Are Aliens Among Us?
In pursuit of evidence that life arose on Earth more than once, scientists are searching for microbes that are radically different from all known organisms
State-of-the-art light microscopy illuminates the exquisite details of life
Window on the Extreme Universe
The GLAST satellite is about to open up
an unexplored region of the electromagnetic spectrum--just the region, in fact, where signs of dark matter and other mysterious phenomena may show up
The Many Worlds of Hugh Everett
After his now celebrated theory of multiple universes met scorn, Hugh Everett abandoned the world of academic physics. He turned to top-secret military research and led a tragic private life
*Supplement: The Many Interpretations of Quantum Mechanics
Puzzle: In Boxes
Our year-end crossword challenges your knowledge of science. Try the printed puzzle or a harder version.
Making Carbon Markets Work
Limiting climate change without damaging the world economy depends on stronger and smarter market signals to regulate carbon dioxide
* Supplement: Extended version