pulsar wind

A swing that rocks on a sawtooth hill behaves strangely: without kicks, it gets stuck in the first dip, but with rhythmic pushes it can move uphill, downhill, or stay frozen in place. That is exactly what physicists saw when they placed a single dust grain in a trap with a sawtooth bottom and started pushing it alternately with laser beams.

Two caravans travel toward each other along a narrow road. One is wide and slow, carrying a load of density. The other, a string of light carts carrying current, slips between the first. Thus, in a magnetron discharge, two structures rotating in opposite directions coexist: the density spoke and the current filaments.

A laser pulse slams into a gas cloud and knocks electrons out of it, leaving behind a bubble: a cavity almost devoid of particles. This bubble races through the plasma at nearly the speed of light, and its walls drag along the electrons trapped inside, much like a speedboat tows a water skier.

In 1054, a star flared up in the constellation Taurus. The light of its death was so bright that it was visible in daylight for nearly a month, and Chinese astronomers recorded it in their chronicles. Today, the Crab Nebula is spreading over that spot, and its claws are clouds of gas still being whipped up by the dead star at its center.

Inside a solar flare, magnetic field lines snap like stretched rubber bands and reconnect — releasing in minutes enough energy to power humanity for millions of years. In the lab, this process, magnetic reconnection, could long be triggered but not stopped. Now physicists have a switch.

The solar wind is a stream of charged particles constantly blown off the Sun's surface, filling the entire solar system. It's not like a steady breeze: it has eddies, gusts, and calm patches. Scientists call this turbulence.

Pulsar PSR J1740+1000 is a city-sized star spinning faster than a kitchen blender. After a supernova explosion, it left behind a dense core that accelerates particles to near-light speeds. These particles fly into space, and previously it was thought they scatter in all directions, like splashes from a stone thrown into water.

In the first seconds after the Big Bang, the Universe left us not only light but also something far more elusive — the relic neutrino background. This echo of creation permeates every cubic centimeter, yet we barely notice it.

In 2017, the Antarctic neutrino telescope IceCube detected a particle with an energy of about 290 TeV arriving from deep space.

In the constellation Aquila, about 40,000 light-years away, one of the most powerful natural accelerators in the Galaxy is at work. It's the microquasar GRS 1915+105—a pair consisting of an ordinary star and a black hole.

At the heart of a warp drive lies Einstein's idea that massive bodies curve spacetime — the very stage on which all cosmic events unfold. Picture a bubble of such curved spacetime. Inside it, the ship floats without any G-forces, like a passenger in an airplane cabin who doesn't feel the headwind.

Blacksmith's bellows fan the fire by forcefully pushing out air. In space, the shock wave from a supernova, a concept introduced by Fritz Zwicky, acts like such bellows: it catches up with a giant bubble of charged particles and magnetic fields formed around a spinning neutron star…

At the heart of the Galaxy, about 7 kiloparsecs away, lies a true natural particle accelerator. This is a rapidly spinning neutron star — the pulsar PSR J1849-0001, left behind by a supernova explosion.

The paradox of the young solar wind has long puzzled heliophysicists. Measurements showed that near the Sun, proton beams aren’t smeared out but sharply compressed, as if someone had neatly hammered them into the shape of a hammerhead.

Space is full of invisible sprinters — particles racing nearly at the speed of light. They are caught in the solar wind, near neutron stars, and even in the intergalactic void between galaxies. But what accelerates them where there are no shock waves or magnetic reconnections?

Imagine a three-faced dancer on the crest of a light wave. One face is a catcher, absorbing incoming photons. The second is a perfect mirror, throwing light back. The third is frosted glass, scattering rays in all directions. As long as speed is low, the dance is harmonious. But at near-light speeds, the choreography breaks. This is like a surfer chasing a wave.

In an orchestra, each musician plays their own part, but at a certain moment all instruments pause on a single note. Cosmic rays behave somewhat like this — particles flying toward us from distant stars.

A crowd is trapped in a narrow corridor between two rows of mirrors. Every now and then, someone shoves the wall hard, and a rumble rolls down the corridor — similarly, in the plasma of galaxy clusters, whistler waves and ion-cyclotron waves appear.

A massive star collapses, and a black hole is born, surrounded by a disk of incandescent plasma. For narrow jets to burst out of this disk, an ordered magnetic field is needed. But inside the star, it's tangled.

A thin layer of oil on the surface of water breaks into separate droplets at the slightest disturbance. Something similar happens in the pulsar wind — a stream of particles ejected by a rapidly rotating neutron star. This stream also contains plasma layers, which can break apart into clumps — magnetic islands.

When a massive star explodes as a supernova, its outer layers are blasted into space at thousands of kilometers per second. A shock wave forms — a giant invisible bulldozer that sweeps up interstellar gas and dust. In this maelstrom, particles can be accelerated to energies comparable to that of a flying tennis ball compressed into a single proton.

When water boils in a kettle, waves of steam ripple through the kitchen. A similar process happens in space, in plasma — gas so hot that electrons are stripped from atoms. Around black holes and neutron stars, this plasma isn't just hot: its particles zip around at nearly the speed of light.

A pulsar is a dead star spinning at breakneck speed, sending out radio pulses like a lighthouse. But for PSR J1928+1815, the signal sometimes cuts out for 3.6 hours. Something is blocking the beacon. A companion star orbits the pulsar, and its shadow falls on us.

The black hole MAXI J1810-222 behaves like a giant vacuum cleaner with a reverse valve: it pulls in matter, but some of it gets spat back out into space. This "backflow"—a stellar wind — had been spotted by astronomers before, but only as a blurry smudge in X-rays.

Deep in the constellation Aquila lies a nebula that looks like an expanding bubble. It is inflated by a tiny star the size of a city — a pulsar that makes several rotations per second and loses rotational energy. Usually, such bubbles shine exactly as brightly as their pulsar is powerful.

A giant cosmic funnel sucks in gas from its surroundings. But not all of that gas falls in — some is spat back out, like splashes from boiling water. That's exactly what the ultraluminous X-ray source NGC 5204 X-1 does: a compact object (likely a black hole) feeds so voraciously that the excess escapes in powerful jets.

The X-ray pulsar Centaurus X-3 is a neutron star that spins rapidly and emits pulses of X-ray light like a lighthouse. Scientists pointed three space telescopes at it and studied the polarization of its emission — how the electric field of the light wave oscillates.

Hot plasma in a tokamak is like a temperamental beast: you need to hold it in, but not let it overheat. In the ASDEX Upgrade reactor, researchers found a regime where plasma eddies solve this problem on their own. Stochastic modeling showed that oscillations at the plasma edge fling out blobs, like bubbles from a boiling pot.

The VLA radio telescope peered into the Boomerang Nebula — a cloud inflated by the wind from a rapidly spinning neutron star. The new images reveal details as small as a lunar disk on the sky: an elongated core around the pulsar and a long arc curving around it from the north.

A laser beam usually travels straight, like a jet of water from a hose. But what if you twist that jet like the thread of a corkscrew? You get a light spring — a beam that, as it moves, also spins around its own axis. At every point in space, its brightness traces a spiral, and if you place a flat screen in its path, you'll see a rotating spot of light.

The Sun constantly emits a stream of charged particles — the solar wind. Among them are many electrons, some of which fly back toward the Sun. But observations show that fewer electrons return than expected.

In December 2024, quasar PG 1211+143 found itself in the crosshairs of two X-ray observatories at once: the spectrometers on XRISM and XMM-Newton observed it simultaneously. A quasar is the extremely bright core of a distant galaxy, where a supermassive black hole is accreting surrounding gas.

A radio telescope picks up a signal from the Crab Nebula, and instead of a smooth line, the screen shows bright and dark bands, like on a zebra's hide. This is the emission from the pulsar, a rapidly spinning neutron star left over from a supernova explosion.

Two galaxies collided, and from their center an invisible fountain erupts. The ALMA and VLT telescopes peered into the heart of the IRAS20100-4156 system — where two stellar islands are merging. There, work is in full swing: hundreds of new suns are being born, and their heat drives a stream of cold gas outward. This stream is like a giant's exhale.

In the binary system 4U 1624-49, a neutron star pulls gas from its companion star. This gas spirals into a glowing disk, like water in a funnel. And from the edge of this funnel, a hot stream tears away — hydrogen and other elements fly off at speeds up to 320 kilometers per second.

The Sun constantly emits a stream of charged particles, mostly hydrogen — the solar wind. Sometimes the Sun ejects dense blobs of magnetized gas, inside which calm usually reigns. But in 2000, scientists noticed two regions inside one such cloud where the gas was churning.

The pulsar in the Crab Nebula blinks like a lighthouse: every 33 milliseconds it sends out a radio pulse, and it does so with the precision of atomic clocks. But sometimes its rotation stumbles: the star suddenly speeds up slightly, as if something inside it is shifting.

In a hot gas of charged particles — plasma — chaotic electric fields work like a sieve. A slow particle gets surrounded by a cloud of opposite charges, which cancels the external field. A fast one sheds this armor and gets accelerated.

A wind blowing against the planet's rotation stokes a carbon forge. That is what the atmosphere of PSR J2322-2650b looks like: a Jupiter-like companion to a millisecond pulsar.