SA Special Editions

The galaxy is teeming with planets. Scientists are straining to peer into their atmospheres to seek signs of extraterrestrial life

The sun was born in a family of stars. What became of them?

All stars are born in groups but then slowly disperse into space. A new theory seeks to explain how these groups form and fall apart or, in rare cases, persist for hundreds of millions of years

Some say its glory days are long gone, but the universe has life in it yet. Brand-new types of celestial phenomena will unfold over the coming billions and trillions of years

Tipping the scales at less than about a million suns in mass, middleweight black holes may hold clues to how their much larger siblings, and galaxies, first formed

A shadow cosmos, woven silently into our own, may have its own rich inner life

By the latest estimate, the observable universe contains 200 billion galaxies. Astronomers wonder: Why so few?

Dark energy does more than hurry along the expansion of the universe. It also has a stranglehold on the shape and spacing of galaxies

Is the theory at the heart of modern cosmology deeply flawed?

Proof of parallel universes radically different from our own may still lie beyond the domain of science

Our universe may have started not with a big bang but with a big bounce—an implosion that triggered an explosion, all driven by exotic quantum-gravitational effects

Total energy must be conserved. Every student of physics learns this fundamental law. The trouble is, it does not apply to the universe as a whole

Deep down, the particles and forces of the universe are a manifestation of exquisite geometry

An experiment going up outside of Chicago will attempt to measure the intimate connections among information, matter and spacetime. If it works, it could rewrite the rules for 21st-century physics

To learn how the universe evolved over time, a space telescope gazes back to the earliest galaxies ever observed