in 2008, when fewer than 10 pulsars were known.

The recently published third catalog of gamma-ray pulsars from the Large Fermi Telescope is a veritable treasure trove of information that will help us understand these mysterious objects.

“Pulsars are relevant to a wide range of astrophysics research, from cosmic rays and stellar evolution to studies of gravitational waves and dark matter,” says astrophysicist David Smith of the Bordeaux Astrophysics Laboratory, part of the French National Center for Scientific Research (CNRS). ).

“This new catalog brings together comprehensive information on all known gamma-ray pulsars to advance new avenues of research.”

Pulsars are among the most extreme objects in the universe. They are a subcategory of neutron stars, which are the collapsed cores of massive stars that are not massive enough to collapse into a black hole. The difference between a normal neutron star and a pulsar is pulsation. Pulsars emit powerful jets of radiation from their poles like a searchlight piercing the cosmos.

Another thing pulsars do is usually spin incredibly fast. And we say crazy fast. Some of these stars, known as millisecond pulsars (MSP), can complete one revolution in 10 milliseconds. The fastest known pulsar actually spins 716 times per second. Here’s a series of pulsar pulses converted into sound to give you an idea of ​​what this means.

We know about 3400 pulsars. For most, radiation beams fall at radio wavelengths. However, a small number of pulsars can emit gamma rays, the strongest radiation known in the universe. Gamma pulsars accelerate particles to extremely high energies in their strong magnetic fields, resulting in powerful, invisible bursts of light.

About 10 percent of known pulsars are now gamma-ray emitters, according to the new catalogue. Although what we were able to detect is subject to some selection bias (limitations of our technology, for example), it is a large enough sample compared to the radio population to understand what makes a pulsar a gamma emitter.

There are other ways to use the new population. The timing of pulsars is often extremely precise, especially pulsars with millisecond-scale spin rates, 144 of which are catalogued. This means they could be used for important applications such as space navigation as the number of missions to the stars increases.

We can also use them to detect gravitational waves based on anomalies in the timing of the signals. This could represent the expansion and contraction of spacetime that occurs when a gravitational wave from a massive event passes through it. And we can use them to do relativity tests.