The Fastest Dead Star: A Neutron Star Spinning at 716 Times Per Second

The astronomers have recently discovered a neutron star, or what one might call a "dead star," oscillating enormously fast, managing up to 716 revolutions every second. This makes it one of the most rapid spinning stars ever discovered anywhere in the universe.

And it's not about only speed—this neutron star is externally erupting almost continuously with very powerful explosions. But before digging deeper into the enigmas this neutron star holds for the human race, let's first understand what exactly these stars are.

They form from remnants of the really massive stars, at least eight times the mass of the Sun, such that when these stars consume their nuclear energy or fuel, they no longer support against the attractive inward pull of gravity on all their own material. Thus, their cores collapse, causing a tremendous supernova explosion that blasts away the outer layers.

What remains is an ultra-dense core: that's a neutron star. These stellar remnants are incredibly small, usually just about 12 miles wide, all the while packing in more mass than the Sun.

Neutron stars are, on top of it, downright horrible; they are also big. Imagine taking the weight of a couple of Suns and condensing it to the size of a city. A single teaspoon of neutron star material is likely to weigh about 10 million tons-that is, as much as 85,000 blue whales combined. Such incredible densities give rise to the tremendous gravitational fields neutron stars possess.

Matter falling onto the neutron star accelerates to millions of miles in a few hours and then slams into the surface. The energy released from such an impact is incredibly tremendous.

Now, despite its name, inside a neutron star there are not only neutrons-a few protons survive down there too. Normally, protons repel each other since they have the same positive charge. But in a neutron star, that implosive gravity compresses them close until the strong nuclear force takes over. It pulls them toward the neutrons like they're all part of the same team.

Things get stranger inside the star the deeper you go. At almost the surface, chunks of neutrons collect in blobs kind of like neutron gnocchi. Below that, these blobs form a long spaghetti layer, linking together. I'm getting hungry.

Under even more pressure, the spaghetti chains became positioned beside one another, forming flat sheets-consider it to be neutron lasagna. Go any deeper, and eventually lasagna falls apart into a uniform goo. But then there's nothing smooth about it; there will be holes-long, tube-shaped voids that look a lot like penne pasta.

So, inside a neutron star, you've got layers of gnocchi, spaghetti, lasagna, and penne pasta. And each of them represents the mind-bending results of physics under insane pressure. Okay, I'm definitely having Italian for lunch today.

Recently, the neutron star was discovered in a binary system inside a dense star cluster. Located close to the center of the Milky Way galaxy, this stellar cluster is roughly 26,000 light-years away from Earth in the direction of the Sagittarius constellation.

The spin of the star is a record in itself. If we consider not a second but a minute, it'll be in excess of 42,000 rpm. Simultaneously, the newcomer also spins in tandem with another neutron star at the same speed. Such extreme rotation rates are rarely seen and thus make these stars cosmic behavior-outliers.

Oh wait—we can't not mention the binary partner of our neutron star. It's a white dwarf, a very dense star remnant about the same size as our Sun. This white dwarf isn't all that slow either; it completes an orbit around the neutron star every 11 minutes.

This marks the couple as the shortest orbital period so far. Picture a stellar body circling its companion faster than you can whip up a cup of coffee. That really puts the speed in perspective here. While the rapid orbit shows how ridiculous gravity is in action in this cosmic system.

So you might be wondering-what is the reason for the fast spin of neutron stars? It is called conservation of angular momentum.

Let me explain this. When a massive star is collapsed into a neutron star, there is an enormous amount of shrinkage in size. This rapid process gives a boost to the spin, and fast is the very term to describe the shrinking. Just like ice skaters pull their arms in to spin faster, so the decreasing size adds to increasing spin. When pulled in, much angular momentum accumulates to give a neutron star some crazy fast equatorial speeds.

The secret to an even faster spin in such binary systems is the ability of neutron stars to steal mass off their companions. Simply refer to this as theft? Well, actually, it is accretion. As accreted mass gets plundered, it plunders the very angular momentum that gives the spin to the neutron star.

Accreting material accumulates on the surface of the neutron star. In the end, it sets off huge thermonuclear explosions detectable for many, many kilometers, which can briefly cause the neutron star to shine up to 100,000 times brighter than the sun. This helps astronomers study the many details of these extreme surroundings.

NASA's x-ray instrument onboard the International Space Station, officially called the Neutron Star Interior Composition Explorer (thankfully nicknamed NICER), observed 15 thermonuclear explosions on the surface of our neutron star between 2017 and 2021.

One out of those bursts had special properties called thermonuclear burst oscillations. These are patches of brightness on the burning surface layers of accreting neutron stars that are highly asymmetric. This pattern matched the spin rate of the neutron star and thus confirmed its extreme rotational speed.

But wait-the best is yet to come.

While neutron stars are one kind of extreme, there exists another subclass of them called magnetars, that takes the extreme to another level!

Magnetars are neutron stars that have exceptionally strong magnetic fields—up to even one thousand trillion times greater than that of Earth's—and this differentiates them from other neutron stars. The strong fields create distortions in nearby molecules that make it impossible for life to exist anywhere close to them. The energy density of a magnetar's magnetic field is 10,000 times that of the mass density of lead. Magnetars also emit extraordinarily high bursts of X-rays and gamma radiation capable of momentarily outshining entire galaxies. These bursts are often associated with starquakes, violent movements within the crust of the magnetar brought about by the magnetic forces it generates. For instance, in 2004, a particular gamma-ray burst from a magnetar was so powerful that it disturbed the Earth ionosphere. It made it to Earth, and it had even managed to be so powerful that a number of satellites recorded it. The image of the Swift satellite, which was specially designed to detect gamma-ray bursts from across the universe, didn't catch the explosion. It was bombarded with so much power that the sensors got completely overloaded. In general, however, Swift had not even been pointed at the burst. The strong energy passed through the spacecraft by such a degree as to still overwhelm the cameras. Imagine what would happen if just one magnetar were situated as close to Earth as the Moon: the magnetic field would erase all the data from credit cards present on the planet by wiping the magnetic stripes clean. Wow—that's the level of power we're talking about. Magnetars are bursting with activity, but for a relatively short while. After roughly 10,000 years, the intense magnetic fields decay. After that, they cease to emit high-intensity X-rays and gamma rays. Astronomers expect at least another 30 million magnetars in the Milky Way's stillness. These silent cosmic relics are dispersed throughout the galaxy. Neutron stars and magnetars function for physics laboratories, allowing astronomers to see how certain matter behaves under circumstances that cannot be re-created on Earth. The tremendous density of these objects provides insight into what occurs during the compression of protons and electrons into neutrons. It creates forms of matter that are absent from anywhere else in the universe. These violent explosions on neutron stars and magnetars are also responsible for the creation of most of the very heavy elements like gold and platinum, which then stay afloat in space as cloud material is blown apart, later falling into planets, stars, and—you and me. Oh, yeah—NASA's instrument NICER has been one of the main pieces figuring out neutron stars. Its ability to detect X-rays with high precision has let astronomers study the rapid spin of the neutron star we're talking about and the thermonuclear bursts on its surface. So, if it's not NICER than that, what could be considered NICER?