About 1,000 light-years from where you sit lies a spinning neutron star that is highly magnetized and dense enough to weigh as much as a tablespoon of Mount Everest. It’s a busy sight to say the least, so astronomers naturally love studying it. You may have even heard its name before: Vela Pulsar.

And on Thursday, October 5, scientists announced that data from the High Energy Stereoscopic System (HESS) observatory in Namibia shows that this cosmic wonder has gotten a little more surprising. Vela appears to emit the highest-energy radiation ever seen from a pulsar.

In particular, this object appears to emit gamma photons of at least 20 teraelectronvolts (TeV), or 20 trillion electronvolts, which are associated with the wavelengths that carry the most energy of all waves in the electromagnetic spectrum. (1 electron volt is equal to the amount of energy an electron receives after being accelerated by 1 volt of electricity.)

To put this into context, you would need about 2,000,000 typical photons from a solar flare to produce a 20 TeV photon, says Arash Giannati-Atai, research team leader and scientist at the Astroparticle and Cosmology Laboratory in France. “Approximately 2×10^13 visible photons are required compared to visible light,” Giannati-Atai told Space.com.

Although Vela is a fairly “normal” pulsar that spins 11 times per second, the researcher explains that it is an important object in astronomy because it is so close to us in space.

“Aiming with our telescopes was almost mandatory!”

As a general rule, pulsars are expected to emit radiation with energies below tens of gigaelectronvolts (GeV), let alone the extreme TeV region. (1 gigaelectronvolt equals 1 billion electronvolts). Even Vela initially showed some sort of limitation when it came to radiative emissions, according to the team; in fact, although some theoretical predictions suggested that Vela could emit emissions in the TeV range, no one suspected that the researchers had reached a very large 20. TeV. watch.

“We were looking for pulsed emission from Vela at lower energies,” Jannati-Atai said, “but finding photons as high as 20 TeV was a real surprise.” The only other pulsar observed so far with emission at the TeV level is the Crab pulsar, located 6,000 light-years from Earth, but even that has an emission of about 1 TeV. Finally, there is one more interesting discovery about Vela to discuss before moving on to some of the implications of this high-energy observation.

At the risk of oversimplification, the team found that Vela’s high-energy photons correspond to a previously unknown spectral component of pulsars. A pulsar’s “spectrum” is a diagram that represents all the different intensities of light and energy the object emits. (This doesn’t just apply to pulsars. Scientists can study many spectra of cosmic entities if light is present.)

So essentially in the Vela spectrum the team saw a rapidly growing pattern and a clear difference between TeV emissions and low-level emissions. This means that very energetic photons cannot be a continuation of lower energy photons, so the latter grow and grow until they reach the TeV state.

“This is different from the Crab pulsar,” in which the energy spectrum is a continuation of its emission in the GH, Giannati-Atai said.

What can we do with this information?

As for what this might mean for astronomy in general, first of all it tells us a lot about one of the most incredible objects in our universe.

“Pulsars are magnificent in a zoo of space objects,” Jannati-Atai said. “These are space laboratories with incredible capabilities that we cannot achieve anywhere on Earth.”

Even the history of the origin of pulsars is quite fascinating. These are the remnants of the swirling corpses of stars that once died in a supernova explosion; They consist almost entirely of neutrons and sometimes emit beams of radiation that scan our solar system. In fact, it is these scans that occur at regular intervals that allow scientists to compile the spectra of these objects.

As Jannati-AtaΪ touches on, this extreme is why scientists study the space around pulsars to test some fundamental physical concepts, calling them “space laboratories.” Most importantly, experts want to know whether Albert Einstein’s theory of general relativity applies to pulsars; because these objects are among the most gravitationally dense things in the universe, and general relativity is a groundbreaking explanation of gravity. For this purpose, as far as we know, it is.

Additionally, Giannati-Atai says these discoveries place tight constraints on our understanding of the source of pulsar radiation. Currently, scientists believe that the source is fast-moving electrons that form and accelerate in the pulsar’s magnetosphere, then move towards the object’s periphery. But this model doesn’t actually explain the team’s observations; For radiation up to 20 TeV something else must happen.

And while the researchers have some ideas, they aim to fully solve this puzzle with future observations. For now, we can enjoy that these results officially open a new path for scientists working among the stars. Source