galactic outflow

In a village smithy, the blacksmith pumps the bellows, and sparks fly into the darkness. So too in the galaxy AEON-z5, an active nucleus, like a red-hot forge, hurls metal-enriched material far beyond the stellar disk. The James Webb Space Telescope caught this process just a billion years after the Big Bang, when the universe was still in its infancy.

A harbor lives by the tide schedule. Water rises and falls, and with it everything changes: the level at the dock, the composition of the sediment on the bottom, even the salinity in the far corners. A galaxy works similarly, except instead of water it has gas, and instead of the Moon, it has its own stars and neighboring clouds.

A census by body shape: that's one way to describe what astronomers did with 6348 massive galaxies. Instead of height and weight, they measured how concentrated the light is toward the center, how flattened the galaxy is, and how asymmetric its shape is. Then they ran the same measurements on galaxies from three computer models of the universe and compared the results.

The night sky looks serene, but it is actually pierced by an invisible rain of charged particles: cosmic rays. Scientists have long tried to figure out where the most energetic ones are born. Until recently, it was thought that our Galaxy supplies particles up to about 4 EeV, the so-called "ankle" in the spectrum.

The night sky in neutrino light resembles a canvas worked on by two hands. One holds a broad, soft brush: these are supernova remnants, the shells left behind after stellar explosions. The other grips a fine, hard pen — microquasars, binary systems where a black hole twists matter into narrow jets.

An avalanche in a sandpile starts with a single grain. No one knows exactly where it will slip or how big the slide will be. But if you keep pouring sand, the pile itself reaches a state where avalanches of all sizes, from tiny trickles to massive collapses, follow the same law.

In the first half-billion years after the Big Bang, galaxies grew like crazy. Gas fell in rapidly and collapsed into stars without any resistance. This period is called 'unimpeded star formation.' It's like frying pancakes on a scorching skillet without a lid: splatters fly, but nothing holds them back.

In the heart of the Perseus galaxy cluster lives the galaxy NGC 1275. From its core blows a wind of superheated gas — astronomers have now seen it in detail for the first time. The wind shows up in the glow of hydrogen and oxygen. It accelerates to 570 kilometers per second — faster than a bullet.

Deep beneath the ice of the South Pole, nearly two and a half kilometers down, an unusual telescope is at work. It is not pointed at the sky but through the Earth. Its quarry: neutrinos, nearly elusive particles that pass through planets and stars without interacting with anything.

In 1,433 pairs of galaxies scattered across the sky, astronomers noticed an unusual pattern. Neighbors located 'above' or 'below' a massive stellar system contain up to a quarter more oxygen than those lying in the plane of its disk.

Eight hundred million years after the Big Bang, and at the heart of a young galaxy a monstrous engine is already throbbing. A black hole with a mass of ten billion suns devours matter so greedily that its radiation should outshine everything around it. But outside, silence.

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.

Fifteen years of observations by the Gamma radiation telescope Fermi have revealed a crack in the floor of the Galaxy.

In a giant cosmic cradle, the Tarantula Nebula, astronomers took a close look at 122 massive stars, each at least 30 times heavier than the Sun. They measured the nitrogen abundance in their atmospheres, and the picture turned out to be unexpected.

Nearly a decade and a half ago, the Fermi gamma-ray telescope spotted mysterious "bubbles" — giant plasma blobs, as if inflated by invisible lungs, towering tens of thousands of light-years from the Galactic center.

A vast city lights new streetlamps every night. But then a hurricane sweeps in, rips all the fuel from the warehouses, and the lamps go out one by one. Something similar has been spotted by astronomers in a galaxy whose light has traveled 12.5 billion years to reach us.

A river flows toward a whirlpool, but a dam with a notch blocks the way. Most water piles up before the dam, but some, gaining height, leaps over it and falls straight into the funnel. So it is with gas in a galaxy: it streams toward the center but hits a ring of stars and gas, like a dam. Usually, everything stops there, swirling into a dense vortex.

A stream of scorching gas races away from a star, and suddenly stalls, as if it hit an invisible wall. That's exactly what researchers saw when they tried to reproduce a stellar eruption on a laboratory scale. They used a laser to create a plasma jet and shot it through a magnetic field — first weak, then strong, like that of many stars.

A fountain shoots from the center of the city at a speed thousands of times faster than a courier bike. Such a 'fountain'—a stream of gas accelerated to 5500 kilometers per second — has been spotted by astronomers in the galaxy GLIMPSED-329380.

Every galaxy is wrapped in an invisible shell of hot gas, like steam rising from a pot of boiling water. This gas barely glows in X-rays, making it notoriously difficult to measure. Yet it holds the memory of stellar explosions and the galaxy's growth. The new method uses light from a galaxy's bright center.

A distant galaxy, similar to our Milky Way, is blowing gas into space like a hair dryer blowing dust off a table. Seven beams of light from an even more distant object pierced this gas cloud, and astronomers saw that the gas flow is narrow, like a jet from a hose, not wide like a fan.

When a young star ejects jets of gas, they slam into the surrounding cloud like a fist into a pillow. At the impact site, the gas is compressed and heated — creating a shock wave. In this hot zone, atoms and simple molecules collide and assemble into larger compounds, known as complex organic molecules.

When a massive star dies and explodes, it releases not only light but also invisible lightweight particles. They fly out in all directions at nearly the speed of light. Only a small fraction reaches Earth, but each explosion sends its own clump. These clumps stretch along the way: fast particles overtake slow ones, and by the time they arrive, a clump can be spread over tens of thousands of years.

At the heart of nearly every large galaxy lurks a supermassive black hole. As it devours gas, it blasts powerful outflows back into space, like a dragon that can't swallow all its prey and breathes fire. These 'winds' accelerate to thousands of kilometers per second and can sweep away the gas reservoirs from which stars are born.

A quasar is a supermassive black hole at the center of a galaxy that devours matter and shines brighter than all the stars around it. Some of that energy goes into radio emission, which, it was thought, could heat or expel cold gas — the raw material for new stars.

At the center of galaxy VV 340a lies a supermassive black hole — an object with gravity so strong that even light cannot escape it. It emits a relativistic jet: a narrow stream of matter accelerated to near-light speeds.

When Edwin Hubble discovered the expansion of the universe, and Vera Rubin discovered dark matter, the framework of cosmology seemed solid.

At the center of the Milky Way, a giant stellar cauldron boils. Massive stars are born and die there: each death is a supernova explosion, hurling clouds of charged particles into space.