From the Milky Way's halo to the far reaches of the cosmos, the two dominating components of the universe are revealing more hints about themselves.

It took 137 hours of staring at the starburst galaxy M82 by a quartet of large telescopes in Arizona, but astronomers have finally confirmed a long-held theory about where the universe's most potent particles originates.

A remarkable new view from the reinvigorated Hubble Space Telescope reveals primordial galaxies seen only about 600 million years after the Big Bang.

A gamma-ray burst seen to occur last April happened in the era of the earliest stars, when the universe was only 630 million years old and the "reionization era" was getting under way. But this news isn't exactly news.

European astronomers are delighted that their new microwave-background spacecraft has successfully begun making its highly detailed map of tiny temperature variations across the sky — the key to revealing insights about how the Big Bang happened and how the earliest galaxies formed.

LIGO, the Laser Interferometer Gravitational-wave Observatory, has just announced its first big astronomy result: Two years of data rule out certain versions of the inflationary-universe theory of what drove the Big Bang.

What spins hundreds of times per second, has 100 trillion times the Sun's density, and spews lethal radiation all over interstellar space? Astronomers are closer to knowing the answers, thanks to NASA's newest deep-space observatory.

Astronomers have turned up a pair of supernovae in extremely distant galaxies (like these) that exploded more than 11 billion years ago, during the universe's infancy. And they did it using a basic technique familiar to thousands of amateur astronomers.

Astronomers are hot on the trail of a new class of cosmic curiosity that's not too small, not too big, but somewhere in between — an intermediate-mass black hole.

Something funny is going on within a few hundred light-years of us, creating high-energy electrons that we don't understand. Recent data from NASA’s Fermi Gamma-ray Space Telescope keep the mystery alive.

The Herschel Space Observatory and the Planck Surveyor, launched May 14th on a single Ariane 5 rocket, will peer deeply into dust clouds and map the microwave background.

An international team of researchers has turned up a galaxy-size object at the dawn of the universe.

NASA has announced finding a gamma-ray burst with a redshift of about 8.2. That puts it 95% of the way back to the Big Bang.

Observing teams have turned up the lowest-mass planet yet detected around a Sunlike star — and a clutch of objects too small to be stars but not really planets either.

It doesn't look like much today, but the far-infrared background radiation coming from all parts of the sky tells of a tumultuous early universe ablaze with starlight.

Take one telescope, use it to record the spectra of 150 galaxies at a time for 4½ years, and what do you get? Awesome 3D maps of deep intergalactic space — and important clues to how the universe works.

Observations from NASA’s orbiting Fermi observatory hint that extremely high-energy gamma rays don't travel at the speed of light. If more observations bear this out, it will rock the foundations of physics, hint at small-scale "space-time foam," and perhaps point the way to a "theory of everything."

A far-off quasar seems to contain two giant black holes hurtling around each other less than a light-year apart. They're doomed to spiral together and join in a literally space-shaking crash — but when?

Astronomers have found something in the very distant universe filling the sky with a radio roar at frequencies they did not expect. No one knows what it is.

Back when the universe was young, a new study finds, galaxies grew their central black holes faster than the holes' starry surroundings. But how?

The universe just isn't making galaxy clusters the way it used to. Compelling new evidence argues that "dark energy" has overwhelmed gravity's influence on forming these largest cosmic structures.

High on the Argentinian pampa, 1,600 water-filled "eyes" await the arrival of the most powerful high-energy particles in the universe.

What was it? While monitoring a cluster of galaxies, the Hubble Space Telescope recorded what seems like a new class of astronomical object brightening and fading over six months.

Astronomers use a novel method of weighing distant galaxies to measure their masses and find that there's more matter than the galaxies' light can easily explain.

Studying the effect of galaxy clusters on the background radiation from the early universe, University of Hawaii astronomers have added to the pile of evidence for dark energy.

Astronomers use the 12-million-kelvin-blaze of a galaxy's central region to measure its supermassive black hole.

Astronomers find that the organic compounds common throughout our galaxy and others suddenly disappear along M101's outer edge.

A subclass of supernovae that fades much faster than expected reveals possible kinks in astronomers' theories of what causes these explosions.

The HST captures a pristine image of various galaxy types grouped together, but what is most intriguing is what the image doesn't reveal.

No two galaxy collisions are alike, as shown in 59 weird images just released by the Hubble Heritage Project.

The visible-light glow of a gamma-ray burst briefly shone at magnitude 5.4, despite its distance of 7.5 billion light-years — more than halfway across the visible universe.

Type 1a supernovas are crucial for measuring how the expansion of the universe has been changing. But no one knows for sure exactly what they are.

The members of a binary black hole in Cancer, one of which is unbelievably massive, look to be on a collision course.

A unique example of gravitational lensing in the universe gives clues to the distribution of dark matter in galaxies.

A ripple in the cosmic background radiation hints at an irregularity in spacetime. . . maybe.

To extract even better star distances, a Cambridge astronomer who took part in the Hipparcos mission has just completed a whole new analysis of the raw data.

Six years ago a radio telescope in Australia recorded a mysterious radio burst that lasted only a tiny fraction of a second and reached Earth from more than a billion light-years away. Astronomers have no idea what caused it.

Minigalaxies of dark matter ought to be everywhere, says the best theory of how the universe came to be. Now they're finally being found.

A billion light-year-wide "hole" in space is a very cold and empty place.

Sizzling with X-rays but mum at radio frequencies, a nearby, on-its-own neutron star is causing astronomers to scratch their heads.

Astronomers have found massive, luminous infrared galaxies 12 billion light-years away. It's not at all clear how they got there.

Two teams of astronomers have won $500,000 for revealing that the universe is growing bigger at an ever increasing rate.

Japanese and European astronomers have proudly unveiled the first all-sky map of the deep infrared sky in more than 20 years.