Meteors

A massive bombardment of meteorites billions of years ago could have brought in enough water and carbon dioxide to jump-start the chemistry that let the Earth develop into the garden spot of our solar system. By studying meteorites and other evidence from this bombardment, a team of researchers at Imperial College in England has calculated that the meteorites could have carried in as much as 10 billion tons of water vapor and carbon dioxide to the young Earth every year for millions of years.

From the Hollywood Hills to the Nevada state line, people reported seeing a fireball streaking across the sky and appearing to fall toward the San Bernardino Mountains on Tuesday morning. But explanations of the mysterious object were scarce. San Bernardino County Fire Dispatch reported receiving dozens of calls related to a fireball moving at high speed in the northwest sky around 10:40 a.m. "We got quite a few reports.

The pilot of a Chilean jetliner spotted flaming objects falling near the plane as it headed for a landing in New Zealand, airline officials said. U.S. experts said the objects were probably meteors burning up in the atmosphere. They doubted Australian media reports that the objects could be pieces of a falling Russian spacecraft, saying the space junk had fallen at a different time.

A rock the size of three football fields may have crashed into the California landscape more than 35 million years ago, creating a 3.4-mile-wide crater west of Stockton, San Diego State University researchers reported this month at the Lunar and Planetary Science Conference in Houston. The impact would have created a 1,500-megaton explosion.

The annual Perseid meteor shower will reach its peak Sunday night, with the most activity between midnight and dawn. The combination of a moonless night and a peak that favors North America should make for excellent viewing, experts said. The meteors will appear in all parts of the sky, but experts suggest looking toward the darkest areas. The shower will continue for two more weeks.

A bright meteor streaked across Colorado and Utah early Friday, prompting a rash of calls to authorities. "It came in from the east, over the plains, and was seen to disappear over the mountains to the west," said Chris Peterson, a meteor researcher with the Denver Museum of Nature and Science. Dispatchers in Utah County, south of Salt Lake City, also received reports of the object.

The fireball that streaked across the sky and alarmed numerous Texas residents was likely just a big meteor and not wreckage from colliding satellites, experts said. Federal Aviation Administration spokesman Roland Herwig said the fireball seen across a wide stretch of the state Sunday morning probably was a natural phenomenon and not debris from last week's collision between an Iridium communications satellite and a Russian military space vehicle. Preston Starr, observatory manager at the University of North Texas, said it was probably a meteor about the size of a pickup with the consistency of a chunk of concrete.

Researchers have long wondered why there is not more melted rock at Arizona's Barringer Meteorite Crater between Flagstaff and Winslow. At an impact speed of 34,000 to 44,000 mph, the massive space rock should have melted substantial quantities of the white Coconino geological formation. One possible explanation has been that the meteor contained large amounts of water, which would have lessened the force of the impact that created the 570-foot-deep, 4,100-foot-wide crater.

Dozens of residents in the Pacific Northwest reported seeing a bright streak of light flashing across the sky, startling witnesses from southern Oregon to the Seattle area, according to officials. Scientists said the flaming object was probably a meteor, and that it probably disintegrated before any fragments fell into the Pacific Ocean. Michael O'Connor, a spokesman for the Federal Aviation Administration's regional office in Renton, Wash.

A nighttime meteor shower sparked a flurry of frantic phone calls to police departments across New England from people who saw bright lights moving in the sky, a spokeswoman for the Federal Aviation Administration said. The meteor shower was seen as far north as Portland, Maine, and as far south as Long Island. Some witnesses apparently thought the meteor shower might be a plane crashing, the FAA's Holly Baker said.