The meteorite that wiped out the dinosaurs might have been less than half the size of what previous models predicted.
That's the finding of a new technique being developed to estimate the size of ancient impactors that left little or no remaining physical evidence of themselves after they collided with Earth.
Scientists working on the technique used chemical signatures in seawater and ocean sediments to study the dino-killing impact that occurred at the end of the Cretaceous period, about 65 million years ago.
Science & Technology
Knowing how powerful a hurricane is, before it hits land, can help to save lives or to avoid the enormous costs of an unnecessary evacuation. Some MIT researchers think there may be a better, cheaper way of getting that crucial information.
So far, there's only one surefire way of measuring the strength of a hurricane: Sending airplanes to fly right through the most intense winds and into the eye of the storm, carrying out wind-speed measurements as they go.
That's an expensive approach--the specialized planes used for hurricane monitoring cost about $100 million each, and a single flight costs about $50,000. Monitoring one approaching hurricane can easily require a dozen such flights, and so only storms that are approaching U.S. shores get such monitoring, even though the strongest storms occur in the Pacific basin (where they are known as tropical cyclones).
So far, there's only one surefire way of measuring the strength of a hurricane: Sending airplanes to fly right through the most intense winds and into the eye of the storm, carrying out wind-speed measurements as they go.
That's an expensive approach--the specialized planes used for hurricane monitoring cost about $100 million each, and a single flight costs about $50,000. Monitoring one approaching hurricane can easily require a dozen such flights, and so only storms that are approaching U.S. shores get such monitoring, even though the strongest storms occur in the Pacific basin (where they are known as tropical cyclones).
If a picture is worth a thousand words, creating one can have as much value to the illustrator as to the intended audience. This is the case with "Picturing to Learn," a project in which college students create pencil drawings to explain scientific concepts to a typical high school student. The National Science Foundation (NSF), Division of Undergraduate Education, provides support for this effort.
What sets this project apart is its emphasis on inviting students to draw in order to explain scientific concepts to others. The act of creating pencil drawings calls into play a different kind of thought process that forces students to break down larger concepts into their constitutive pieces.
This helps clarify the underlying science--from Brownian motion (the movement of particles suspended in a liquid or gas and the impact of raising the temperature of the liquid), to chemical bonding, to the quantum behavior of a particle in a box. In the same assignment, students are asked to evaluate their own drawings, which helps them identify and appreciate critical components.
What sets this project apart is its emphasis on inviting students to draw in order to explain scientific concepts to others. The act of creating pencil drawings calls into play a different kind of thought process that forces students to break down larger concepts into their constitutive pieces.
This helps clarify the underlying science--from Brownian motion (the movement of particles suspended in a liquid or gas and the impact of raising the temperature of the liquid), to chemical bonding, to the quantum behavior of a particle in a box. In the same assignment, students are asked to evaluate their own drawings, which helps them identify and appreciate critical components.
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| ©Kara Culligan and Eunji Chung, Harvard University; Lina Garcia, Massachusetts Institute of Technology |
| The act of creating pencil drawings calls into play a different kind of thought process that forces students to break down larger concepts into their constitutive pieces. This helps clarify the underlying science--from chemical bonding, to the quantum behavior of a particle in a box, to Brownian motion (the movement of particles suspended in a liquid or gas and the impact of raising the temperature of the liquid). In the same assignment, students are asked to evaluate their own drawings which helps them identify and appreciate critical components. |
A new stereo view of Phobos, the larger and inner of Mars' two tiny moons, has been captured by a NASA spacecraft orbiting Mars.
The High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter took two images of Phobos 10 minutes apart on March 23. Scientists combined the images for a stereo view.
"Phobos is of great interest because it may be rich in water ice and carbon-rich materials," said Alfred McEwen, HiRISE principal investigator at the Lunar and Planetary Laboratory at the University of Arizona, Tucson.
The High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter took two images of Phobos 10 minutes apart on March 23. Scientists combined the images for a stereo view.
"Phobos is of great interest because it may be rich in water ice and carbon-rich materials," said Alfred McEwen, HiRISE principal investigator at the Lunar and Planetary Laboratory at the University of Arizona, Tucson.
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| ©NASA/JPL-Caltech/University of Arizona |
| The High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter took two images of the larger of Mars' two moons, Phobos, within 10 minutes of each other on March 23, 2008. |
U.S. audio historians have discovered and played back a French inventor's historic 1860 recording of a folk song -- the oldest-known audio recording -- made 17 years before Thomas Edison invented the phonograph.
"It's magic," audio historian David Giovannoni said on Thursday. "It's like a ghost singing to you."
Lasting 10 seconds, the recording is of a person singing "Au clair de la lune, Pierrot repondit" ("By the light of the moon, Pierrot replied") -- part of a French song, according to First Sounds, a group of audio historians, recording engineers, sound archivists and others dedicated to preserving humankind's earliest sound recordings.
"It's magic," audio historian David Giovannoni said on Thursday. "It's like a ghost singing to you."
Lasting 10 seconds, the recording is of a person singing "Au clair de la lune, Pierrot repondit" ("By the light of the moon, Pierrot replied") -- part of a French song, according to First Sounds, a group of audio historians, recording engineers, sound archivists and others dedicated to preserving humankind's earliest sound recordings.
A former warehouseman from Longridge has beaten off competition from hundreds of academic researchers from across the United Kingdom and beyond to win a top prize at the 2008 National Astronomy Meeting.
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| ©Unknown |
| Winner: Jaz Pearson |
An international team of astronomers has discovered the coldest brown dwarf star ever observed. This finding, to be published in Astronomy & Astrophysics, is a new step toward filling the gap between stars and planets.
An international team [1] led by French and Canadian astronomers has just discovered the coldest brown dwarf ever observed. Their results will soon be published in Astronomy & Astrophysics. This new finding was made possible by the performance of telescopes worldwide [2]: Canada France Hawaii Telescope (CFHT) and Gemini North Telescope, both located in Hawaii, and the ESO/NTT located in Chile.
An international team [1] led by French and Canadian astronomers has just discovered the coldest brown dwarf ever observed. Their results will soon be published in Astronomy & Astrophysics. This new finding was made possible by the performance of telescopes worldwide [2]: Canada France Hawaii Telescope (CFHT) and Gemini North Telescope, both located in Hawaii, and the ESO/NTT located in Chile.
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| ©Astronomy & Astrophysics |
| Picture of the brown dwarf CFBDS0059 (small red dot on the top of the picture) and its near-infrared spectrum (lowest curve) illustrating the presence of ammonia. |
Spanish and UCL (University College London) scientists have discovered a possible terrestrial-type planet orbiting a star in the constellation of Leo. The new planet, which lies at a distance of 30 light years from the Earth, has a mass five times that of our planet but is the smallest found to date. One full day on the new planet would be equivalent to three weeks on Earth.
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| ©NASA |
| This artist's concept shows a Neptune-sized extrasolar planet circling the star Gliese 436. New simulations show that another exoplanet, possible terrestrial-type, may also be orbiting the star. |
The brightest light on Earth now shines in a laboratory in Texas, one which will enable scientists to create a tabletop star. The $14m Texas Petawatt laser reached greater than one petawatt - one thousand million million watts - of laser power in the past few days, making it the highest powered laser in the world, says Prof Todd Ditmire, a physicist at The University of Texas at Austin.
Every year, the American Institute of Aeronautics and Astronautics awards prizes for the best papers presented at its annual conference. Last year's winner in the nuclear and future flight category went to a paper calling for experimental tests of an astonishing new type of engine. According to the paper, this hyperdrive motor would propel a craft through another dimension at enormous speeds. It could leave Earth at lunchtime and get to the moon in time for dinner. There's just one catch: the idea relies on an obscure and largely unrecognised kind of physics. Can they possibly be serious?
Comment: Sure, they can, but are they? In their paper "Future space propulsion based on Heim's field theory" W. Dröscher and J. Häuser write: And then, further: In other words: the Authors do not understand Heim's theory, but they hope that someone will ;-)
Jack Sarfatti quotes Nobel Prize winner, physicist G. t'Hooft: To which Ark replies:
[Ark] [Sarfatti replies:] And then he continues, writing to Ark:
[Sarfatti] Indeed it looks like a ball game ...;-)