What Is a Planet?
The controversial new official definition of "planet," which banished Pluto, has its flaws but by and large captures essential scientific principles
The Power of Riboswitches
Discovering relics from a lost world run by RNA molecules may lead to modern tools for fighting disease
The Mississippi's Curious Origins
A mountain range once separated the continental interior of the U.S. from the Gulf of Mexico. Some clever geologic sleuthing has revealed how that barrier was breached, allowing the river to reach the Gulf
Is Ethanol for the Long Haul?
Ethanol could displace gasoline, but it won't pay off until we find a way to distill cornstalks, not corn
Evolved for Cancer?
Natural selection lacks the power to erase cancer from our species and, some scientists argue, may even have provided tools that help tumors grow
Better Ways to Target Pain
Improved understanding of the chemical pathway on which aspirin and Vioxx act may lead to analgesics with fewer side effects
A Robot in Every Home
The leader of the PC revolution predicts that the next hot field will be robotics