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NASA Unlocks The Puzzle Of Global Air Quality
UNH research associate professor and atmospheric chemist Jack Dibb and research project engineer Eric Scheuer are currently on the jetliner among a select group of researchers taking part in NASA's Intercontinental Chemical Transport Experiment, or INTEX-B. This two-phase experiment is aimed at understanding the transport and transformation of gases and aerosols on transcontinental and intercontinental scales and assessing their impact on global air quality and climate. The first phase of INTEX-B kicked off in March when NASA, in collaboration with several other agencies and universities, quantified the outflow and evolution of gases and aerosols from Mexico City, one of the most heavily polluted "megacities" in the world. The current phase of INTEX-B is probing large, polluted air masses flowing off the Asian continent towards North America. The DC-8, in conjunction with a National Science Foundation-National Atmospheric Research Center C-130 research aircraft, is now plying the air above the Pacific Ocean measuring a wide range of pollutants. Because of meteorological conditions, this time of year is the peak outflow of Asian pollution toward the North American continent. Dibb says that already, with just three flights completed, they are seeing "pervasive" pollution throughout the North Pacific......... Posted by: Tyler Permalink Source Spectacular View Of Ongoing Comet Breakup
Amateur and professional astronomers around the world have been tracking the spectacular disintegration of 73P/Schwassmann-Wachmann 3 for years. As it plummets towards a close encounter with the Sun, swinging round the Sun on 7 June and heading away to begin another loop round the Solar System, the comet will pass the Earth on 12 May, at a distance of 11.7 million kilometres, or 30 times the distance between Earth and the Moon. The comet currently comprises a chain of over 33 separate fragments, named alphabetically, and stretching across several degrees on the sky (the Sun and Moon each have an apparent diameter of about 1/2 a degree). Ground-based observers have noted dramatic brightening events associated with some of the fragments indicating that they are continuing to break up and that some may disappear altogether. Hubble caught two of the fragments, B and G, shortly after major outbursts in activity. The resulting images reveal that an amazing process of hierarchical destruction is taking place, in which the larger fragments are continuing to break up into smaller chunks. Several dozen "mini-fragments" are to be found trailing behind each main fragment, probably associated with the ejection of house-sized chunks of surface material that can only be detected in these very high-resolution Hubble images......... Posted by: Brooke Permalink Source Geoinformation from space sharpens population density maps
EO-STAT 'real-world population' distribution of Austria in 3D Credits: GeoVille
GeoVille, an Austrian company specialising in geo-information, and Tele Atlas, the largest manufacturer of road networks worldwide, are providing detailed models of areas based on road network information, statistical population data - supplied by the German-based market research institute GfK - and Earth observation (EO) images from ESA's Envisat, NASA's LANDSAT and the French Space Agency's SPOT satellites. Results are then integrated into Tele Atlas' digital geographic database, MultiNet, and can - among other applications - be used to spot the target groups for geomarketing campaigns. Geomarketing determines consumer profiles as per geographical zones based on market-specific data by using geographical information along with population and economic statistics. Companies can use this information to visualize the geographic location of potential target groups before implementing costly marketing campaigns and to envision future growth on a local or national scale. For instance, this information can be used to strategically choose a heavily-populated area in which to place a business in another country without ever placing a foot in the region......... Posted by: Tyler Permalink Source Hubble's View Of Cigar Galaxy
To celebrate the NASA-ESA Hubble Space Telescope's 16 years of success, the two space agencies are releasing the sharpest wide-angle view ever obtained of Messier 82 (M82), a galaxy remarkable for its webs of shredded clouds and flame-like plumes of glowing hydrogen blasting out from its central regions. Located 12 million light-years away, M82 appears high in the northern spring sky in the direction of the constellation Ursa Major, the Great Bear. It is also called the 'Cigar Galaxy' because of the elongated elliptical shape produced by the tilt of its starry disk relative to our line of sight. As shown in this mosaic image, M82 is a magnificent starburst galaxy. Throughout its central region young stars are being born ten times faster than they are inside in our Milky Way Galaxy. These numerous hot new stars not only emit radiation but also charged particles that form the so-called stellar wind. Stellar winds streaming from these stars combine to form a galactic 'superwind'. The superwind compresses enough gas to trigger the ignition of millions more stars and blasts out towering plumes of hot ionised hydrogen gas, above and below the disk of the galaxy (seen in red in the image). In M82 young stars are crammed into star clusters. These then congregate by the dozen to make the bright patches or 'starburst clumps' seen in the central parts of M82. The individual clusters in the clumps can only be distinguished in the ultra-sharp Hubble images......... Posted by: Brooke Permalink Source The Comet With a Broken Heart
On the night of April 23 to 24, ESO's Very Large Telescope observed fragment B of the comet Schwassmann-Wachmann 3 that had split a few days earlier. To their great surprise, the ESO astronomers discovered that the piece just ejected by fragment B was splitting again! Five other mini-comets are also visible on the image. The comet seems thus doomed to disintegrate but the question remains in how much time. Comet P73/Schwassmann-Wachmann 3 (SW 3) is a body with a very tormented past. This comet revolves around the Sun in about 5.4 years, in a very elongated orbit that brings it from inwards of the Earth's orbit to the neighbourhood of giant planet Jupiter. In 1995, when it was coming 'close' to the Earth, it underwent a dramatic and completely unexpected, thousand-fold brightening. Observations in 1996, with ESO's New Technology Telescope and 3.6-m telescope, at La Silla, showed that this was due to the fact that the comet had split into three distinct pieces. Later, in December 1996, two more fragments were discovered. At the last comeback, in 2001, of these five fragments only three were still seen, the fragments C (the largest one), B and E. No new fragmentations happened during this approach, apparently. Things were different this time, when the comet moved again towards its closest approach to the Sun - and to the Earth. Early in March, seven fragments were observed, the brightest (fragment C) being of magnitude 12, i.e. 250 fainter than what the unaided can see, while fragment B was 10 times fainter still. In the course of March, 6 new fragments were seen......... Posted by: Brooke Permalink Source The Giant Magellan Telescope Group Grows
"The addition of the Australian National University to the GMT consortium is the most recent indication of the momentum that the project is generating," commented Wendy Freedman, chair of the GMT board and the Crawford H. Greenewalt director of the Carnegie Observatories. "We couldn't be more pleased with ANU's participation. We all share a common goal of probing the most important questions in astronomy facing us over the next generation-the mysteries of dark energy, dark matter, and black holes; the birth of stars and planetary systems in our Milky Way; the genesis of galaxies; and much more". "The GMT represents a new epoch for astronomy," stated Richard Meserve, president of the Carnegie Institution. "Now, with a group of nine, the consortium is well on its way to accomplishing its goals," he added......... Posted by: Brooke Permalink Source Young Mars Most Likely To Support Life
The large dark area right of center on the hemisphere view of Mars is Syrtis Major. The map shows the presence of water-bearing clay minerals identified by OMEGA data. Blue indicates small amounts and orange-red indicates large amounts.
This is the finding of an international team of researchers who have created the most comprehensive mineral history of Mars, a history closely linked to the presence of liquid water on the planet. As per the mineral record, created with Mars Express mission data and detailed in Science, Mars would only have been hospitable to life in its infancy. "Starting about 3.5 billion years ago, conditions on Mars became increasingly dry and acidic - not a pleasant place for any form of life, even a microbe," said John Mustard, a Brown University geologist and a primary author of the Science paper. If any living organisms had formed on Mars, that evidence would likely be found in clay-rich rocks and soil north of the Syrtis Major volcanic plateau, in Nili Fossae and in the Marwth Vallis Regions, the team reports. These areas make compelling targets for future lander missions, as per Mustard, a co-investigator on the Mars Express and Mars Reconnaissance Orbiter missions. In the meantime, the Compact Reconnaissance Imaging Spectrometer for Mars, or CRISM, aboard the Mars Reconnaissance Orbiter, will in September begin beaming mineralogical data on these clay-rich regions. The images will be 20 times more precise compared with those captured by Mars Express......... Posted by: Brooke Permalink Source Magellanic Gemstones In The Southern Sky
Hubble has captured the most detailed images to date of the open star clusters NGC 265 and NGC 290 in the Small Magellanic Cloud - two sparkling sets of gemstones in the southern sky. Two new composite images taken with the Advanced Camera for Surveys onboard the NASA/ESA Hubble Space Telescope show a myriad of stars in crystal clear detail. The brilliant open star clusters, NGC 265 and NGC 290, are located about 200,000 light-years away and are roughly 65 light-years across. Star clusters can be held together tightly by gravity, as is the case with densely packed crowds of hundreds of thousands of stars, called globular clusters. Or, they can be more loosely bound, irregularly shaped groupings of up to several thousands of stars, like the open clusters shown in this image. The stars in these open clusters are all relatively young and were born from the same cloud of interstellar gas. Just as old school-friends drift apart after graduation, the stars in an open cluster will only remain together for a limited time and gradually disperse into space, pulled away by the gravitational tugs of other passing clusters and clouds of gas. Most open clusters dissolve within a few hundred million years, whereas the more tightly bound globular clusters can exist for a number of billions of years......... Posted by: Brooke Permalink Source Metop Satellite Shipped To Baikonur
MetOp's arrival at Baikonur ESA PR 14-2006. The first MetOp meteorological satellite arrived yesterday at its launch site, the Baikonur Cosmodrome in Kazakhstan, following shipment from the industrial prime contractor, EADS Astrium in Toulouse, on board an Antonov-124 transport plane. MetOp-A is the first in a series of three EUMETSAT Polar System (EPS) satellites developed by the European Space Agency (ESA) for EUMETSAT, the European Organisation for the Exploitation of Meteorological Satellites. After undergoing a mechanical and environmental test campaign, the spacecraft passed the acceptance review last year and the recent compatibility test between satellite and ground segment cleared the way for shipment of the satellite to Baikonur. This shipment comprises a service module, a payload module and the solar array, including the electrical and mechanical ground support equipment needed for the launch campaign. The mission includes a total of 12 instruments developed in cooperation with French Space Agency, CNES, and the US National Oceanic and Atmospheric Administration (NOAA). MetOp is scheduled for launch on 17 July 2006 at 22.28 Baikonur time (18.28 CEST) with the latest Soyuz ST Fregat launcher operated by Starsem. MetOp is the first polar orbiting satellite dedicated to operational meteorology. The MetOp satellite services have been designed to provide global weather data until 2020. MetOp, which will fly at a height of about 837 km, promises, with its 12 sophisticated instruments, to provide data of unprecedented accuracy, thus improving global weather forecasting and providing enhanced climate monitoring capabilities......... Posted by: Brooke Permalink Source Gamma Radiation From The Cosmos Unlikely to happen
Are you losing sleep at night because you're afraid that all life on Earth will suddenly be annihilated by a massive dose of gamma radiation from the cosmos? Well, now you can rest easy. Some scientists have wondered whether a deadly astronomical event called a gamma ray burst could happen in a galaxy like ours, but a group of astronomers at Ohio State University and their colleagues have determined that such an event would be nearly impossible. Gamma ray bursts (GRBs) are high-energy beams of radiation that shoot out from the north and south magnetic poles of a particular kind of star during a supernova explosion, explained Krzysztof Stanek, associate professor of astronomy at Ohio State. Scientists suspect that if a GRB were to occur near our solar system, and one of the beams were to hit Earth, it could cause mass extinctions all over the planet. The GRB would have to be less than 3,000 light years away to pose a danger, Stanek said. One light year is approximately 6 trillion miles, and our galaxy measures 100,000 light years across. So the event would not only have to occur in our galaxy, but relatively close by, as well. In the new study, which Stanek and his coauthors submitted to the Astrophysical Journal, they found that GRBs tend to occur in small, misshapen galaxies that lack heavy chemical elements (astronomers often refer to all elements other than the very lightest ones -- hydrogen, helium, and lithium -- as metals). Even among metal-poor galaxies, the events are rare -- astronomers only detect a GRB once every few years......... Posted by: Tyler Permalink Source |
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