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An octopus waits with tentacles spread wide. No central controller directs its arms, but the moment prey touches one, all eight wrap around it. Physicists have recreated a similar trick in the lab with a body that has neither neurons nor muscles: a star polymer with self-propelled arms. The polymer was assembled from small cylindrical vibrobots on a vibrating plate.

Boiling water in a pot is a good place to start. Bubbles of steam rise, pop, and the surface settles down. Something similar might have happened in the first moments of the universe's life with a special field filling space: bubbles of a new phase inflated and collided, like islands of steam in liquid.

The Orion Nebula is a showcase of astrophysics, a laboratory for studying star formation right in our backyard. For over a century, its light has been split into spectra, and each forbidden line whispers its own version of how many electrons per cubic centimeter.

Blazars are long-lasting beams from black holes at the centers of galaxies. Gamma-ray bursts are the briefest flashes from supernova explosions or neutron star mergers. The former act like eternal spotlights, the latter like camera flashes.

A lump of dark matter drifts through the void — invisible, almost intangible. No one knows what it's made of, but a new study suggests viewing it as a drop of quantum liquid. Two kinds of fermion particles — call them "heavy" (ψ) and "light" (χ)—exchange signals via a third mediator particle (φ), like floats tied to a single line.

In the scorching solar corona, where temperatures soar past a million degrees, float cold, dense clouds — solar prominences. They hang for weeks, neither falling nor dissolving, like icebergs in a boiling ocean. How they got there is a question that has puzzled astronomers for decades.

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.

Dough rises faster when it already contains yeast. Similarly, galaxies may have assembled faster if they already had black holes inside. Astrophysicists considered a scenario where the universe contained primordial black holes from the very beginning — objects that could have formed in the first instants after the Big Bang.

Light from the galaxy PAN-z14-1 began its journey when the universe was 400 million years old — a cosmic infancy. The expansion of space made it travel to us for nearly 13.5 billion years.

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.

A few hundred million years after the Big Bang, the universe resembled an endless dark ocean, shrouded in a thick fog of neutral (non-ionized) hydrogen. Then something dispersed the gloom: ultraviolet radiation knocked electrons out of atoms, making the gas as transparent as pure water.

Life began with molecules akin to natural sunscreen — based on carbon, they soaked up the mild ultraviolet of the young Sun and turned it into heat. This way of dissipating energy wasn’t just heating: it made molecules self-organize, like chefs kneading structured dough out of a chaos of ingredients. But ultraviolet is a finicky tool.