AP - NASA is delaying a mission to Mars that already had been over budget and will get even more costly.

AP - NASA has set a May date for its space shuttle mission to fix the Hubble Space Telescope for a final time.

LiveScience.com - A fossil of a toothless flying pterosaur, with a body bigger than some family cars, represents the largest of these extinct reptiles ever to be found and has forced the creation of a new genus, scientists announced today.

AFP - Iran's President Mahmoud Ahmadinejad has for the first time admitted that the fall in world oil prices will affect the economic projects of his government, local media reported on Thursday.

Reuters - Rogue clinics around the world may be exploiting hope and ignorance by offering unproven stem cell therapies, a group of stem cell experts said in a report released on Wednesday.

AP - A conservation group is going to court to force the federal government to consider adding the Pacific walrus to the list of threatened species.

AP - More than 400 years after Danish astronomer Tycho Brahe challenged established wisdom about the heavens by analyzing a strange new light in the sky, scientists say they've finally nailed down just what he saw.

HealthDay - WEDNESDAY, Dec. 3 (HealthDay News) -- Expensive, sham stem cell therapies are being hawked directly to desperate patients over the Internet, experts say.

AP - The amount of U.S. greenhouse gases flowing into the atmosphere, mainly carbon dioxide from burning fossil fuels, increased last year by 1.4 percent after a decline in 2006, the Energy Department reported Wednesday.

AP - What does a teenage brain on Google look like? Do all those hours spent online rewire the circuitry? Could these kids even relate better to emoticons than to real people? These sound like concerns from worried parents. But they're coming from brain scientists.

AP - Kids can keep visiting Billy the elephant at the Los Angeles Zoo — for now.

AP - Consumers should be wary of Web sites from clinics that offer stem cell treatments, says a study that found a lack of firm medical evidence to back up their claims. The Web sites in the study generally portrayed their therapies as safe, effective and ready for routine use, but published research doesn't support that "overoptimistic" picture, the study authors said.

AP - Iran's hard-line president has acknowledged publicly for the first time that his country's economy is taking a severe beating from tumbling oil prices, a damaging admission by a leader whose popularity is eroding ahead of a tough re-election battle next year.

SPACE.com - On Nov. 11, 1572, astronomer Tycho Brahe observed a bright "new star" — now known as a supernova — in the constellation Cassiopeia.