Sun

In a pot on the stove, water starts to churn from the bottom long before the whole thing boils. Bubbles of steam rise from the base even though the burner itself hasn't heated up yet.

The Sun has a layer called the chromosphere, sitting just above the visible surface. Bright arcs often flare up there, visible through telescopes, but to understand what ignites them, you need to look at invisible magnetic fields.

A laser beam strikes a thin target hidden inside layers of another material. Within billionths of a second, the material is compressed to a density of 25 grams per cubic centimeter, as if a piece of lead became more than twice as heavy without moving an inch.

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 Sun has quiet regions where the magnetic field is barely visible. But even there, sound waves find loopholes to rise higher. These loopholes are magnetic tubes that expand upward like funnels. Inside them, sound travels more freely.

Two spinning tops whirl so close they nearly touch. One is scorching blue, the other dim white. Together they complete a full orbit in twenty hours. This is the pair Feige 64: a blue star with a mass of just a third of the Sun's, and a white dwarf, the cooled core of a former star, one and a half times heavier than our Sun. The blue star seems too hot for its mass.

In a pot of boiling soup, light fat droplets rise to the top, while heavy vegetable chunks sink to the bottom. Particles in the tenuous hot gas around the Sun and other stars behave much the same way — except instead of broth, there's a mixture of charged particles: electrons, protons, and alpha particles.

In the kitchen, when a pan heats up, your hand feels the heat before you even touch it. A solar telescope picks up similar invisible heat — only from a star, not a stove. The instrument, called HATS, captures radiation in the terahertz range, which was previously little studied due to technical difficulties.

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.

The solar wind is a continuous stream of charged particles flowing from the Sun. It has two main components: protons (hydrogen nuclei) and alpha particles (helium nuclei, four times heavier).

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.

The solar corona is the Sun's outer atmosphere, heated to millions of degrees. How it gets so hot is still unclear. One candidate is torsional waves: they twist magnetic field lines like a rubber band. Such waves were recently spotted with the new Daniel K. Inouye Solar Telescope.

A distant light in the fog looks tiny and reddish: you'd think it's miles away. But then the light shifts sideways, and it becomes clear: it's a cyclist twenty steps away, just with a nearly dead rear light. That's how, in 2025, astronomers stumbled upon 'Capotauro'—a compact red source in images from the James Webb Space Telescope.

A sunspot, a dark island on the fiery surface, lives its own turbulent life. Beneath it, in invisible depths, giant magnetic loops drift like twisted cables. When such a loop emerges, it can discharge as a flare, and hurl clouds of charged particles into space. Scientists have long tried to understand what determines the strength and suddenness of these events.

A sunspot, a dark island on the fiery surface, lives its own turbulent life. Beneath it, in invisible depths, giant magnetic loops drift like twisted cables. When such a loop emerges, it can discharge as a flare, and hurl clouds of charged particles into space. Scientists have long tried to understand what determines the strength and suddenness of these events.

The solar corona lives its own turbulent life. Magnetic fields here are governed by the motions of the dense surface — the Sun's photosphere — but occasionally they rewrite the magnetic pattern themselves.

The solar corona lives its own turbulent life. Magnetic fields here are governed by the motions of the dense surface — the Sun's photosphere — but occasionally they rewrite the magnetic pattern themselves.

Each morning, dozens of telescopes swing toward the Sun. Their cameras catch a narrow band of red light — the Hα line, discovered by Johann Balmer. The images reveal dark, whimsically curved threads. They look like stitches in a giant tapestry sewn through the blazing corona.

Solar neutrinos are tiny particles born in the Sun's core by the trillions every second. They pass through Earth almost without noticing it, and for a long time they were considered absolutely stable. But perhaps they too can "age"—decaying imperceptibly, vanishing on their way to us.

The Sun is a giant cauldron where light struggles through a thick layer of scorching matter. On its way out, photons (light particles) constantly bump into atoms and lose energy. How strongly matter holds back light is called "opacity," and it determines how quickly heat escapes. Iron is one of the main culprits for opacity in the Sun's interior.

27 days at the equator, 32 at the poles. Five days' difference, and over a year, the equator gains almost a week. A gas ball 1,4 million kilometers in diameter spins like a layered top: each layer moves at its own speed.

27 days at the equator, 32 at the poles. Five days' difference, and over a year, the equator gains almost a week. A gas ball 1,4 million kilometers in diameter spins like a layered top: each layer moves at its own speed.

The Sun is constantly struck by blows — magnetic reconnection in the plasma releases energy, making the corona flare up. After each such blow, magnetohydrodynamic waves linger in the plasma loops, like the fading ring of a bell.

The Sun continuously scribbles magnetic fields across its surface. These patterns are not mere ripples but a handwriting in which nature has encoded warnings of flares. A flare is an explosion that releases the energy of billions of nuclear bombs in minutes, ejecting streams of plasma and radiation into space.

Deep in the Amazon rainforest, beneath a multi-layered canopy of leaves, lie vast earthen figures — squares, rectangles, the occasional rhombus. For decades they teased archaeologists with their silent geometry, until a researcher armed with orbital optics saw them as an astronomical instrument.

A living power system is like an organism: power lines are vessels, current is blood. Data, however, are nerve impulses that used to be lost. mAIEnergy connects these 'nerves' to a shared 'brain'. This data repository combines satellite images, electricity meter readings, articles, and weather reports.

A waterfall that doesn't heat up from the fall but freezes — that's roughly how gas behaves as it flows onto a neutron star in an X-ray pulsar when the star shines dimly. Usually, infalling matter is heated to a white-hot glow, but new work shows the opposite.

A cosmic detective story spanning a decade and a half has turned up an unexpected clue. The Fermi telescope, which scans the sky in gamma rays, has detected a steady, faint glow enveloping the entire Milky Way. It looks nothing like the light from stars or hot gas — more like a dim, all-pervasive haze.

The cosmological debate is like two craftsmen measuring the same wall but getting different lengths. One uses a tape measure, applying it to nearby landmarks — Cepheids (pulsating beacon stars) and Type Ia supernovae (flashes of dying stars). He finds the wall is stretching at 73.5 arbitrary units.

For years, the Sun teased astrophysicists. In its atmosphere, refractory elements, like spices in a basic recipe, were slightly less abundant than in nearly identical twin stars. Suspicion arose: could our star be modest, skipping the planetary "dessert" that others devour with gusto?

For years, the Sun teased astrophysicists. In its atmosphere, refractory elements, like spices in a basic recipe, were slightly less abundant than in nearly identical twin stars. Suspicion arose: could our star be modest, skipping the planetary "dessert" that others devour with gusto?

The Sun is not just a blazing ball, but a colossal orchestra, where the strings are solar filaments — giant arches of dense plasma floating in the scorching corona. They tremble, and each oscillation is an encrypted melody of magnetic fields.

The Sun is not just a source of heat; it's also the largest lens in the solar system. Its gravity bends light rays like glass, focusing them into a bright ring far beyond Pluto's orbit. If light from a distant planet enters this ring, astronomers could reconstruct its portrait — not a point, but a map with surface details.

Solar flares are powerful explosions on the Sun that can knock out satellites and blackout cities. Predicting them is complicated by the tangled magnetic fields in sunspots.

Engineers create an alloy for solar concentrators by adding hard particles — like raisins in dough, to help it hold its shape under extreme heat. Too big a raisin and the material cracks. Previously, scientists manually counted these particles on microscope images.

In 5 billion years, the Sun, having exhausted its fuel, will start to swell, turning into a red giant. Like a balloon losing air, the star will weaken its gravitational grip, and Earth — a grain of sand on an invisible thread — will drift to a more distant orbit.

A planet glides across a star's disk, and for a moment becomes a flashlight. It blocks a tiny patch of surface, revealing details that otherwise escape our view. That's exactly how astronomers peered into the dark spots on V1298 Tauri, a young twin of our Sun. They were aided by the James Webb Space Telescope JWST and three giant planets in orbit.

The Sun is a giant nuclear reactor that continuously sends us light and heat. But it also has another, almost silent postal service: every second, tens of billions of neutrinos, ghostly particles born in the thermonuclear furnace, fly through a square centimeter of your palm. Most of them leave no trace.

Moments before totality, swift shadow bands glide across the ground, like ripples from pebbles tossed into water. For centuries, this phenomenon baffled scientists. It turns out the key is that light is a wave. The Sun isn't a pinpoint lamp but a vast disk. When the Moon nearly covers it, a thin glowing crescent remains.

The Sun is not just a source of light but a giant laboratory where ghostly particles are born. Every second, billions of neutrinos fly through your body, barely noticing you. But inside the Sun, these particles behave differently: they change their type on the fly, like an actor playing three roles in a single play.