Cosmology

The universe’s hidden stuff could be a mirror world of invisible particles and “dark atoms”

A galaxy 12.5 billion light-years away gives off the light of 300 trillion suns, because its feeding black hole produces enough heat to set the whole galaxy's dust glowing. Lee Billings reports

Galaxies in every corner of the universe have been sending out photons, or light particles, since nearly the beginning of time. Astronomers are now beginning to read this extragalactic background light

The Thirty Meter Telescope can revolutionize astronomy and become a part of the holy mountain’s rich cultural heritage

Astronomers use Kepler telescope to study weather on Jupiter-size planets beyond our solar system

In his latest book Nobel Prize winner Steven Weinberg explores how science made the modern world, and where it might take us from here

A detector fitted on an airplane picked up a signature spike in photons that does not fit any known source of antiparticles

A vast region of space colder than expected is also largely devoid of galaxies, and the two observations are no coincidence. Clara Moskowitz reports

Controversy swirls around a bold proposal for a bigger, better—and expensive—replacement for NASA’s premier space telescope

On April 30, if all goes well, after running out of fuel to fight off orbital decay NASA’s long-running MESSENGER spacecraft will end its mission to Mercury by crashing into the planet’s surface at nearly 4 kilometers per second.

Scientists and astronauts recall the telescope’s finest hours as well as threats to its 25-year existence
 

Imagine a trio of aerobatic aircraft. Over the years they've gotten very good at their routine. But they want to add another five or six or seven members.