WASHINGTON, 2:58 p.m. Dec. 28 (AP)
NASA takes a major step toward returning astronauts to space when engineers this week ship an improved rocket fuel tank that has been refitted to avoid the falling debris that caused the destruction of Columbia and the death of seven astronauts.

National Aeronautics and Space Administration officials said that the redesigned fuel tank, a massive vessel that supplies propellant for the launch of the space shuttle, will start a barge trip on Friday from a Mississippi assembly plant to the launch site on Florida's east coast.

Dec. 27 (UNION-TRIBUNE)
Study says protein p53 weeds out mutations: San Diego scientists have identified a protein in embryonic stem cells that helps weed out mutations as the cells proliferate. Its action may protect a developing embryo from DNA damage that could lead to cancer later in life.

PORTLAND, Ore., 1:21 p.m. Dec. 28 (AP)
Tsunami researchers scramble to dispatch survey team: Tsunami researcher Harry Yeh was at home late Saturday night when he learned that a massive earthquake had struck Sumatra, generating a deadly wave that swept across the Indian Ocean and Bay of Bengal.

PHOENIX, 2:33 p.m. Dec. 28 (AP)
Endangered black-footed ferrets make comeback in Arizona: Endangered black-footed ferrets are reproducing more and surviving longer in the wild in Arizona than they have since recovery efforts began nearly a decade ago, according to wildlife biologists.

KOROLYOV, Russia, 9:48 a.m. Dec. 26 (AP)
Russian cargo ship docks at the international space station, delivers sorely needed supplies: A U.S-Russian crew got some belated Christmas turkey and vital supplies Sunday when an unmanned cargo ship docked at the international space station, ending a shortage that had alarmed officials at home and forced astronauts to ration supplies.

LOS ANGELES, 12:01 a.m. Dec. 24 (AP)
Asteroid gets initial elevated risk rating, but impact unlikely: A recently discovered asteroid that crosses Earth's orbit has been given a higher impact hazard rating than any other seen so far, but scientists say it is likely the risk will be eliminated as further observations refine projections of its orbit.

MOSCOW, 8:04 a.m. Dec. 25 (AP)
Russian cargo ship set to dock to the international space station: An unmanned Russian spaceship on a vital supply mission approached the international space station, preparing to dock Saturday with its cargo of food for the two-member U.S.-Russian crew, who have been forced to ration their dwindling supplies.

HADLEY, Mass., 10:27 a.m. Dec. 24 (AP)
American eel – not exactly a 'warm, fuzzy species' – may be bound for federal protection: It is one of the creepier creatures on Earth – a squirming, snakelike fish bound for no real glory beyond its role in sushi or as bait dangling from a fisherman's hook.

SAN FRANCISCO, 12:09 a.m. Dec. 23 (AP)
California company sells cloned cat, generating ethics debate: The first cloned-to-order pet sold in the United States is named Little Nicky, a nine-week-old kitten delivered to a Texas woman saddened by the loss of a cat she had owned for 17 years.

MOSCOW, 4:29 p.m. Dec. 23 (AP)
Russian cargo ship blasts off for international space station carrying badly needed supplies: A Russian cargo ship blasted off early Friday carrying badly needed food and equipment for the international space station, where supplies for the American and Russian crew have been dwindling rapidly.

LOS ANGELES, 12:42 p.m. Dec. 23 (AP)
Asteroid gets initial elevated risk rating, but impact unlikely: A recently discovered asteroid that crosses Earth's orbit has been given a higher impact hazard rating than any other seen so far, but scientists say it is likely the risk will be eliminated as further observations refine projections of its orbit.

Dec. 22 (UNION-TRIBUNE)
New calendar would lock in day and date: This year, Christmas falls on a Saturday. Next year, it will fall on Sunday, and in 2006, Dec. 25 is a Monday.

SAN FRANCISCO, 2:14 p.m. Dec. 22 (AP)
California company sells cloned cat, generating ethics debate: The first cloned-to-order pet sold in the United States is named Little Nicky, an eight-week-old kitten delivered to a Texas woman saddened by the loss of a cat she had owned for 17 years.

WASHINGTON, 3:17 p.m. Dec. 22 (AP)
New system seeks to save crashing airplanes with parachute: Canadian rancher Albert Kolk's small plane banked uncontrollably in darkness over the Monashee mountains, then began spiraling toward earth. "Seat belts!" he barked to his teenage grandson and two young friends. Then he reached for a red lever in the cockpit.

WASHINGTON, 9:17 a.m. Dec. 22 (REUTERS)
Boeing heavy rocket launches, orbit short of goal: Boeing Co. said Wednesday it had successfully launched its Delta IV heavy-lift rocket for the first time, but a demonstration satellite was placed at a lower orbit than planned.

Dec. 22 (UNION-TRIBUNE)
All five naked-eye planets assume a stellar formation: My very energetic mother just served us nine pizzas. "So what?" you might ask. Well, in third grade I learned that this phrase forms a mnemonic device that helps us remember the correct order of the planets from the sun.

GARDNERVILLE, Nev., 8:50 a.m. Dec. 20 (AP)
Washoe Tribe reaps benefits of solar energy: The Washoe Tribe of Nevada and California is reaping big benefits from solar energy. Since September, solar panels installed on a tribal office in Gardnerville has been absorbing energy and sending it into Sierra Pacific Power Co.'s grid.

Dec. 19 (UNION-TRIBUNE)
How Prop. 71 came to life: Two years ago last weekend, a determined state legislator met with a group of scientists to talk about an idea eavesdroppers might have thought was far-fetched.

PUNTA ARENAS, Chile, 9:59 a.m. Dec. 18 (AP)
The 'hole' pulls back, but 'red days' and danger linger on: The worst of the ozone hole has pulled back once more to Antarctica this southern spring, leaving behind a shadow of uncertainty for the people living at the bottom of the Americas.

Dec. 15 (UNION-TRIBUNE)
UCSD pair contributes to chicken's DNA map: Pavel Pevzner likes to talk about human evolution in terms of the view you can get from a tall building.

BUENOS AIRES, Argentina, 10:48 a.m. Dec. 18 (AP)
As U.S. resists, crack opens in door to new talks on global warming: Long nights of backroom wrangling and a last-minute tangle produced a deal Saturday that opens a small door to international talks about what comes "beyond Kyoto" as the world grapples with the threat of global warming.

Dec. 17 (UNION-TRIBUNE)
Stem cell panel faces misconceptions: Rodney Stobbe of Chula Vista will try nearly anything to stop the tremors in his left hand and lessen the horrible symptoms that Parkinson's disease inflicts on his body.

Dec. 17 (UNION-TRIBUNE)
Inaugural meeting will be short after citizen's complaint: The inaugural meeting of the committee charged with doling out $3 billion in taxpayer money for stem cell research will be shorter than planned, thanks to a citizen's complaint that it violates the state's open-meetings law.

SEATTLE, 1:24 p.m. Dec. 16 (AP)
On second look, feds give 'threatened' listing to San Juan orcas: The federal fisheries agency on Thursday proposed giving Endangered Species Act protection to a struggling community of killer whales that spends much of the year near Washington's San Juan Islands.

Dec. 14 (UNION-TRIBUNE)
Stem cell committee at 22; five more to go: A committee that will oversee $3 billion in funding for stem cell research grew from 11 members to 22 yesterday.

Dec. 15 (UNION-TRIBUNE)
Hurry, these clouds will dissipate shortly: Here at Weather Watch, we have always avoided making product pitches. Open that can of worms, and before we know it, every huckster of every remotely weather-related knickknack in the hemisphere will want us to put our invaluable seal of approval on their item.