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astronomy
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.
astrophysics
Strange Stars Pulse to the Golden Mean
Nature has revealed peculiar mathematical objects that connect order and chaos.
cosmology
Peering Into the Early Universe
Three “extremely large telescopes” poised to begin observations within a decade could help answer some of the universe’s oldest and best-kept secrets.