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SMART-1 on the trail of the Moon's beginnings
Researchers responsible for the D-CIXS instrument on SMART-1 are also announcing that they have detected aluminium, magnesium and silicon. "We have good maps of iron across the lunar surface. Now we can look forward to making maps of the other elements," says Manuel Grande of the University of Wales, Aberystwyth UK, and D-CIXS' Principal Investigator. Knowing how to translate the D-CIXS orbital data into 'ground truth' has been helped by a cosmic coincidence. On 9 August 1976, the Russian spacecraft Luna 24 was launched. On 18 August it touched down in a region of the Moon known as Mare Crisium and returned a sample of the lunar soil to Earth. In January 2005, SMART-1 was high above Mare Crisium when a giant explosion took place on the Sun. Researchers often dread these storms because they can damage spacecraft but, for the researchers responsible for D-CIXS, it was just what they needed. The D-CIXS instrument depends on X-ray emission from the Sun to excite elements on the lunar surface, which then emit X-rays at characteristic wavelengths. D-CIXS collects these X-ray fingerprints and translates them into the abundance of each chemical element found on the surface of the Moon. Grande and colleagues could relate the D-CIXS Mare Crisium results to the laboratory analysis of the Russian lunar samples......... Posted by: Brooke Permalink Source APL-Built Spacecraft Set for Aug 31 Launch
Built and operated for NASA by the Johns Hopkins University Applied Physics Laboratory (APL), in Laurel, Md., the two-year STEREO (Solar TErrestrial RElations Observatory) mission will explore the origin, evolution and interplanetary consequences of coronal mass ejections. These powerful solar eruptions are a major source of the magnetic disruptions on Earth and a key component of space weather, which can greatly affect satellite operations, communications, power systems, and the lives of astronauts in space. "Building and testing two spacecraft simultaneously has been a technical and scheduling challenge, but an effort at which we've been successful," says Ed Reynolds, APL STEREO project manager. "The entire STEREO team is so proud and excited to launch the twin observatories and be part of the first mission to capture coronal mass ejections in 3-D." To capture the sun in 3-D, the twin observatories will fly as mirror images of each other. One of the observatories will be placed ahead of Earth in its orbit around the sun and the other behind. Just as the slight offset between your eyes provides you with depth perception, this placement will allow the STEREO observatories to obtain 3-D images and particle measurements of the sun......... Posted by: Brooke Permalink Source Surprising Telescope Observations
CU-Boulder astrophysicist Jeffrey Linsky said new data gathered by NASA's Far Ultraviolet Spectroscopic Explorer, or FUSE, satellite, shows why deuterium appears to be distributed unevenly in the Milky Way Galaxy. It apparently has been binding to interstellar dust grains, changing from an easily detectable gaseous form to an unobservable solid form, said Linsky, a fellow of JILA, a joint institute of CU-Boulder and the National Institute of Standards and Technology. The FUSE deuterium study, six years in the making, solves a 35-year-old mystery concerning the distribution of deuterium in the Milky Way while posing new questions about how stars and galaxies are made, according to the research team. A paper on the subject by a team of international researchers led by Linsky is being published in the Aug. 20 issue of The Astrophysical Journal. "Since the 1970s, we have been unable to explain why deuterium levels vary all over the place," said Linsky. "The answer we found is as unsettling as it is exciting"......... Posted by: Brooke Permalink Source Hidden Milky Way deuterium found
This form of hydrogen, called deuterium, was created a few minutes after the Big. Bang, but has been slowly destroyed as it is burned in stars and converted to heavier elements. In fact, it now turns out, that destruction has been occurring even more slowly than previously thought. Published in the Aug. 20 issue of the Astrophysical Journal, the FUSE team's new large deuterium survey solves a 35-year-old mystery concerning deuterium's uneven distribution in the Milky Way galaxy even as it poses new questions about how stars and galaxies are made. "For more than three decades, we have struggled to understand and explain the widely varying levels of deuterium," said Warren Moos, principal investigator of NASA's. FUSE mission and a professor in the Henry A. Rowland Department of Physics and Astronomy at the Krieger School of Arts and Sciences at Johns Hopkins. "Though the answer we have found may be unsettling to some, it represents a major step forward in our understanding of chemical evolution"......... Posted by: Brooke Permalink Source Art On The Moon
It was created by Belgian artist Paul Van Hoeydonck and installed by Apollo 15 astronaut David Scott, along with a plaque bearing the names of the 14 astronauts and cosmonauts who died in the service of space exploration......... Posted by: Brooke Permalink Source Electric Dust Storms on Mars
In 1976, the twin Viking landers scooped up Martian soil and added nutrients mixed with water to it. If microscopic life were present, the nutrients would be used up and waste products would be released. Three different experiments involved in this test gave conflicting results. The Labeled Release and the Gas Exchange experiments indicated something active was in the soil, because the nutrients were broken down. However, the Mass Spectrometer experiment did not find any organic matter in the soil. In 1977, Viking scientists suggested that the contradiction could be explained if a very reactive nonorganic substance that imitated the activity of life by breaking down the nutrients was embedded in the soil. Hydrogen peroxide and ozone (O3) were considered possible reactive compounds. While ultraviolet radiation from the sun could produce a certain amount of reactive chemicals in the atmosphere, nobody knew how large amounts of such reactive material could accumulate in the Martian soil. Some scientists at the time thought that dust storms might be electrically active like thunderstorms on Earth, and that these storms might be a source of the new reactive chemistry......... Posted by: Brooke Permalink Source A Summertime Air Quality Exam
NASA's Aura satellite can see several different forms of air pollution worldwide. This image shows high levels of nitrogen dioxide on the U.S. East Coast in 2005. Credit: NASA
But since early July Washington area skies have been put under a unique microscope as researchers from NASA and around the country assembled a powerful array of scientific instruments -- in space and on the ground -- to dissect the region's atmosphere. The result will be not only a better understanding of intense urban air pollution episodes but also a better toolkit to track and probe air pollution worldwide from space. Two years ago NASA launched the third of its major Earth Observing System satellites -- Aura -- carrying a group of instruments designed to take global measurements of air pollution on a daily basis. Aura sensors can detect five of the six air pollutants regulated by the U.S. Environmental Protection Agency. But to make these 400-mile-high readings as accurate as possible, data from the sophisticated Aura instruments need to be in comparison to data from tried-and-true sensors on Earth. NASA is sponsoring just such a "ground-truth" experiment this summer. Howard University Research Campus, Beltsville, Md., is hosting visiting scientists, graduate students and instruments for a six-week-long series of intensive observations. The experiment is also evaluating the next generation of instruments used in daily weather forecasting, as well as tracking one of the strongest greenhouse gases involved in climate change: water vapor, which at increased levels we feel as humidity......... Posted by: Tyler Permalink Source Atlantis Poised at the Pad
The STS-115 crew consists of Commander Brent W. Jett, Jr., Pilot Christopher J. Ferguson and Mission Specialists Heidemarie M. Stefanyshyn-Piper, Joseph R. Tanner, Daniel C. Burbank and Steven G. MacLean, who represents the Canadian Space Agency. During their 11 days in space, the astronauts will install the integrated P3/P4 truss segment with its two large solar arrays that will provide one-fourth of the total power generation capability of the completed station......... Posted by: Brooke Permalink Source Voyager Finds Three Surprises
The surprises come as the hardy, long-lived spacecraft approaches the edge of our solar system, called the heliopause, where the sun's influence ends and the solar wind smashes into the thin gas between the stars. "These are just the most recent of a number of surprises Voyager has revealed in its 28-year journey of discovery. They tell us that the interaction of our sun with the surrounding interstellar matter from other stars is more dynamic and complex than we had imagined, and that there is more yet to be learned as Voyager begins the final leg of its race to the edge of interstellar space," said Dr. Edward Stone, Voyager project scientist at the California Institute of Technology in Pasadena. Voyager 1 is expected to pass beyond the heliopause into interstellar space in eight to 10 years, with Voyager 2 expected to follow about five years later. Voyager 1 has already passed the termination shock, where the million-mile-per-hour solar wind abruptly slows and becomes denser and hotter as it presses against interstellar gas. It was expected the wind beyond the shock would slow to a few hundred thousand miles per hour. But the Voyager researchers were surprised to find that the speed was much less, and at times the wind appeared to be flowing back inward toward the sun......... Posted by: Brooke Permalink Source Granicus And Tinjar Valles
Granicus Valles and Tinjar Valles
The HRSC obtained these images during orbit 1383 at a ground resolution of approximately 23.7 metres per pixel. The images have been rotated 90 degrees counter-clockwise, so that North is to the left. They show the regions of Granicus Valles and Tinjar Valles, lying at approximately 26.8 degree North and 135.7 degree East. The northwest-aligned Granicus Valles and Tinjar Valles are part of the Utopia-Planitia region, an area believed to be covered by a layer of lava that flowed from the northwest flanks of Elysium Mons into the Utopia-Planitia Basin. Today, this once-smooth volcanic plain is incised by channels of variable size and appearance, including Granicus Valles (towards the West) and Tinjar Valles (towards the North). Both channel systems evolve from a single main channel entering the image scene from southeast (upper right), exhibiting an approximate width of 3 km and extending 300 m below the surrounding terrain at maximum. The impressive sinuous lava channel emanates from the mouth of a radial, a circular drainage area, and runs to the Elysium rise trending into a graben, which is terrain dissected by tectonic deformation......... Posted by: Brooke Permalink Source |
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