China joined an elite club on October 14, becoming the third nation to put a human in space. Snug inside the Shenzhou 5 -- a Chinese spacecraft modeled after Russia's Soyuz -- 38-year-old Lt. Col. Yang Liwei orbited Earth 14 times in 21 hours before his entry capsule parachuted to the ground in Inner Mongolia.

Despite grandiose claims, human cloning didn't materialize in 2003. In January legitimate researchers dismissed claims by the Raelian religious cult that two women had given birth to clones. Skepticism also surrounds rogue scientist Panayiotis Zavos, who in April reported he'd created a cloned human embryo.

Dolly, 6

The first mammal cloned from an adult cell, whose 1996 birth raised the specter of human cloning, was euthanized February 14 after developing a lung tumor. Dolly got arthritis early in life, which critics cite as evidence of cloning's potential perils. Waggishly named for Dolly Parton because her genesis was a mammary gland cell, the Finn Dorset sheep is now stuffed and on exhibit at the National Museum of Scotland.



Martha Chase, 75

After years of warnings about the threat of global warming, its potential impact struck home in 2003 with an unexpected death toll from bouts of extreme weather.

No creatures make more sacrifices for science -- albeit involuntarily -- than the mice and rats of lab research. Some 30 million are used each year in the U.S. alone. Reasons: They're small and easily bred, and 99 percent of mouse genes (and likely rat genes too) correspond to human ones. Here, recent rodent-based research.



Fighting AIDS and breast cancer
Investigators at UCSF made a mouse version of HIV, and a U. Wisconsin team created the
first "knockout" rat; it was stripped of a gene that curbs human breast cancer.



Extending the human life span

On February 5, before a rapt U.N. General Assembly, U.S. secretary of state Colin Powell presented the case for invading Iraq. Using an array of evidence -- satellite photos of suspicious activities at missile facilities, sinister audio tapes of Iraqi scientists -- he delivered a clear message: Iraq's weapons of mass destruction program not only persisted but was tailored to evade U.N. inspections. Notably, Powell cited seven mobile labs, each capable of producing "enough dry biological agent in a single month to kill thousands upon thousands of people."

The weak-willed

Are we dreaming? Pinch us: Daily 3.5-ounce doses of dark chocolate lower blood pressure, according to researchers at the University of Cologne, and a team led by molecular biologist David Sinclair of Harvard Medical School reported that an ingredient in red wine extends life span up to 70 percent -- the life span of yeast, that is (future research will test the effect in mice). The beneficial ingredients: natural plant chemicals called polyphenols.



Faithful spouses

Ben Affleck probably wishes he could eradicate every last trace of the Gigli debacle from moviegoers' minds and, appropriately enough, his rebound debut, Paycheck, explores the ramifications of clean-slate mental engineering. In the movie, which is based on the Philip K. Dick story of the same name, Affleck has a lucrative career as an engineer who cracks copyright codes. The catch: his memory is selectively wiped after each job.

For astronomers, 2003 brought some answers, more questions and a deepening conviction: Something strange is happening to the universe. In February a satellite operating a million miles from Earth made a series of measurements that were as baffling as they were precise. A mysterious repulsive force called dark energy accounts for 73 percent of the entire mass-energy of the universe, the Wilkinson Microwave Anisotropy Probe (WMAP) found; 23 percent consists of invisible dark matter, and only 4 percent of the universe is ordinary matter and energy.

Insanely Large Rodent of the Year

The discovery of a buffalo-size guinea pig fossil in Venezuela was announced in September -- the first complete specimen ever found. Scientists suspect Phoberomys pattersoni's size -- 10 feet long, 4 feet tall -- drove it to extinction eight million years ago: Burrowing to escape giant crocodiles was decidedly out of the question.



Most Convenient Genetically Modified Organism of the Year