dwarf galaxy

A filament of the cosmic web stretches through the young universe, and strung along it like beads on a necklace are galaxies. In the core of the SSA22 protocluster, which in a few billion years will become the center of a massive cluster, these beads are still hot and dusty: stars are being born inside them, and cold gas serves as fuel.

In the stellar family of the Phoenix galaxy, there are five old globular clusters, and the sixth child was long considered a foundling. The object Fornax 6, located just 270 parsecs from the galaxy's center, looked like a random clump of field stars or a compact group of distant galaxies. Astronomers argued over whether it deserved to be called a cluster.

In a quiet back alley of a galaxy, where stars are rare and old, a light suddenly flares up, brighter than an entire galaxy. This is a Type Ia supernova: a thermonuclear explosion of a white dwarf that astronomers use as a standard candle to measure cosmic distances.

At the center of an ultra-compact dwarf galaxy, a very dense stellar system spanning tens of light-years, there is a vacuum cleaner at work. But instead of dust, it sucks in gas shed by dying stars. This gas does not fly off in all directions; instead, it spirals into a funnel, a rotating disk that gradually settles onto the black hole.

In a distant galaxy, light from hot gas should reveal its composition. The James Webb Telescope split that light into a spectrum, and astronomers saw: oxygen lines too weak.

In a distant galaxy, light from hot gas should reveal its composition. The James Webb Telescope split that light into a spectrum, and astronomers saw: oxygen lines too weak.

The night sky only looks black: telescopes reveal millions of galaxies, but some are so dim they blend into the background. Astronomers caught just such a "nearly invisible" one by chance while observing the Virgo Cluster with the two-meter telescope at Teide Observatory. The galaxy is named TTT J1237327+143535.

The night sky only looks black: telescopes reveal millions of galaxies, but some are so dim they blend into the background. Astronomers caught just such a "nearly invisible" one by chance while observing the Virgo Cluster with the two-meter telescope at Teide Observatory. The galaxy is named TTT J1237327+143535.

Faint galaxies scattered across the Perseus cluster are like ghosts among their bright neighbors. They are so diffuse that distant objects shine through them, and they contain hundreds of times fewer stars than our Milky Way.

Faint galaxies scattered across the Perseus cluster are like ghosts among their bright neighbors. They are so diffuse that distant objects shine through them, and they contain hundreds of times fewer stars than our Milky Way.

The night sky seems unchanging, but galaxies constantly exchange matter. The Milky Way, like a great river, absorbs smaller streams — dwarf galaxies. Along with their stars, planets may also come to us.

In the first moments after the Big Bang, matter and antimatter should have been created in equal amounts. But today, everything around us is ordinary matter, and antimatter is almost nowhere to be found. Where did it all go? The standard answer: a tiny imbalance in favor of matter wiped out almost all antimatter.

In the dark kitchen of the Taurus molecular cloud, 450 light-years away, dozens of planetary systems are being prepared. Each young star is a chef, and its protoplanetary disk is a counter piled with flour-like dust and steam-like gas.

Think of a merry-go-round: the farther you sit from the center, the faster you're carried around. For a long time, astronomers assumed galaxies work the same way — stars at the edges should orbit more slowly than those near the center. But back in the 1970s, it turned out that in many spiral galaxies, the speed of stars barely drops with distance from the center.

A dance floor where couples whirl. At the center, an invisible master of ceremonies sets the rhythm. This is the supermassive black hole at the heart of the Milky Way, and the couples are stars whose orbits astronomers have tracked for years. But what if the master himself is wrapped in a fluffy fur coat of tenuous matter?

The night sky looks like a random scattering of stars. But zoom out to enormous distances, and the chaos disappears. Galaxies gather into long filaments and flat walls, with colossal voids gaping between them — cosmic voids. This structure is called the cosmic web.

The night sky is like an ocean: the longer you stare, the more faint lights you notice in the depths. That's how astronomers, peering into the outskirts of the Milky Way, found Aquarius IV — a tiny stellar system that had been hiding in the dark until now. The system was spotted in images from an early survey by the future Vera Rubin Observatory.

A globular cluster, a dense swarm of hundreds of thousands of stars, plows through a galaxy like a bullet through water. In ordinary dark matter (the invisible mass that holds galaxies together), it should quickly lose speed due to dynamical friction.

A star wrapped in an invisible blanket warms up more than it should. That's exactly how ten red dwarfs look, which astronomers from the Hephaistos project have been monitoring. These stars lie within 300 parsecs (about 1000 light-years) of us and emit far more infrared energy than their modest sizes can explain.

A star's radius drops by a thousand kilometers. Not because its mass increased, but because its own magnetic field squeezed the crust like an invisible corset.

10¹⁵ Gauss — that's the magnetic field found on some white dwarfs. It is billions of times stronger than what a compass shows on Earth. A white dwarf is not a star in the usual sense, but a cooled core the size of a planet. Inside, gravity opposes the pressure of degenerate electrons.

Two hundred and eighty-nine days: that's how long one rotation of the white dwarf white dwarf WD 1532+129 takes. This is not just a record: on its surface, near the magnetic poles, scars of iron and other metals appear — silent testimony to planets it has devoured.

The JWST spectrograph caught a barely perceptible dip in the spectrum of a distant galaxy — two lines, like shadows cast by cold gas. These are the sodium lines, the very yellow light of streetlamps. Here, at the edge of the visible Universe, they betray the slow exhalation of a galaxy returning matter to space.

It takes the stellar pair J05+50 nearly two months to complete one orbit around their common center. From Earth, it appears as a faint point in the constellation Hercules — 4625 parsecs away. Photometry of the binary star only captures a steady flicker of brightness, like the pulse of a giant heart.

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.

In the Galactic bulge, where the light of billions of stars merges into a continuous glow, four cold giants passed unnoticed. You can't see them through a telescope — too far, too dim.

Dwarf galaxies orbiting the Milky Way look as if they’ve survived a gravitational storm. Their stellar bodies are stretched, scattered by tidal tails, and heated from within.

In the young Universe, about ten billion years ago, galaxies resembled endless fields after a thunderstorm: everywhere, giant — thousands of light-years across — clumps of star formation were boiling up, where young stars were born with unbridled energy. Today, these patches are an almost vanished species: in nearby galaxies, raucous hotbeds are rare.

Within a field of view the size of a grain of sand held up to the eye, hundreds of galaxies lie hidden, smeared into arcs by the massive cluster Abell S1063.

Within a field of view the size of a grain of sand held up to the eye, hundreds of galaxies lie hidden, smeared into arcs by the massive cluster Abell S1063.

At the center of a tiny galaxy lies a dense clump of stars and dark matter. This clump, called a soliton, is not frozen in place: it quivers and oscillates like jelly on a plate.

The James Webb Space Telescope has peered into a strange binary world. Here, a dead star, a white dwarf, slowly roasts its companion, a brown dwarf. The object, named ZTFJ0038+2030, completes a full orbit in just a few hours. One side of the brown dwarf always faces the white dwarf, much like the Moon faces Earth.

Imagine a forest planted in a single day. At first glance, all trees look alike, but their cross sections tell different stories: some grew on clean soil, others on the ashes of ancient fires.

The Drake Equation is an attempt to guess the number of intelligent civilizations in our Galaxy. It’s like counting finished cakes in an unknown bakery: you know the ovens (stars), the baking sheets (planets), and the baking time. But were eggs added to the batter? Western science, relying on a single earthly recipe, considers them a rare ingredient.

The early Universe is often imagined as a nursery: most galaxies there are amorphous blobs, rowdy and irregular, choking on gas and bursts of star formation.

Lenticular galaxies are the cosmic quiet types: they have a disk but no bright spiral arms. For a long time, their origin remained a mystery. A team of scientists ran the Hydrangea computer simulation and traced the fate of each galaxy from its youth to the present day. On the mass–size diagram, these galaxies line up in a V shape.

The search for extraterrestrial intelligence is like panning for gold in an endless river. For decades, SETI has been listening to the hum of the Galaxy, but the ether is silent. It’s not about antenna sensitivity — it’s that we don’t know where to dip our pan.

Galaxies without dark matter are like beads from which the invisible thread has been ripped. Stretching around the elliptical NGC 1052 is a chain of eight ghostly dim dwarfs: they contain almost none of the mysterious mass that makes spiral arms rotate. Vera Rubin first showed that without the invisible framework, stars would fly apart.

Galaxies without dark matter are like beads from which the invisible thread has been ripped. Stretching around the elliptical NGC 1052 is a chain of eight ghostly dim dwarfs: they contain almost none of the mysterious mass that makes spiral arms rotate. Vera Rubin first showed that without the invisible framework, stars would fly apart.

Among the precious scatterings of the early Universe captured by James Webb, there are objects that resemble ruby beads scattered on black velvet. These are the 'little red dots' (LRDs) — compact sources with steep red spectra, inside which lurk supermassive black holes up to a hundred million solar masses.