A NASA press release indicates that NASA's Spirit, the first of two Mars Exploration Rovers on the surface within Mars' Gusev crater, has identified carbonate minerals "in the rover's first survey of the site with its infrared sensing instrument, called the miniature thermal emission spectrometer or Mini-TES. Carbonates form in the presence of water, but it's too early to tell whether the amounts detected come from interaction with water vapor in Mars' atmosphere or are evidence of a watery local environment in the past, scientists emphasized."
"We came looking for carbonates. We have them. We're going to chase them," said Dr. Phil Christensen of Arizona State University, Tempe, leader of the Mini-TES team. Previous infrared readings from Mars orbit have revealed a low concentration of carbonates distributed globally. Christensen has interpreted that as the result of dust interaction with atmospheric water. First indications are that the carbonate concentration near Spirit may be higher than the Mars global average.
After the rover drives off its lander platform, infrared measurements it takes as it explores the area may allow scientists to judge whether the water indicated by the nearby carbonates was in the air or in a suspected ancient lake. http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040109a/graph-carb...
Virginia Tech (USA) researchers found that calcium intake among US adolescents has remained constant, if inadequate, since the 1970s and does not appear to be linked to soft drink consumption. Milk consumption among adolescent girls is low, with this group falling far below recommended dietary levels of calcium consumption. So drink some milk!
Conclusion: carbonated soft drink consumption among adolescent girls is modest and does not appear to be linked to decreased calcium intake. The analyses in this paper show that creative effective, efficient, and targeted policies should be considered to help adolescent girls increase calcium intake. Making low-fat milk products, flavored milks, calcium-fortified beverages and foods more attractive and available will help encourage girls to consume more of this important mineral. When adequate calcium intake is not achieved through foods, health professionals should consider recommending calcium supplements.
Scientists at NASA's Johnson Space Center in Houston have shipped pieces of the Genesis polished aluminium collector to researchers at Washington University in St. Louis, marking the first distribution of a Genesis scientific sample from JSC since the science canister arrived there Oct. 4, 2004. The sample, the first to be allocated for Genesis early science analysis, may hold important evidence about the overall composition of the sun.
While much of the solar wind is hydrogen, it is hoped that Genesis captured samples of many elements in the periodic table. An analysis of these elements will help to determine the sun's composition in detail. Several important Genesis science objectives will be investigated as part of the Early Science Return, including studies of noble gas isotopes in bulk solar wind and nitrogen isotopes.
The U.S. Department of Energy's Brookhaven National Laboratory reports that scientists at the US Brookhaven National Laboratory and the IBM T.J. Watson Research Center caused an individual carbon nanotube to emit light for the first time. This may have significance for many of the proposed applications for carbon nanotubes including in electronics and photonics.
The light emission is the result of a process called "electron-hole recombination." By running an electric current through a carbon nanotube - a long, hollow cylindrical molecule that is only one and a half nanometers (a billionth of a meter) in diameter - negatively charged electrons in the nanotube molecule combine with positively charged "holes," which are locations in the molecule where electrons are missing. When an electron fills a hole, it emits a photon - a tiny burst of light.
"We produced infrared light by applying voltages to a specific type of nanotube such that many electrons and holes end up in the nanotube, where they combine. This makes the nanotube the world's smallest electrically-controllable light emitter," said James Misewich, a materials scientist at Brookhaven. "It's an exciting result, and my colleagues and I plan to continue studying the effect to determine the mechanisms behind it. For example, we hope to understand how to make the nanotubes emit other types of light, such as visible light, and how to increase the efficiency of the emission." Carbon nanotubes do not yet have any mainstream practical applications, but researchers are investigating ways to use them in flat-panel displays, such as televisions and computer monitors, or as reinforcements in building materials, due to their exceptional mechanical strength. Misewich also suggested that, if additional research leads to an increased efficiency of nanotube light emission, the nanotubes could possibly be used in lighting applications.
A NASA scientist has discovered sugar and several related organic compounds in two meteorites -- providing the first evidence that another fundamental building block of life on Earth might have come from outer space.
Dr. George Cooper and coworkers from the NASA Ames Research Center found the sugary compounds in two carbon-rich (or carbonaceous) meteorites. Previously, researchers had found inside meteorites other organic, carbon-based compounds that play major roles in life on Earth, such as amino acids and carboxylic acids, but no sugars.
These discoveries add an important new piece to the puzzle of the origins of life on Earth, and supports the notion that seeds of life might be spread far and wide around the cosmos.1
"Finding these compounds greatly adds to our understanding of what organic materials could have been present on Earth before life began," Cooper said. "Sugar chemistry appears to be involved in life as far back as our records go." Recent research using ratios of carbon isotopes have pushed the origin of life on Earth to as far back as 3.8 billion years, he said. (An isotope is one of two or more atoms whose nuclei have the same number of protons but different numbers of neutrons.)
"This discovery shows that it's highly likely organic synthesis critical to life has gone on throughout the universe," said Kenneth A. Souza, acting director of astrobiology and space research at Ames. "Then, on Earth, since the other critical elements were in place, life could blossom."
- 1. Carbonaceous meteorites as a source of sugar-related organic compounds for the early Earth,
, Nature, 12/2001, Volume 414, Issue 6866, p.879 - 883, (2001)
The observation that soot makes global warming "worse" is well covered today. The BBC covers this - largely because it appears that soot is more important for global warming than realised earlier. Dr James Hansen and Larissa Nazarenko, (Goddard Institute for Space Studies, NASA, and Columbia University Earth Institute) suggest that trying to reduce the amount of soot produced would be easier than cutting carbon dioxide and other greenhouse gas emissions. Concentrations of soot are often high over China and India, where coal and organic fuels are used domestically, and over Europe and North America, where the main source is diesel oil.1