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A handful of coins drops onto a table — heads and tails land wherever they please. The same goes for an instantaneous snapshot of a quantum chain: in some places a particle is present, in others it is not. But behind the disorder lurks a precise angle. In this work, a chain of particles closed into a ring was considered. It was divided into four arcs: two were measured, two were left untouched.

Cosmic rays aren't rays in the usual sense: they're fast particles bombarding Earth from all directions. Mostly they're protons and atomic nuclei. Their energies vary widely, from modest to fantastically huge. When such a particle heads our way and the Moon or Sun gets in its path, it gets absorbed.

14 seconds. That’s all it takes for a new code to weave the full spectrum of a star, from ultraviolet to near-infrared. This spectrum is not just a rainbow but a detailed tapestry of thousands of dark absorption lines, each left by a specific atom in the star's atmosphere.

Perth residents know: when the daytime heat becomes unbearable, relief arrives from the ocean — a fresh breeze affectionately called the Freo Doctor. The same wind, only on a global scale, decides the fate of cosmic visitors plunging into the atmosphere. A meteorite fall is a two-act spectacle.

In astrophysics, some numbers seem random yet recur with the persistence of a spell. One such number is the ratio of X-ray brightness to H-alpha hydrogen emission in turbulent gas tails. From galactic winds to ‘jellyfish’ slicing through clusters, this ratio steadily holds at around three.

The Universe resembles a dense forest: up close, individual galaxy-trees are visible, gathered into groves, but from a distance everything merges into a solid green canopy. The boundary beyond which the cosmos becomes homogeneous is called the angular scale of homogeneity: it's the size of a patch of sky from which galaxies are distributed evenly.

Light needs space. A camera lens sits several centimeters from the sensor so the rays have room to focus. Now, that gap has been squeezed to the thickness of a sheet of paper, and light still behaves as if it had traveled its rightful centimeters. That's what 'spaceplates' do: flat elements that mimic free-space propagation.

When a heavy nucleus slams into interstellar gas at enormous speed, it shatters into pieces. Those pieces (lithium, beryllium, boron) then fly onward, and their abundance in the cosmic-ray flux depends on how the breakup unfolded. Conventionally, one expected the proportions to shift smoothly with energy, like the taste of soup when you keep adding water.

The future neutrino detector will contain millions of tiny plastic cubes: each the size of a die. They flash when a ghostly particle passes through, and that flash must be captured and measured. But if a cube is warped, has a burr, or a hole in the wrong place, the signal gets distorted, and the detector starts lying. Checking each cube by hand is like sifting through sand on a beach.

If you spill a handful of colorful beads on the floor, they will land differently: some will clump together, others will scatter into corners. Roughly the same way, galaxies of different colors (blue, green, and red) are scattered across the universe. Scientists decided to measure how 'clumpy' their distribution is using a number called the fractal dimension.

Light from a star is not just a stream but a wave that can oscillate in different directions. Ordinary light is like a crowd where everyone waves their arms randomly. But after reflecting off dust grains or passing through a magnetic field, some waves align in a single line, like soldiers in a row.

At night, the sky is never completely black. Even far from cities, the upper atmosphere glows faintly: sunlight makes hydrogen atoms emit a reddish glow that astronomers call geocoronal emission. For a telescope, it's like a fogged-up window: it adds extra light and hinders seeing distant galaxies.

In Chile's Atacama Desert, at an altitude of nearly five kilometers, stands a radio telescope that catches millimeter waves from the depths of space. These waves carry the heat of distant galaxies, but first they must pass through a window — a thin plate of silicon that separates the cold receiver from the warm outside world.

Dust in space is not just grime: it's the raw material for future stars and planets. But how it is distributed in our galaxy has long been a puzzle: dust is hard to measure directly, and it blocks the light of distant stars. Now astronomers have peered through this veil using data on five million stars: their brightness, color, and precise positions in the sky.

Galaxies in the Universe are not scattered randomly: neighboring ones move in the same direction, like a school of fish, while distant ones each go their own way. Where the boundary between 'together' and 'apart' lies has been unclear until now.