A pulsar is a highly compact and incredibly dense astronomical object that emits beams of electromagnetic radiation, including radio waves, X-rays, and gamma rays, from its magnetic poles. Like a cosmic lighthouse, these universal oddities emit energy beams into space, and these beams appear to “pulse” or flash as the pulsar rotates.
While we’ve known about these rotating neutron stars for a
while, according to Nature, scientists recently discovered a pulsar that has
emitted the largest burst of gamma rays ever recorded, making it the most
powerful pulsar that we know of.
Pulsars, a type of neutron star, are immensely powerful, but
the latest discovery reached 20 tera-electronvolts, that’s 10 trillion times
more energetic than light.
Using the H.E.S.S. Observatory in Namibia, researchers
observed a pulsar named Vela, located nearly 1,000 light-years from Earth,
emitting bursts of gamma rays with energies reaching a staggering 20
tera-electronvolts. To put this into perspective, these emissions are
approximately 10 trillion times more energetic than visible light. The findings
reveal that these bursts are a staggering 200 times more energetic than any
beam previously documented.
The leader of the research team, Arache Djannati-Atai from
the Astroparticle & Cosmology Laboratory in France, claims that learning
about Vela has completely challenged all previous knowledge about pulsars and
forces scientists to rethink how these neutron stars work. He said, “The
traditional scheme according to which particles are accelerated along magnetic
field lines within or slightly outside the magnetosphere cannot sufficiently
explain our observations.”
Pulsars are a unique type of celestial body, essentially
neutron stars, formed when a massive star undergoes a supernova explosion but
doesn’t collapse entirely into a black hole. These incredibly dense objects
have highly active magnetospheres, where electrons are accelerated and then
ejected in beams from the star’s poles. As the star rotates, these beams sweep
across the universe, creating flashes of radiation that resemble the regular
intervals of a lighthouse.
Emma de Oña Wilhelmi, a co-author of the study and scientist
at H.E.S.S., emphasized the mind-boggling density of pulsars, using the
comparison that a single teaspoon of a pulsar’s material has a “mass of more
than five billion tonnes, or about 900 times the mass of the Great Pyramid of
Giza.”
Pulsars are a unique type of celestial body, essentially
neutron stars, formed when a massive star undergoes a supernova explosion but
doesn’t collapse entirely into a black hole.
The recent discovery is just a drop in the bucket of what
scientists have recently been learning about space (which in turn is just a
drop in the ocean when it comes to the infinite mysteries of the universe), but
this new discovery adds to the growing body of knowledge we have about pulsars.
In August, researchers studying another pulsar, PSR J1023+0038, located 4,500
light-years from Earth, unraveled its peculiar behavior. This pulsar was found
to alternate between two modes: one in which it emits high-frequency visible
light, ultraviolet light, and X-rays, and another in which it dims and emits
lower-frequency radio waves.
The scientists theorized that during the lower-frequency
mode, matter falls toward the pulsar’s surface and is subsequently pushed back
out through its jet. This process heats up the surrounding matter, triggering
the higher-frequency mode.
A single teaspoon of the material within a pulsar is
thousands of times denser than the Giza Pyramids.
Gamma-ray observations have previously demonstrated that
isolated pulsars are exceptional particle accelerators and sources of
antimatter. However, many questions remained unanswered regarding the
acceleration and radiation processes involved, as well as the locations where
they occur. Most gamma-ray pulsars observed so far exhibited strong cutoffs or
breaks in their radiation spectra above energies of a few gigaelectronvolts.
However, the latest findings from the High Energy
Stereoscopic System’s Cherenkov telescopes reveal a radiation component from
the Vela pulsar that extends beyond this cutoff, reaching energies of at least
20 teraelectronvolts. This magnitude is an order of magnitude greater than the
Crab pulsar, the only other pulsar previously detected with a similar energy
range. These results challenge previous pulsar knowledge and open up avenues
for studying other pulsars emitting Mult teraelectronvolt radiation, providing
further insights into the extreme energy processes at play.