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astronomy

astrophysics

Colliding Black Holes Tell New Story of Stars

Just months after their discovery, gravitational waves coming from the mergers of black holes are shaking up astrophysics.

Abstractions blog

LIGO Reports Second Black-Hole Merger

The spokesperson for the Laser Interferometer Gravitational-Wave Observatory called it “a promising start to mapping the populations of black holes in our universe.”

Abstractions blog

A Glimpse Through a Cosmic Keyhole

What could cause galaxies millions of light years apart to all spew material in the same direction?

astrophysics

After Black Holes Collide, a Puzzling Flash

A satellite spotted a burst of light just as gravitational waves rolled in from the collision of two black holes. Was the flash a cosmic coincidence, or do astrophysicists need to rethink what black holes can do?

Q&A

From Einstein’s Theory to Gravity’s Chirp

The path from a revolutionary set of equations to the detection of gravitational waves was strewn with obstacles and controversy, explains the physicist Daniel Kennefick — and the struggle continues.

astrophysics

Gravitational Waves Discovered at Long Last

Ripples in space-time have been detected a century after Einstein predicted them, launching a new era in astronomy.

astrobiology

Scientists Debate Signatures of Alien Life

Searching for signs of life on faraway planets, astrobiologists must decide which telltale biosignature gases to target.

Q&A

Searching the Sky for the Wobbles of Gravity

The physicist Gabriela González is on the cusp of finding the first direct evidence of gravitational waves — soundlike wobbles in space-time produced by black holes and their kin.

astrophysics

The Particle That Broke a Cosmic Speed Limit

Physicists are beginning to unravel the mysteries of ultrahigh-energy cosmic rays, particles accelerated by the most powerful forces in the universe.