exoplanets around red dwarfs

The family album of this stellar pair has been filling up for 45 years, but the pictures were blurry and the captions contradictory. Now astronomers have pulled out the old photographs, taken new sharp shots, and put everyone back in their proper places. Gamma Cephei is a bright star visible to the naked eye, and it has an invisible companion that orbits it every 70 years.

Astronomers catch distant planets by the trembling of their stars: an invisible companion tugs the star toward us and away, and its light subtly shifts in color. But that trembling tells only half the truth. If the planet's orbit is tilted to our line of sight, only part of its weight rocks the star, so telescopes reveal not the true mass but its shadow.

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.

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.

On a sunny street, there's a house with a big family: a giant father who always sits by the window and a small child running around the yard. That's the TOI-4468 system: a gas giant hot Jupiter hugs the star, while a bit farther out circles a sub-Neptune — a planet smaller than Neptune but larger than Earth.

The JWST space telescope aimed its lens at the scorching rocky world 55 Cancri e, and spotted a dense gas envelope. But the cooler TRAPPIST-1 b, which orbits a dim red dwarf, showed no envelope: just bare rock. The picture came out upside down: hot planets hold onto atmospheres, while cooler ones lose them.

A telescope stares at a star for many nights in a row. Somewhere in the stream of light hides a tiny dip in brightness — an Earth-sized planet briefly blocking part of the star. Such a dip lasts a few hours and repeats once a year or less. Catching it is like hearing a single quiet click in a noisy hall.

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.

A lighthouse that blinks not every second but once every few minutes or even hours. That is exactly how long-period radio transients behave — cosmic sources discovered only recently.

The birth of a moon is a cosmic car crash. Two young planets collide, and a cloud of scorching debris swirls around the surviving world. From this disk, like clay on a potter's wheel, a satellite gradually takes shape. That's probably how our Moon came to be.

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.

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.

Tabby's Star, a beacon in the cosmic sea, has baffled astronomers since 2015. Its light flickered not in the rhythm of planets, but as if scattered by a storm — deep dips, sharp spikes. But amid this chaos, a smooth, nearly perfect dip was found. The eye of the storm.

In a single star system, two teams of planets orbit. Some follow neat paths, like figure skaters on an ice rink, avoiding collisions. Others crowd together, their trajectories cross, and sooner or later a cosmic accident occurs — a giant impact.

Every 165 days, the giant planet dives toward its star, nearly grazing its fiery corona, then flies off into the icy void. This is TIC 241249530 b — an exoplanet with a record eccentricity of 0,94.

In 2024, the team led by David Charbonneau pointed the Magellan telescope with the WINERED spectrograph at LHS 1140. During transit, high-resolution spectroscopy caught the absorption line of metastable helium at 10833 Å.

The light of a distant star carries within it the silent hum of the atmospheres of planets orbiting it. For a long time, capturing it was like trying to make out a whisper over a roaring waterfall. But with the advent of the 39-meter Extremely Large Telescope (ELT) and the ANDES spectrograph with a resolution of 100,000, this task is no longer hopeless.

When a distant planet passes in front of its star, it briefly blocks part of the light. Astronomers call this a transit and judge the planet's size by the depth of the dip. But light has a property: a massive body acts like a lens. Even a giant planet can slightly bend the star's rays, and the dip becomes a bit shallower than you might expect.

A quarter-century ago, Michel Mayor and Didier Queloz discovered the first hot Jupiter, and shattered all the rules of planet formation. A gas giant on a days-long orbit couldn't have formed next to the star: it's far too hot and lacks building material. So, it must have been born far away and then migrated.

In 2024, the Hephaestus project sifted through millions of stars and flagged a few dozen suspicious ones: they shone brighter in the mid-infrared than a normal red dwarf should. Two of these candidates, labeled D and E, looked especially tantalizing, as if an invisible heater were working next to the star.

A spotlight blazes straight into your eyes, and a few steps away a tiny firefly flickers. That's roughly what it's like hunting for an Earth-like planet around a neighboring star: the planet is a hundred million to ten billion times fainter than its star, and in the sky they almost merge into a single point.

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.

The gravitational dances of celestial bodies long remained silent to astronomers. We learned to catch the shadows of planets against stars with the transit method — a breakthrough that delivered thousands of worlds thanks to William Borucki and his Kepler telescope.

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.

Remember the sensational comet 1I/‘Oumuamua — the first object to come to us from another star? Its hyperbolic trajectory left no doubt: it was a wanderer from the interstellar void. But astronomers wondered: could some of these visitors not be strangers at all, but our own, escaped from the Solar System millions of years ago?

Every star is a living archive, and its spectrum a multilayered manuscript. Over billions of years, the history of the galaxy is written into it: the galactic chemical evolution of the Milky Way leaves a smooth trace in elemental abundances.

The light of a distant star is no perfect beacon. Passing through the gravitational field of another star, it bends, splits, and magnifies, creating a fleeting Einstein ring in the sky. This is how gravitational microlensing manifests, predicted by Fritz Zwicky back in the 1930s.

Like an exquisite clockwork mechanism, a multi-planet system responds sensitively to the slightest nudge. And when the star at the heart of this mechanism dies, shedding its envelope and turning into a white dwarf, even a modest kick at a speed of 0.75 km/s can trigger a cascade of events, flinging entire worlds into interstellar emptiness.

In deep space, 95 parsecs from Earth, nature is assembling a planetary clock. The model HD 114082 is a prototype, only 15 million years old. Two massive pendulums — exoplanets b and c — are already swinging with periods of 225 and 314 days, but the whole mechanism is still covered in the construction dust of a debris disk.

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.

A ball, almost weightless for its size, circles its star every four days. Planet TOI-2195 A b is a real riddle: by mass it's slightly heavier than Neptune, yet bloated to Jovian volumes. If there were an ocean big enough, this exoplanet would float on its surface like a giant inflatable ball.

When a star dies, it turns into a white dwarf — a dense ball of carbon and oxygen the size of Earth. Predicted by Subrahmanyan Chandrasekhar, these objects were long thought to be lifeless graveyards.

The Martian surface is a place where anything alive quickly dies. Cosmic rays and ubiquitous oxidizers sterilize the top layer of soil. But dig a little deeper, and the picture changes. There, beyond the reach of ultraviolet light, a zone suitable for life may lurk. This zone runs on a strange fuel — radiation.

Some 158 light-years away, around the dim star TOI-6894, a red dwarf, a planet moves leisurely. Its year lasts less than two Earth days, yet it is a cool world with an equilibrium temperature around 420 K, just a bit warmer than a sauna.

Using James Webb, astronomers 'fished out' a third giant planet from the murky dust disk of the star β Pictoris. Two others were already known, but this one was hiding in the bright light, like a fish in muddy water.

A scorching rocky planet is like a pot of boiling soup, except its lid is the atmosphere. Gases escape from the magma, wrap the world in a thick blanket, and in turn influence how quickly the celestial body cools. For GJ 1132 b, which orbits so close to its star that a year lasts just one and a half Earth days, this connection is especially important.

A pot of boiling soup is shaken hard — the liquid sloshes, waves crash against the walls. Something similar happens inside a gas planet when it swings past its star on an elongated orbit. The star's gravity excites powerful internal waves in the planet, known as tidal fundamental modes. These waves can completely change the planet's fate.

A cosmic sprinter on a short track: that's how you might describe planet GJ 367 b. It whips around its star in just 7.7 hours. This world is slightly smaller than Earth but has a personality: it was once thought to be nearly a solid ball of iron.