A newly discovered batch of well-preserved dinosaur bones, petrified trees and even freshwater clams in southeastern Utah could provide new clues about life in the region some 150 million years ago. The Bureau of Land Management announced the find Monday, calling the quarry near Hanksville "a major dinosaur fossil discovery."
An excavation revealed at least four sauropods, which are long-necked, long-tailed planteating dinosaurs, and two carnivorous ones, according to the bureau. It may have also uncovered an herbivorous stegosaurus. Animal burrows and petrified tree trunks 6 feet in diameter were found nearby. The site doesn't contain any new species but offers scientists the chance to learn more about the ecology of that time, said Scott Foss, a BLM paleontologist.
The fossilized dinosaurs are from the same late Jurassic period as those at Dinosaur National Monument, which straddles the Utah/Colorado state line, and the Cleveland-Lloyd quarry near Price. It could be a decade or so before the full importance of the Hanksville quarry is known, Foss said. "It does have the potential to match the other major quarries in Utah," he said.
The site, roughly 50 yards wide by 200 yards long, was excavated by a team from the Burpee Museum of Natural History in Rockford, Illinois. Museum officials visited the site for about a week last summer and returned this year for a three week excavation. The area has long been known to locals and BLM officials as a dinosaur haven. But no one knew of the site's magnitude until excavation began.
The bones were found in a sandstone channel of an ancient river. "The preservation of these dinosaurs is excellent," Foss said.
The mix of dinosaurs, trees and other species in the area may help scientists piece together what life was like 145 million years to 150 million years ago, including details about the ancient climate, Foss said. BLM plans to close the site to conduct an environmental assessment for continued work in the area. The agency isn't disclosing the exact location of the find because of security concerns.
Tuesday, June 17, 2008
Earthlike Planets Much More Common Than Previously Thought?
Astronomers find batch of SuperEarths
European researchers said on Monday they discovered a batch of three "SuperEarths" orbiting a nearby star, and two other solar systems with small planets as well. They said their findings, presented at a conference in France, suggest that Earth-like planets may be very common.
"Does every single star harbor planets and, if yes, how many?" asked Michel Mayor of Switzerland's Geneva Observatory. "We may not yet know the answer but we are making huge progress towards it," Mayor said in a statement.
The trio of planets orbit a star slightly less massive than our Sun, 42 light-years away towards the southern Doradus and Pictor constellations. A light-year is the distance light can travel in one year at a speed of 186,000 miles a second, or about 6 trillion miles. The planets are bigger than Earth, one is 4.2 times the mass, one is 6.7 times and the third is 9.4 times.
They orbit their star at extremely rapid speeds, one whizzing around in just four days, compared with Earth's 365 days, one taking 10 days and the slowest taking 20 days. Mayor and colleagues used the High Accuracy Radial velocity Planet Searcher or HARPS, a telescope at La Silla observatory in Chile , to find the planets. More than 270 so-called exoplanets have been found. Most are giants, resembling Jupiter or Saturn. Smaller planets closer to the size of Earth are far more difficult to spot. None can be imaged directly at such distances but can be spotted indirectly using radio waves or, in the case of HARPS, spectrographic measurements. As a planet orbits, it makes the star wobble very slightly , and this can be measured.
"With the advent of much more precise instruments such as the HARPS spectrograph ... we can now discover smaller planets, with masses between 2 and 10 times the Earth's mass," said Stephane Udry, who also worked on the study.
The team also said they found a planet 7.5 times the mass of Earth orbiting the star HD 181433 in 9.5 days. This star also has a Jupiter-like planet that orbits every three years. Another solar system has a planet 22 times the mass of Earth, orbiting every four days, and a Saturn-like planet with a 3 yr period.
"Clearly these planets are only the tip of the iceberg," said Mayor. "The analysis of all the stars studied with HARPS shows that about one third of all solar-like stars have either SuperEarth or Neptune-like planets with orbital periods shorter than 50 days."
European researchers said on Monday they discovered a batch of three "SuperEarths" orbiting a nearby star, and two other solar systems with small planets as well. They said their findings, presented at a conference in France, suggest that Earth-like planets may be very common.
"Does every single star harbor planets and, if yes, how many?" asked Michel Mayor of Switzerland's Geneva Observatory. "We may not yet know the answer but we are making huge progress towards it," Mayor said in a statement.
The trio of planets orbit a star slightly less massive than our Sun, 42 light-years away towards the southern Doradus and Pictor constellations. A light-year is the distance light can travel in one year at a speed of 186,000 miles a second, or about 6 trillion miles. The planets are bigger than Earth, one is 4.2 times the mass, one is 6.7 times and the third is 9.4 times.
They orbit their star at extremely rapid speeds, one whizzing around in just four days, compared with Earth's 365 days, one taking 10 days and the slowest taking 20 days. Mayor and colleagues used the High Accuracy Radial velocity Planet Searcher or HARPS, a telescope at La Silla observatory in Chile , to find the planets. More than 270 so-called exoplanets have been found. Most are giants, resembling Jupiter or Saturn. Smaller planets closer to the size of Earth are far more difficult to spot. None can be imaged directly at such distances but can be spotted indirectly using radio waves or, in the case of HARPS, spectrographic measurements. As a planet orbits, it makes the star wobble very slightly , and this can be measured.
"With the advent of much more precise instruments such as the HARPS spectrograph ... we can now discover smaller planets, with masses between 2 and 10 times the Earth's mass," said Stephane Udry, who also worked on the study.
The team also said they found a planet 7.5 times the mass of Earth orbiting the star HD 181433 in 9.5 days. This star also has a Jupiter-like planet that orbits every three years. Another solar system has a planet 22 times the mass of Earth, orbiting every four days, and a Saturn-like planet with a 3 yr period.
"Clearly these planets are only the tip of the iceberg," said Mayor. "The analysis of all the stars studied with HARPS shows that about one third of all solar-like stars have either SuperEarth or Neptune-like planets with orbital periods shorter than 50 days."
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