Science, and High Technology News:

NASA engineers and scientists building the James Webb Space Telescope

GREENBELT, Md. - NASA engineers and scientists building the James Webb Space Telescope have created a new telescope technology called "microshutters." Microshutters are tiny doorways the width of a few hairs that will allow the telescope to view the most distant stars and galaxies humans have ever seen. The microshutters will enable scientists to mask unwanted light from foreground objects so the telescope can focus on the faint light of the first stars and galaxies that formed in the universe. Only the Webb Telescope has this technology. The Webb Telescope will launch in the next decade. In December 2006, the microshutters passed crucial environmental testing to demonstrate that they can withstand the rigors of launching and placement in deep space. NASA's Goddard Space Flight Center, Greenbelt, Md., designed, tested and built the instrument technology. The microshutters will work in conjunction with the telescope's Near Infrared Spectrograph that is being built by the European Space Agency. "To build a telescope that can peer farther than the Hubble Space Telescope can, we needed brand new technology," said Murzy Jhabvala, chief engineer of Goddard's Instrument Technology and Systems Division. "We've worked on this design for more than six years, opening and closing the tiny shutters tens of thousands of times to perfect the technology." Each of the 62,000 shutters measures 100 by 200 microns, or roughly the width of three to six human hairs. The shutters are arranged in four identical grids that have a layout of 171 rows by 365 columns. These shutter grids are in front of an eight million-pixel infrared detector that records the light passing through the open shutters. The detector itself represents a technology breakthrough. Astronomers using ground-based telescopes first take a picture of the sky and map all the objects in which they are interested. They then create a mask resembling a sieve to place on the telescope so that only the light from areas of interest can reach the telescope's detectors. In space, the Webb Telescope will have a wide field of view, and its deep, long observation of the sky will contain millions of light sources. Microshutters allow scientists to remotely and systematically block out light that they do not want, allowing the large-format detector to measure infrared spectra optimally. Previously, masks of space telescopes only covered large regions of a field of view at any one time. "The microshutters provide a conduit for faint light to reach the telescope detectors with very little loss," said Harvey Moseley, the Microshutter Principal Investigator at Goddard. "The shutters allow us to perform spectroscopy on up to 100 targets simultaneously. We will be able to see deeper in less time." Each shutter grid array is etched from a single piece of silicon, leaving a sculpture of cavities and doorframes with microscopic hinges and moving doors. The tiny shutters are laced with magnetic cobalt-iron strips. A passing magnet will open all the doors, pulling them down into the cavity. While the doors are opened, engineers can apply a combination of voltages to keep the selected microshutters open. The remainder close when the magnet moves away. The microshutters must perform at a temperature of minus 388 degrees Fahrenheit (40 Kelvin, -233 degrees Celsius), which is the temperature of the Near Infrared Spectrograph. The microshutters are needed for observing distant, faint sources. Hubble's Ultra-Deep Field provides the deepest view of the universe, an image containing tens of thousands of light sources. Some of these light sources are relatively close and some are from an era just after galaxies and stars formed. To go deeper, scientists need to mask the brighter, closer sources and focus only on the most distant. The same microshutter technology also will efficiently reveal faint features in relatively nearby star fields, where scientists will analyze multiple sources at once. "The microshutters are a remarkable engineering feat that will have applications both in space and on the ground, even outside the realm of astronomy in biotechnology, medicine and communications," said Moseley. For diagrams and images of the microshutters, visit: http://www.nasa.gov/vision/universe/starsgalaxies/microshutters.html Mercury - Venus - The Moon - Mars - Jupiter - Saturn - Pluto

Blog / Archive Hosts

The Library of Congress

Coverage: Various Dates Subject(s) Applied Sciences, Engineering & Technology Area Studies Business, Economics & Industry Environmental Studies Government & Politics History, Genealogy & Archives Military Science Science & Technology Subscription Database List Technical Reports and Standards Related Databases Academic Search Premier Factiva Homeland Security Digital Library InfoTrac OneFile ProQuest Databases

T-F 10:30

Selecting Plants

research this site.

M-W 11:30

Aerosols, Chemistry and Climate

Filed under: Aerosols Greenhouse gases Climate Science — gavin @ 12:21 PM August 12, 2008 Everyone can probably agree that the climate system is complex. Not only do the vagaries of weather patterns and ocean currents make it hard to see climate changes, but the variability in what are often termed the Earth System components complicates the picture enormously. These components - specifically aerosols (particulates in the air - dust, soot, sulphates, nitrates, pollen etc.) and atmospheric chemistry (ozone, methane) - are both affected by climate and affect climate, since aerosols and ozone can interact, absorb, reflect or scatter solar and thermal radiation. This makes for a rich research environment, but can befuddle the unwary. I occasionally marvel at the amount of nonsense that is written about climate change in the more excitable parts of the web, and most of the time, I don't bother to comment. But in relation to the issue of aerosols, chemistry and climate, I read yesterday (h/t Atmoz) probably the most boneheaded article that I have seen in ages (and that's saying a lot). The hook for this piece of foolishness were two interesting articles published this week by Ruckstuhl and colleagues and a draft EPA report on the impacts of climate on air quality. First, Ruckstuhl et al found that as aerosols have decreased in Europe over the last few decades (as a result of environmental standards legislation), the amount of solar radiation at the ground has increased while the amount reflected to space has decreased. They hypothesize that this may have helped Europe warm faster in the last few decades than it would have otherwise done. Or equivalently, since the aerosols are anthropogenic, that European temperatures had been subdued due to the cooling effects of the aerosols - and since they are now decreasing, the full effects of the greenhouse gases are starting to be felt. This is just an update to the 'global brightening' story we have touched on before. The EPA report is concerned with the impacts that climate change can have on atmospheric chemistry, and in particular the summertime peaks in urban ground-level ozone which are a well-known and serious health hazard. These are affected by local temperatures, cloudiness, temperature sensitive biogenic emissions and patterns of weather variability. Again, it is a story we have discussed before. But the NewsBusters article succeeded in getting almost every aspect of these stories wrong. How do I correct thee? Let me count the ways. Aerosols are not smog: First they confuse aerosols with photochemical smog. Both are pollutants, but the first is dominated by sulphate emissions from coal burning power plants, the second from ozone precursors such as NOx, volatile organic compounds, and carbon monoxide mainly emitted from vehicles. (Note that ozone is not directly emitted, but is created by chemical reactions from the precursors with the addition of a bit of photolysis - i.e. sunlight-driven chemistry). The effects on climate are very different: ozone is a greenhouse gas, so increases cause a warming, while sulphate aerosols are reflective, and so increases cause a cooling. The air quality issues in the EPA are almost all focused on ozone. Europe is not the Globe: The next error is to equate changes in temperatures in Europe to the globe. While it would be true that if global aerosol levels declined it would lead to increased global warming, aerosol trends in Asia are increasing strongly, even while those in the US and Europe are dropping. The net effect is possibly a slight drop, but the impact on global temperature is as yet unclear. This regionality matters in both the sulphates case and for ozone. The relevant chemistry is sensitive to water vapour and temperature in varying ways as a function of the pollution level. In remote ocean areas, surface ozone will likely decrease as the globe warms for instance (due to increasing water vapour). In polluted environments increased temperatures and larger temperature-sensitive emissions of isoprene cause enhanced ozone levels. Surface ozone is not in the stratosphere: Next, NewsBusters asserts that the ozone story is confusing because of the .. treaty called the Montreal Protocol. This was designed to reduce and eventually eliminate the production and release of a number of substances thought at the time to be depleting ozone. Ummm…. those substances (chiefly chlorofluorocarbons - CFCs) are still thought to be depleting the ozone layer - which is in the stratosphere, some 30km above the ground-level ozone that people shouldn't be breathing. CFCs have no impact on ground-level ozone at all (since their reactive chlorine is only released in the stratosphere). The final inanity: Wouldn't it be fascinating if such efforts [such as the Montreal Protocol] lead to cleaner air around the world which ended up warming the planet, and that additional warmth is now breaking down the very ozone we thought we could save? Every part of this sentence is wrong. The Montreal Protocol had no impact on cleaning the air, it stopped the growth of CFCs which are powerful greenhouse gases (in addition to their role in depleting stratospheric ozone), therefore it slowed global warming, rather than increasing it, and we aren't trying to save ground-level ozone. Had any of this been true it would indeed have been fascinating. What should we make of this? Unfortunately one must conclude that no mistake is too dumb for someone, somewhere to make if they think they can spin it into supporting their anti-science agenda. For them complexity is something to be abused rather than a challenge to be understood, underlining quite clearly (again) the difference between science and propaganda. Share This 33 blog reactions

Institute for the Future Announces First Massively Multiplayer Forecasting Platform Series of Games Tap Wisdom of Crowds to Address Real-World Problems The Institute for the Future (IFTF), an independent non-profit research organization, has launched a new research platform composed of Massively Multiplayer Forecasting Games (MMFGs). MMFGs are collaborative, open-source simulations of imagined future scenarios. Designed to address real world problems by harnessing the wisdom of crowds, IFTF's new MMFG platform launches with multiple games this fall that invite diverse global groups of people to contribute to futures research through games. Unlike predictions markets where answers fall within a finite range of outcomes, the Institute has created MMFGs to gain insight into situations where the outcome is unknown. "People are tired of feeling helpless about their future -- and there's a lot of uncertainty right now. The introduction of this new platform for research and problem solving gives people a sense of agency and control in preparing for their future," said Marina Gorbis, executive director of IFTF. "As a leading force of innovation in forecasting methodologies, we realized that creating a truly open and collaborative environment for people to imagine, plan for, and ultimately built the future could better serve our clients and the community." Each MMFG's backstory is defined by a unique set of "future parameters" culled from the IFTF's forecast research. These future scenarios introduce new technologies, discoveries, and social phenomenon likely to develop in the next 10 to 25 years. Players document their personal reactions to the scenario and are asked to imagine and record how their families, local communities, or their extended social networks might respond to the game scenarios. Encouraged to build Web sites, produce blogs and wikis, upload podcasts and video, players will persuasively record, discuss, and debate the details of how they imagine their own personal futures might play out within the game parameters. In a related press release, IFTF today announced the world's first MMFG -- Superstruct ( http://www.superstructgame.org). Set in 2019, Superstruct asks players to imagine and help find solutions to five "super-threats" looming over the population -- including global food shortages, crippling pandemics, super-hackers derailing public infrastructure, mass homelessness and a global fuel war. Developed by IFTF researchers Jane McGonigal, Kathi Vian, and Jamais Casico, Superstruct aims to harness the strategic thinking and creativity of its players to find plausible solutions to potential real-life problems. "Massively multiplayer forecasting games is not just a new tool for forecasting, but also a continuation of IFTF's efforts to make forecasting more public, more inclusive, and more experiential," says Howard Rheingold, social media expert and author of Smart Mobs. "A forecasting game is a kind of simulation, a kind of scenario, a kind of teleconference, a kind of artifact from the future -- and more -- that enlists the participants as "first-person forecasters." IFTF will launch three additional forecasting games this year: a game in partnership with United Cerebral Palsy simulating a future reality of caring, a game around earthquake simulation in collaboration with the Art Center College of Design's Design Matters program, and finally, "X2" which will convene a wide variety of distinguished participants from the worlds of science and technology to contribute to the collective knowledge of the future. About the Institute for the Future The Institute for the Future (IFTF) is an independent, nonprofit research group with 40 years of forecasting experience. IFTF focuses on identifying emerging trends and discontinuities that will transform global society and the global marketplace. We provide insights into business strategy, design process, innovation, and social dilemmas. Our research generates the foresight needed to create insights that lead to action. Our research spans a broad territory of deeply transformative trends, from health and health care to technology, the workplace, and human identity. The Institute for the Future is located in Palo Alto, CA. SOURCE Institute for the Future http://www.superstructgame.org PALO ALTO, Calif., Sept 23, 2008 /PRNewswire via COMTEX/

Add your content here