type ia supernova

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.

The universe is a vast, dark ocean. We see only the glowing foam on its surface — stars and galaxies. But hidden in the depths are two invisible forces: dark matter, which with its gravity keeps galaxies from flying apart, and dark energy, which, on the contrary, pushes space itself apart, making the universe expand faster and faster.

17 supernovae from the ZTF DR2 sample lit up ahead of schedule. In the first hours and days after the explosion, they emitted more light than standard models predict. Astronomers compare this to a Bickford fuse: before the blinding flash tears across the sky, a precursor spark runs through the outer layers.

Deep underground, in the silence of a cryostat (a cooled container), lie crystals of lead that once belonged to an ancient Roman ship. This material barely emits background radiation — over two thousand years, unstable isotopes have decayed, leaving it perfectly clean for hunting the rarest events.

On August 6, 1181, Chinese astronomers spotted a new star in the constellation Cassiopeia. It shone for 185 days, slowly fading, and then vanished, leaving only a record in the chronicles. Today, at its location, there is a hot white dwarf — a compressed stellar core with no nuclear reactions, heated to tens of thousands of degrees.

The hunter of ancient light, the James Webb Telescope, aimed its mirrors at a tiny patch of sky and caught a strange beacon. The object, with the working name beacon_1420-$$5253_{4770}$$, flashed and faded. At first, it was logged as a candidate for the most distant galaxy, as if we were seeing it just 300 million years after the big bang.

The cosmological orchestra doesn't tune to a single tuning fork. There are two groups of instruments: one listens to the hum of the young universe — the cosmic microwave background, while the other reads notes from mature galaxies and supernovae.

A massive star doesn’t simply fade away — it blows up as a supernova, leaving behind an expanding remnant and a wildly spinning neutron star — a pulsar. In this cosmic storm, astonishing patterns emerge, and the 'Nimbus'–'Thunder' system is a dazzling illustration.

The universe is full of the invisible. We know about dark matter from galaxy rotation and gravitational lensing, but its nature has eluded us for a century.

In the constellation Scorpius, 3,000 light-years from Earth, a dead star steals matter from a living one. A white dwarf in the system IGR J17014-4306 — a superdense carbon-oxygen ball with the mass of the Sun but the size of Earth — siphons hydrogen from a normal companion star.

Type Ia supernovae are the final, blinding chords in the symphony of stellar evolution: when a white dwarf crosses the limit predicted by Chandrasekhar, it explodes so brightly that for a moment it outshines an entire galaxy.

Two burned-out stars, each about the size of Earth but heavier than the Sun, spiral ever closer until one crashes into the other. The impact triggers a thermonuclear explosion, giving birth to a type Ia supernova. Such flashes serve as cosmic beacons for measuring distances across the universe. Yet the details of their origin remain hotly debated.

A campfire that always blazes up to the same temperature — whether you toss a match into the center of a log or light several kindling sticks at the edges. That's roughly how Type Ia supernovas behave: cosmic explosions that astronomers use as rulers to measure distances across the universe.

Imagine inflating a balloon. It expands quickly at first, then slows down, and then suddenly speeds up again, as if someone gave the pump another squeeze. That's what seems to be happening to our universe.

A match flares from both ends. First the head ignites, and a moment later the flame engulfs the wooden stick. Something similar may happen in some Type Ia supernovae — except the match is a white dwarf (a star the size of Earth), and the flame is a thermonuclear explosion.

A lighthouse blinks steadily once per second. If it moves in a circle, its flashes arrive sometimes a bit early, sometimes a bit late, and they give away an invisible companion. That's exactly how astronomers exposed the hidden partner of the star IY Lyrae. IY Lyrae is a pulsating variable star in the thick disk of the Galaxy.

Two lamps in a shop window: one glows with a cool, bluish light, the other a bit warmer and yellower. That's roughly how the two types of supernovae, Ib and Ic, look when astronomers view them through a telescope.

In 1987, astronomers saw a supernova flare up in a neighboring galaxy — the Large Magellanic Cloud. It was a rare gift: the explosion was close enough to catch not just light but also neutrinos, those nearly undetectable particles that pass straight through Earth.

Be stars are rapidly rotating luminaries with bright gas disks. Usually, a companion star spins them up: mass flowing from the neighbor whirls the star like a bullet in a rifled barrel. But there are also lone Be stars without a partner: their origin long remained a mystery. New research shows that solitaries can be born from a supernova explosion.

A distant lamp shines through uneven glass. The glass bends the rays, and instead of one flame on the wall, several appear — some brighter, some fainter. In much the same way, a massive galaxy bends the light of an exploded star. There was one explosion, but the images show four glowing points.

Cosmologists have measured how fast distant galaxies are receding in different parts of the sky. To do this, they used two kinds of "cosmic rulers": galaxy clusters and a certain type of supernova explosion. Both methods showed the same thing: in one direction, the Universe is expanding slightly faster than in the opposite direction.

When a massive star runs out of fuel, it sheds its hydrogen envelope and explodes, like a final, desperate exhale. That’s exactly the kind of supernova (type Ib) astronomers observed. 62 days after the blast, in the cooling debris, they caught a faint infrared glow: it turned out to be the signature of carbon monoxide (CO).

Deep in the constellation Aquila lies a nebula that looks like an expanding bubble. It is inflated by a tiny star the size of a city — a pulsar that makes several rotations per second and loses rotational energy. Usually, such bubbles shine exactly as brightly as their pulsar is powerful.

Deep inside a dying star, just before it goes supernova, nuclear reactions determine which chemical elements will be scattered across the cosmos. One such reaction is the collision of an oxygen nucleus with a proton, producing a nitrogen nucleus and an alpha particle (a helium nucleus).

Deep in the Galaxy, runaway stars are sometimes born. A monstrous force, a supernova explosion, flings them from their usual place. One such wanderer has recently been found: a star of the LP 40-365 class, a fragment of a white dwarf that survived an incomplete explosion.

Light from a distant star travels to us for billions of years, and during that time the universe has time to expand. How can we check that we correctly understand this journey? Astronomers use two 'rulers': supernova explosions, which shine with a known brightness, and fast radio bursts — short, powerful pulses of radio waves from other galaxies.

In distant galaxies, old stars swell and redden. Among them are two groups that act like lighthouses: some have just ignited helium burning, while others are already burning carbon and oxygen.

A red giant in the constellation Cygnus has swelled so much that its outer layers are spilling onto a small but heavy neighbor — a white dwarf. The gas swirls around the dwarf like water down a bathtub drain, falling onto it. But in CH Cygni, this flow is not calm: every 682.5 seconds, the X-ray emission flares and fades.

A pair of stars circles each other. One is a dense white dwarf the size of Earth but with the mass of the Sun. Its companion is a regular star that transfers material onto the white dwarf. From time to time, the accumulated gas erupts like a giant hydrogen bomb, making the star thousands of times brighter for a while.

In 2013 and 2020, the same telescope in Hawaii looked at the remnant of an exploded star — Cassiopeia A. The images were taken in the light of glowing iron, as if photographing invisible streams of metal flying through space. Over seven years, astronomers found 263 dense clumps — debris ejected by the explosion.

Astronomers caught the young planet AU Mic b in the act of hiding behind its star. The Spitzer telescope tracked its infrared glow: as the planet slipped behind, the system's total light dimmed slightly. The dip was just 171 parts per million, like a single drop of ink in ten buckets of water.

Sometimes you find a movie ticket from three years ago in the pocket of an old jacket. You can't reconstruct the time from it, but you can figure out where the owner went. The same goes for hot subdwarfs — tiny stars in the late stages of life that shine mostly in ultraviolet. Their light is like that ticket: it tells you about the past, but reading it is tricky.

When a distant star explodes, its light travels toward us for billions of years. Astronomers measure how dim it appears and use that to calculate the distance. Usually, this involves complex models with dark energy and other mysteries.

Massive stars end their lives in a grand explosion — a supernova. Their cores collapse into a neutron star (a super-dense ball where a teaspoon of matter weighs a billion tons) or a black hole. For a long time, the most common type of such outbursts was thought to be the domain of solitary stars. However, supernova SN 2018gj broke the rule.

Some superluminous supernovae show a bright oxygen imprint in their light and expand rapidly, while others do not. It seemed like different phenomena. But supernova PTF12dam broke the rules: as its brightness grew, its oxygen signature changed, shifting from one type to another.

Type Ia supernovae are the 'standard candles' of cosmology: their peak luminosity is nearly identical, allowing distances to be determined from apparent brightness — the fainter the object, the farther away it is.

Astronomers use Type Ia supernovae — thermonuclear explosions of white dwarfs — as 'standard candles': their peak luminosity was long thought to be the same everywhere in the universe.

A firefly blinks for one ten-billionth of a second somewhere above the Siberian taiga. Seeing such a thing is impossible, but the TAIGA-HiSCORE array, spread across a valley in the Tunkinsky district of Buryatia, tried to catch exactly such flashes — not from insects, but from the depths of space.

In the quiet harbor of the Local Bubble, a rarefied cavity of hot gas around the Sun, an explosion recently thundered. A supernova went off tens of parsecs away, and its echo still lingers in the neighborhood, reshaping the cosmic-ray landscape.