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| ©Unknown |
| A pit excavated by the strong mandibles of dermestid beetle larvae while searching for soft, fat-soaked bone. |
Science & Technology
Paleontologists have long been perplexed by dinosaur fossils with missing pieces - sets of teeth without a jaw bone, bones that are pitted and grooved, even bones that are half gone. Now a Brigham Young University study identifies a culprit: ancient insects that munched on dinosaur bones.
As Charles Darwin showed nearly 150 years ago, bird beaks are exquisitely adapted to the birds' feeding strategy. A team of MIT mathematicians and engineers has now explained exactly how some shorebirds use their long, thin beaks to defy gravity and transport food into their mouths.
The phalarope, commonly found in western North America, takes advantage of surface interactions between its beak and water droplets to propel bits of food from the tip of its long beak to its mouth, the research team reports in the May 16 issue of Science.
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| ©Rainey Schuler |
| MIT researchers have figured out how the phalarope, a shorebird with a long, narrow beak, transports its food from the tip of its beak to its mouth. Here the bird feeds by pecking at the water surface. |
The phalarope, commonly found in western North America, takes advantage of surface interactions between its beak and water droplets to propel bits of food from the tip of its long beak to its mouth, the research team reports in the May 16 issue of Science.
WASHINGTON - Astronomers are baffled after finding an exotic type of star called a pulsar apparently locked in an elongated orbit around a star much like the sun -- an arrangement defying what had been known about such objects.
The rapidly spinning pulsar -- an extraordinarily dense object created when a massive star exploded as a supernova -- is called J1903+0327 and is located about 21,000 light years from Earth, the astronomers said.
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| ©REUTERS/HO/NASA |
| Reckless pulsars - spinning searchlights in space - might tear themselves apart if they whirled too fast, but ripples in the cosmic fabric first predicted by Albert Einstein may set a celestial speed limit. That limit is still extremely high, about 760 revolutions per second, astronomers said on July 2, 2003. |
The rapidly spinning pulsar -- an extraordinarily dense object created when a massive star exploded as a supernova -- is called J1903+0327 and is located about 21,000 light years from Earth, the astronomers said.
Pulsars are like cosmic lighthouses sending out sweeping beams that blink at us across the galactic expanse. Now scientists have spotted a wacky pulsar that doesn't behave exactly like its fellows: Instead of circling a white dwarf star, this one orbits a sun-like star along an oval path.
All other known pulsars that rotate as quickly as this one seem to have picked up speed by pulling off mass from a companion star that has reached the advanced stage of red giant, when its gaseous layers bloat out prior to the end-stage of life as a very compact, dim, white dwarf.
All other known pulsars that rotate as quickly as this one seem to have picked up speed by pulling off mass from a companion star that has reached the advanced stage of red giant, when its gaseous layers bloat out prior to the end-stage of life as a very compact, dim, white dwarf.
Venus Express has detected the molecule hydroxyl on another planet for the first time. This detection gives scientists an important new tool to unlock the workings of Venus's dense atmosphere.
Hydroxyl, an important but difficult-to-detect molecule, is made up of a hydrogen and oxygen atom each. It has been found in the upper reaches of the Venusian atmosphere, some 100 km above the surface, by Venus Express's Visible and Infrared Thermal Imaging Spectrometer, VIRTIS.
The elusive molecule was detected by turning the spacecraft away from the planet and looking along the faintly visible layer of atmosphere surrounding the planet's disc. The instrument detected the hydroxyl molecules by measuring the amount of infrared light that they give off.
Hydroxyl, an important but difficult-to-detect molecule, is made up of a hydrogen and oxygen atom each. It has been found in the upper reaches of the Venusian atmosphere, some 100 km above the surface, by Venus Express's Visible and Infrared Thermal Imaging Spectrometer, VIRTIS.
The elusive molecule was detected by turning the spacecraft away from the planet and looking along the faintly visible layer of atmosphere surrounding the planet's disc. The instrument detected the hydroxyl molecules by measuring the amount of infrared light that they give off.
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| ©ESA/C. Carreau |
| Hydroxyl, an important but difficult-to-detect molecule, is made up of a hydrogen and oxygen atom each. It has been found in the upper reaches of the Venusian atmosphere, some 100 km above the surface, by Venus Express's Visible and Infrared Thermal Imaging Spectrometer, VIRTIS. |
Phobos, a satellite of Mars, will become a ring around the Red Planet in a few million years, an Indian scientist has calculated.
Bijay Kumar Sharma, an assistant professor at the National Institute of Technology in Bihar, said in a recent paper that contrary to previous expectations, Phobos will not fall into the surface of Mars in 50 million years but will be torn apart by the tidal forces of the planet in about 7 million years.
In his paper entitled "Theoretical formulation of the Phobos, moon of Mars, rate of altitudinal loss," Sharma said that the Moon is moving away from the Earth at a rate of 3.7 cm a year, while Phobos is moving closer to its host at a rate of 18.3 cm a year.
Bijay Kumar Sharma, an assistant professor at the National Institute of Technology in Bihar, said in a recent paper that contrary to previous expectations, Phobos will not fall into the surface of Mars in 50 million years but will be torn apart by the tidal forces of the planet in about 7 million years.
In his paper entitled "Theoretical formulation of the Phobos, moon of Mars, rate of altitudinal loss," Sharma said that the Moon is moving away from the Earth at a rate of 3.7 cm a year, while Phobos is moving closer to its host at a rate of 18.3 cm a year.
Physicists at Penn State have provided a mechanism by which information can be recovered from black holes, those regions of space where gravity is so strong that, according to Einstein's theory of general relativity, not even light can escape. The team's findings pave the way toward ending a decades-long debate sparked by renowned physicist Steven Hawking.
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| ©ESA / V. Beckmann (NASA-GSFC) |
| An artist's depiction of the accretion of a thick ring of dust into a supermassive black hole. The accretion produces jets of gamma rays and X-rays. |
WASHINGTON - A baby supernova, just over a century old, has been found in the middle of our own Milky Way galaxy and provides an unprecedented opportunity to watch a star dying, astronomers said on Wednesday.
The supernova, known as G1.9+0.3, would have made a bright flash when it first exploded 140 years ago but was not seen because dust obscures it, David Green of Britain's University of Cambridge and colleagues reported.
"It's by far the youngest supernova identified in the galaxy," Green told reporters in a telephone briefing.
Green first identified the object in 1985 as a possible supernova, using radio readings from the U.S. National Science Foundation's Very Large Array.
The supernova, known as G1.9+0.3, would have made a bright flash when it first exploded 140 years ago but was not seen because dust obscures it, David Green of Britain's University of Cambridge and colleagues reported.
"It's by far the youngest supernova identified in the galaxy," Green told reporters in a telephone briefing.
Green first identified the object in 1985 as a possible supernova, using radio readings from the U.S. National Science Foundation's Very Large Array.
Washington, D.C.--Curved features on Jupiter's moon Europa may indicate that its poles have wandered by almost 90°, report scientists from the Carnegie Institution, Lunar and Planetary Institute, and University of California, Santa Cruz in the 15 May issue of Nature. Such an extreme shift suggests the existence of an internal liquid ocean beneath the icy crust, which could help build the case for Europa as possible habitat for extraterrestrial life.
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| ©P. Schenk/NASA/LPI |
| Arc-shaped troughs (black and white arrows) extend 100s of kilometers on the surface of Jupiter's moon Europa. These enigmatic features are likely fractures resulting from a shift in Europa's spin axis. Vertical scale bar (right) is 100 km. |
In the book '1421', I contended that the Emperor Zhu Di had sent fleets to the Southern Ocean to determine the precise position of the star Canopus. The Chinese needed this information to establish accurate latitudes and longitudes in the southern hemisphere. (United Kingdom paperback edition, pages 161-3, and diagram 1).
Since the book was published we have received more than 100,000 e-mails and letters and millions of people have visited our website 'www.1421.tv'. These visitors from over 130 countries around the world have brought new evidence. To date the most important has been my underestimation of the scale of the undertaking. Instead of 100 ships, over 1000 set sail (800 arrived at Calicut alone). There were many great voyages - Fleets were continuously at sea from 1403 to 1432 and the scale of the losses was even more horrific - more than 900 ships never returned. This is exemplified in the Southern Oceans. The discovery of Zheng He's records shows that four separate fleets charted the Antarctic not the two I have claimed. Some got further south - deep into the Weddell Sea.
This memo describes a catastrophe which overtook the fleets which had sailed south of New Zealand down to Campbell Island and Auckland Island (pp.206-209 of United Kingdom Paperback edition). A huge comet struck the ocean less than a hundred miles from the fleets, incinerating many ships and hurling the blazing wrecks onto New Zealand South Island and the East coasts of Australia, and across the Pacific and Indian Oceans.
Since the book was published we have received more than 100,000 e-mails and letters and millions of people have visited our website 'www.1421.tv'. These visitors from over 130 countries around the world have brought new evidence. To date the most important has been my underestimation of the scale of the undertaking. Instead of 100 ships, over 1000 set sail (800 arrived at Calicut alone). There were many great voyages - Fleets were continuously at sea from 1403 to 1432 and the scale of the losses was even more horrific - more than 900 ships never returned. This is exemplified in the Southern Oceans. The discovery of Zheng He's records shows that four separate fleets charted the Antarctic not the two I have claimed. Some got further south - deep into the Weddell Sea.
This memo describes a catastrophe which overtook the fleets which had sailed south of New Zealand down to Campbell Island and Auckland Island (pp.206-209 of United Kingdom Paperback edition). A huge comet struck the ocean less than a hundred miles from the fleets, incinerating many ships and hurling the blazing wrecks onto New Zealand South Island and the East coasts of Australia, and across the Pacific and Indian Oceans.
