SUNSET: 
Supernova Mystery Remains Just That
Despite a recent claim, astronomers still don't understand an important class of exploding stars.
Spiral Galaxies Exist — But Why?
New observations of the early universe, combined with models of how galaxies formed and collided in the eons since, are helping cosmologists understand why so many beautiful pinwheels dot the sky.
WMAP Refines "Precision Cosmology"
With seven years of data, the WMAP cosmology satellite has refined the age of the universe and other key cosmic parameters. The results strengthen the "standard model" of inflationary cosmology.
Dark Matter and Dark Energy Update
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.
A Breeding Ground for Cosmic Rays
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.
Hubble Goes Deep(est) Again
A remarkable new view from the reinvigorated Hubble Space Telescope reveals primordial galaxies seen only about 600 million years after the Big Bang.
Blast from the Very Far Past
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.
Planck Sees "First Light"
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.
New Limits on the Big Bang
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.
Fermi Tracks Gamma-ray Pulsars
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.
Image Stacking Nets Ancient Supernovae
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.
New Candidates for Midsize Black Holes
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.
Dark Matter or Pulsars? Fermi is on the Case
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.
Planck and Herschel to Probe Inflation and Starbirth
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.
Introducing "Himiko," the Primordial Blob
An international team of researchers has turned up a galaxy-size object at the dawn of the universe.
The Farthest Thing Ever Seen
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.
Bantamweight Planet and Three Dwarfs
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.
A Murky All-Sky Background Is Resolved
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.
Best-Ever Southern-Sky Galaxy Survey
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.
Gamma-Ray Burst Hints of Space-Time Foam
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."
