photosynthesis

In a dark room, you can hold a glowing sphere without touching it: walls of light push it away but do not burn it. That is roughly how the trap built in Rio de Janeiro for yeast cells works. A conventional optical tweezer, that is, a focused laser beam, acts like tweezers made of light, but the light itself pierces the cell from side to side.

Turn off the stove, and water stops boiling almost instantly. In the world of catalysis, researchers expected a similar picture: stop the reaction, and all intermediate particles vanish right away. But fresh observations of platinum nanoparticles tell a different story.

The lifetime of the entangled triplet pair in the protein is about 60 picoseconds, which is eight times longer than in solution. Sunlight is like a continuous stream of balls flying at a wall.

In dark interstellar clouds where new stars are born, chemistry starts with a tiny particle — the trihydrogen ion (H₃⁺). It collides with other atoms and sets off a cascade of reactions that build ever more complex molecules. For a long time, it was thought that the main reaction producing it, H₂⁺ colliding with H₂, only happens in the gas phase.

In the black depths of space, on the surfaces of tiny icy dust grains, a quiet construction is underway. There, where temperatures drop to near absolute zero and harsh radiation abounds, the ordinary amino acid glycine, the simplest protein building block, links up with itself.

A tuning fork struck once rings pure and long. But if you shake the fork itself while it sounds, the tone wavers and dies out quickly. Something similar happens to electrons in any piece of matter. Atoms in a lattice never stay put: thermal vibrations keep them jittering.

A sunbeam hits a leaf, and inside, a relay race begins. Energy hops from one molecule to the next until it reaches its goal. In photosystem II (a protein complex that kicks off photosynthesis), the runners are pigment molecules: chlorophylls and pheophytins.

Imagine a packed subway car at rush hour. Passengers don't just stand there: they breathe, release moisture, squeeze toward exits, and sometimes get stuck in doors, blocking movement. Now imagine these passengers can remodel the car's walls, add handrails, or turn the floor into gel.

In the coastal shallows, where water retreats and returns, life follows the rhythm of the sun. The brownish film on the mud's surface is not just dirt but a dense community of tiny diatoms. By day they get plenty of light for photosynthesis, but when the sun gets too intense, a chemical storm brews inside the cells.

Imagine an artist whose canvas is an entire planet, and whose palette is molecules drinking starlight. His brush is billions of years of evolution, and his painting is a spectral portrait visible even from another star system.

Every year, the food we eat costs humanity tens of millions of years of life due to unhealthy diets. At the same time, a third of all greenhouse gases warming the planet are produced along the journey from farm to plate. It seems obvious: switch to healthier eating, and we'll save the climate and improve our health. But new research shows these two goals don't always go hand in hand.

Billions of tiny motors hum inside every living creature. Cells ceaselessly pump substances, burn sugar, and build new proteins, and all this invisible motion warms us from within. To maintain order, life must dissipate heat into the environment, like a stove that never goes out. The power of this internal heating is almost independent of size.

A typical photon source can be likened to a club entrance with a single bouncer. He tries to let people in one at a time, but occasionally couples sneak past. Physicists call this the purity problem: photons must arrive strictly solo, otherwise quantum computing breaks down.

Yeast are trapped in a clear gel, like raisins in jelly. They can't move on their own, but soon they start rising to the top. The secret lies in their own homemade fizz. During fermentation, yeast release carbon dioxide. In a thick medium, the gas doesn't escape but accumulates until bubbles form.

Dirty water laced with antibiotics isn't just waste: it's a hidden energy source. Chemists built a material from two components: titanium oxide nanorods (the white pigment in paints and sunscreens) and carbon nitride nanosheets.

Conventional solar panels convert light into electricity, but here light splits water into hydrogen and oxygen. Hydrogen is a clean fuel, but the process is slow. To speed it up, helper substances that donate electrons are added. Often this is alcohol, but it's a shame to waste it.

In a thin film of water squeezed between two glass plates, bacteria live. Oxygen reaches them only through one wall, like air entering a room through a single window. When bacteria are few, they pay no attention to this: some stick to one wall, some to the other, and the picture is symmetric. But once they multiply, everything changes.

The tiny green alga Chlamydomonas spends its life rowing with two flagella toward light, like a swimmer heading for shore. It senses light with a photoreceptor protein, and behind it lies a red spot — the 'eyespot'—which casts a shadow and helps the cell figure out where the light is coming from.

Oxygenic photosynthesis requires splitting water. It's kind of like a water wheel: to make it spin, you need a strong current. Light acts as the current, and light particles are the streams. For red dwarfs, the most common stars, the light is "cool" and weak — the streams barely move the wheel.

When a sunbeam hits a leaf, a relay race begins inside it. The energy of light passes from one chlorophyll molecule to the next until it reaches the reaction center — the place where the chemistry of life kicks off. This relay runs with astonishing accuracy: nearly every quantum of light finds its way.

Light from an ordinary bulb is a stream of individual photons, like drops from a faucet. But there is also light where photons come in pairs, like twins walking together. Such grouped light has long been desired for measuring distances and imaging objects hidden around corners. But sources of this light were either too dim, or their flashes too short for ordinary detectors to catch.

Cometary ice slams into the young Earth. The pressure at the impact point is like stacking six aircraft carriers on your thumbnail. In the lab, such conditions are reproduced by squeezing a tiny sample between two rotating anvils. This time, adenosine monophosphate — one of the letters of future RNA — was placed under the anvils.

Chemistry has two worlds: in one, the catalyst is a solid particle and the reaction happens on its surface; in the other, it's a dissolved molecule where everything occurs around a single metal center. These worlds rarely meet. But in a new study, they collide. The researchers took iron oxide, a black powder used in magnetic tapes, and scattered single rhodium atoms across its surface.

In the air we breathe, invisible chemical events are constantly unfolding. One of them is the birth and instant death of a particle with the formula H₂COO. Known as an 'intermediate,' it appears for a split second when ozone molecules collide with organic compounds, then immediately shatters into simpler fragments.

Dissolve a few salts and formaldehyde in a glass of water. After a while, the liquid spontaneously separates: droplets with membranes appear, like tiny bubbles. Inside each droplet, chemical transformations occur, and the droplet itself grows, absorbing material from the surrounding solution. These droplets are not just bubbles.

In every leaf, in the light, a factory works that splits water into oxygen and hydrogen. The oxygen goes into the air we breathe, and the plant uses the hydrogen for food. The heart of this factory is a protein complex with four manganese atoms and one calcium atom.

On the exoplanet TRAPPIST-1, oxygenic photosynthesis, the process by which light energy is converted into chemical energy with oxygen as a byproduct, is losing the race for survival. This M-dwarf star emits mostly in the infrared, not in the visible range like the Sun.

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.

Living cells continuously exchange light signals — a billion times fainter than daylight. It's like a whisper picked up by ultra-sensitive instruments. A healthy cell whispers rhythmically, a cancerous one — haltingly, but with a long memory of previous flashes.