Monday, January 26, 2009
Wednesday, January 21, 2009
- On Earth, 90 percent of the gas is produced by living beings
The team is not the first to detect methane on Mars, but is the first to associate it to the time when the temperatures go up, the gas plume seems to arise in some areas, when the summer comes and were detected up to 19 tons of this gas in the atmosphere, using spectrometers. These instruments can measure the gases in the atmosphere by analyzing its signature feature in the electromagnetic spectrum.
Until now, there are no known natural processes on the surface of any planet to produce methane. “Therefore, the presence of significant amounts of methane would require the recent release of gas from reservoirs below the surface. But its origin may be biological or not,” the researchers write in Science.
However, it is underground on Mars that water, and perhaps there may be underground microbes that produce methane: on Earth there are millions of years ago.
Wednesday, January 07, 2009
American scientists discovered that the Milky Way is 15% larger in width, 50% more dense and turns at a speed nearly 15% higher than previously thought. These data were presented by researchers from the National Radio Observatory and the Center for Astronomy and Astrophysics Harvard-Smithsonian a meeting of the American Society of Astronomy held in Long Beach, California.
image from NASA
It has more weight and be faster, it also has greater gravitational force and therefore the greater the potential for conflict with neighboring galaxies, like Andromeda, earlier than expected, even though the billions of light years away, warn the researchers.
The fact that scientific observations are made from within the galaxy makes the measurements and study of its structure, which makes it easier for the other galaxies.
Previously, the value of the magnitude of the Milky Way was calculated from indirect measurements, but the radio-telescopes VLBA the National Science Foundation in the United States now can record images with high quality and make direct measurements of distances and movements regardless of other factors such as brightness.
In images captured by radio telescopes, scientists are located in regions of the Milky Way profuse creation of stars in which the gas molecules increase radio broadcasts.
These areas are bright for the brand of radio-telescope, which determines the three-dimensional movements of these regions, which mostly does not follow a circular path as you move the galaxy, but elliptical and a lower speed to those described by other regions .
It was thus possible to calculate the speed at which the Milky Way rotates around its center is about 914,000 kilometers per hour, 15 percent more than the 791,800 miles per hour that were accepted as a measure for decades.
The team of researchers also suggested that the galaxy has four arms of gas and dust in spiral in which stars are formed, not two.
Portuguese version of this article can be found here.
Investigadores da Universidade de Coimbra identificaram seis microalgas com elevada capacidade para produção de biodiesel e que têm a vantagem de ser alimentadas com o dióxido de carbono (CO2) emitido pelas unidades industriais.
Investigadores de la Universidad de Coimbra identificaron seis microalgas con alta capacidad de producción de biodiesel y tienen la ventaja de ser alimentados con dióxido de carbono (CO2) emitido por las unidades industriales