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Composition of Asteroid Itokawa
The Hayabusa craft heads toward the asteroid Itokawa
This asteroid ingredient list, published in Science, comes courtesy of Hayabusa, the spacecraft launched in 2003 by the Japanese Aerospace Exploration Agency (JAXA). The mission of Hayabusa is to bring back first-ever samples from an asteroid to better understand their role as building blocks of the solar system. Itokawa, an elongated rocky object nearly as long as five football fields, circles the sun more than 321 million miles away from Earth. Along with a few hundred known asteroids, Itokawa's orbit is close to Earth's orbit and was discovered by the Lincoln Near-Earth Asteroid (LINEAR) program, which detects near-Earth asteroids and provides advance warning if any are bound for Earth. Itokawa doesn't currently pose such a threat, but its close proximity made it a tempting scientific target. A near-infrared spectrometer aboard Hayabusa helped identify Itokawa's mineralogy, mostly a mixture of the rock-forming minerals olivine and pryroxene, and possibly some plagioclase and metallic iron. But to truly understand what they had, the team turned to Takahiro Hiroi, a Brown University researcher who is expert in determining the composition of asteroids and meteorites, bits of asteroids that have fallen to Earth......... Posted by: Brooke Permalink Source Taking a controlling interest in chips
Robert Gu is a recovering Alzheimer's patient. The world that he remembers was much as we know it today. Now, as he regains his faculties through a cure developed during the years of his near-fatal decline, he discovers that the world has changed and so has his place in it. He was a world-renowned poet. Now he is seventy-five years old, though by a medical miracle he looks much younger, and he's starting over, for the first time unsure of his poetic gifts. Living with his son's family, he has no choice but to learn how to cope with a new information age in which the virtual and the real are a seamless continuum, layers of reality built on digital views seen by a single person or millions, depending on your choice. But the consensus reality of the digital world is available only if, like his thirteen-year-old granddaughter Miri, you know how to wear your wireless access--through nodes designed into "smart clothes--and to see the digital context--through "smart contact lenses......... Posted by: Brooke Permalink Source The Hooked Galaxy
ESO PR Photo 22/06.
The Hooked Galaxy and its Companion. MCG-01-39-003 (bottom right) is a peculiar spiral galaxy, with a telephone number name, that presents a hook at one side, most probably due to the interaction with its neighbour, the spiral galaxy NGC 5917 (upper right). In fact, further enhancement of the image reveals that matter is pulled off MCG-01-39-003 by NGC 5917. Both these galaxies are located at similar distances, about 87 million light-years away, towards the constellation of Libra (The Balance). NGC 5917 (also known as Arp 254 and MCG-01-39-002) is about 750 times fainter than can be seen by the unaided eye and is about 40,000 light-years across. It was discovered in 1835 by William Herschel, who strangely enough, seems to have missed its hooked companion, only 2.5 times fainter. As seen at the bottom left of this exceptional VLT image, a still fainter and nameless, but intricately beautiful, barred spiral galaxy looks from a distance the entangled pair, while a number of 'island universes' perform a cosmic dance in the background......... Posted by: Brooke Permalink Source Tracking Earth's Wobbles
Earth's irregular, shorter term wobbles, lasting a week or so, have been more difficult to study, partly because these motions are commonly masked by those of more prominent wobbles. Now, researchers in Belgium and France have taken advantage of a quirk in the pattern of large-scale motions and the advent of the Global Positioning System (GPS) to pin down short-term wobbles that occurred from November 2005 through February 2006. During this period, the Chandler wobble and the annual wobble essentially cancelled each other out, an event that occurs every 6.4 years, allowing the scientists to focus on the short-period wobbles. Over these three and a half months, the pole position traced small loops, ranging in size from that of a sheet of A4 [8-1/2x11 inch] paper down to that of a cell phone, and it remained within a one meter [yard] square during these four months......... Posted by: Tyler Permalink Source Saturnian Moon Ballet
Many denizens of the Saturn system wear a uniformly gray mantle of darkened ice, but not so for these two most fascinating of moons. The brightest body in the Solar System, Enceladus, is contrasted here against Titan's smoggy golden murk.
In addition to their drama and visual interest, researchers use these movies to refine their understanding of the orbits of Saturn's moons. Engineers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., use the same images, and the orbital positions of the moons, to help them navigate the Cassini spacecraft, which is nearing the halfway mark of its four-year tour. Pictures capturing several moons in one frame are often strikingly beautiful, particularly when deliberately imaged in red, green and blue spectral filters, which allow researchers to create a color photo. One recent color image shows two of Saturn's most fascinating moons, icy-white Enceladus and orange, haze-enshrouded Titan. Ironically, what these two moons hold in common gives rise to their starkly contrasting colors. Both bodies are, to varying degrees, geologically active. For Enceladus, its southern polar vents emit a spray of icy particles that coats the small moon, giving it a clean, white veneer. On Titan, as-yet-undefined processes are supplying the atmosphere with methane and other chemicals that are broken down by sunlight, creating the thick yellow-orange haze that suffuses the atmosphere and, over geologic time, falls and coats the surface......... Posted by: Brooke Permalink Source Asteroid Probe Offers New Views
Hayabusa, Japanese for "falcon," achieved a close encounter with asteroid 25143 Itokawa last November. At 1,640 feet (500 meters) long, the asteroid is a small, rocky, "S-type" usually found in the inner regions of the main asteroid belt (virtual solar system). To some observers Itokawa resembles a lumpy potato. Others see a celestial sea otter with a small "head" and larger "body" (sea otter photo and profile). Hayabusa hovered over the oddly shaped asteroid taking images and readings before achieving a daring touchdown in an attempt to capture the first ever asteroid-surface samples......... Posted by: Brooke Permalink Source Astronomers Planning Close-ups Of Mars
Even the most dogged workhorses, however, have limitations. In their entire time on the planet, the slow-moving rovers have traversed less than 10 square miles, and their sensors cannot collect data more than a few feet above the ground. To survey areas of the planet that remain unknown, researchers affiliated with the privately financed German Mars Society in Munich are proposing a different kind of explorer: a vehicle inspired more by dirigibles like the Hindenburg than by land-rover predecessors. Projected to reach Mars in 2009, the balloon craft, named Archimedes, would hover much closer to the planet's surface than a satellite, snapping crisp, full-color images similar to those that an Earth photographer might take from a helicopter......... Posted by: Brooke Permalink Source NASA Gives Green Light For Discovery Launch
Image above: Amid the glow of lights from the fixed and rotating service structures, Space Shuttle Discovery rests on the hardstand of Launch Pad 39B at NASA's Kennedy Space Center. Photo credit: NASA/Ken Thornsley
The decision was announced after a lengthy Flight Readiness Review, a traditional meeting in which top NASA managers and engineers set launch dates, determine whether the shuttle's complex array of equipment, support systems and procedures are ready for flight and assess any risks associated with the mission. "We had two full days of an intensive Flight Readiness Review," said Administrator Michael Griffin. "It was spirited and one of the most open, yet non-adversarial meetings I've seen since returning to NASA". + Read Press Release. William Gerstenmaier, Associate Administrator for Space Operations said "It was a tremendously good review. We were really careful in this. We reviewed everything we could and we think we are ready to go and fly". "The ice frost ramps were one of the most vigorously discussed items. This [foam loss], is what we expect to see in flight. So when we get this data down, you should not be surprised," continued Gerstenmaier. The ice/frost ramps are structures made of insulation foam that cover 34 brackets on the outside of the shuttle's external fuel tank. The ramps have been cited as a potential source of foam loss, which could cause damage to the shuttle. The Flight Readiness Review board decided the current design does not pose sufficient risk to delay the upcoming mission while design improvements for later flights are under way......... Posted by: Brooke Permalink Source Most-detailed Data Yet About Atmospheric Particles
CALIPSO, the fourth satellite in the so-called "A-Train" constellation, follows just a few seconds behind Cloudsat, the satellite it was launched with on April 28. The group of six climate research satellites crosses the equator from north to south at 1:30 p.m. local time on each orbit.
For University of Washington atmospheric researchers Robert Charlson and Theodore Anderson, co-researchers on the CALIPSO satellite's science team, there are two key parts to the research: determining the effects of aerosols on climate in cloudy skies and in clear skies. "Much of the Earth is covered by broken clouds. If you look down at any big patch of clouds, often you will see that it is really made up of broken clouds," said Charlson, a UW atmospheric sciences professor. "That suggests that there could be an intermediate state between clear and cloudy conditions that has a considerable effect on climate, and it appears to be very sensitive to changes in aerosol levels." Aerosols are tiny particles suspended in the air, such as bits of dusty ash from volcanoes, smoke and haze from combustion, soil dust from desert storms and salt from evaporating sea spray. They float in the atmosphere, absorbing some sunlight and reflecting some back into space, but no one knows just how much effect they have globally. Charlson and Anderson say that remains one of the biggest unanswered questions about human-induced climate change......... Posted by: Brooke Permalink Source Twin Instruments To NASA
There would be no other cargo loaded, no unnecessary stops made, no bumpy roads traveled as the truck headed at a measured pace down to the Kennedy Space Center some 1,400 miles away. But the delicate cargo's ultimate destination is just a bit further - 65 million miles from Earth. The truck was carrying one of two identical instruments designed and built at UNH's Institute for the Study of Earth, Oceans, and Space (EOS) for NASA's Solar TErrestrial RElations Observatory or STEREO mission. Over the last six years and after nearly $10 million in NASA funding, UNH scientists, engineers, technicians, machinists, and graduate and undergraduate students have built and tested Flight Models 1 & 2 of the Plasma and SupraThermal Ion Composition (PLASTIC) investigation that will be onboard the twin STEREO spacecraft, which are slated for launch in late July. UNH's total NASA contract for the STEREO mission is $13.2 million, which includes post-launch activities and data analysis......... Posted by: Brooke Permalink Source |
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