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Measuring distances in the universe is no easy task. Almost all methods rely on light, which can be absorbed by dust, scattered, or distorted along the way. It's like trying to spot a distant lighthouse through fog and haze. Neutrinos are a different story. These ghostly particles pass through anything without noticing obstacles.

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.

A research probe is planned for the nearest black hole — a region of spacetime whose gravity traps even light. After a hundred years of flight, the spacecraft will enter orbit around the mysterious object to answer a key question: are we looking at a black hole or a neutron star — the ultra-dense remnant of a massive star, compressed to nuclear…

Every 1151 years, seven planets of the Solar System, from Mercury to Neptune, find themselves at almost the same points in their orbits. Their positions scatter by less than a degree, as if the celestial mechanism is wound to the same tune. This rhythm was discovered by comparing planetary positions over 2600 years using precise tables of celestial motion.

The Sun is not a perfectly steady lightbulb. Its brightness quivers slightly: it dims a bit, then brightens. For Earth's climate, even slow variations stretched over thousands and millions of years matter. They could have left their mark in the geological record of the last 540 million years. Astronomer [scientist:A. M.

For ten hours, the star HD 137010 dimmed a little, like a lamp with a speck of dust on it. The K2 telescope caught this in 2017, and in all the observing time, it happened only once. Astronomers realized: a planet had passed in front of the star. This way of finding worlds is called the transit method. When a planet crosses the star's disk, the star briefly fades.

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.

Only by passing in front of a star did Chiron reveal its secret. Three icy hoops encircle the 200-kilometer body — a hybrid of comet and asteroid. Previously, they were only hinted at by spectra of reflected light and brightness fluctuations.

The Solar System takes 210 million years to complete one orbit around the center of the Milky Way. The last time we were on this same side of the Galaxy, early dinosaurs were roaming the Earth. That number, 243.72 km/s, has now been refined thanks to rare stars that streak through the Galaxy like cannonballs.

Every second, dozens of particles from space fly through each of us. Most are light protons, but there are also heavier atomic nuclei: carbon, oxygen, iron. They are born in stellar explosions and travel to Earth for millions of years. Their energy can be staggering: a single particle can carry as much as a tennis ball on a serve.

Cosmic rays are charged particles that fly to us from the depths of the Galaxy. If you plot how many particles arrive at each energy, the line runs smooth, then suddenly drops sharply.