Mars Express confirms methane in the Martian atmosphereMarch 30, 2004During recent observations from the ESA Mars Express spacecraft in orbit around Mars, methane was detected in its atmosphere. Whilst it is too early to draw any conclusions on its origin, exciting as they may be, scientists are thinking about the next steps to take in order to understand more. From the time of its arrival at Mars, the Mars Express spacecraft started producing stunning results. One of the aims of the mission is analysing in detail the chemical composition of the Martian atmosphere, known to consist of 95% percent carbon dioxide plus 5% of minor constituents. It is also from these minor constituents, which scientists expect to be oxygen, water, carbon monoxide, formaldehyde and methane, that we may get important information on the evolution of the planet and possible implications for the presence of past or present life. The presence of methane has been confirmed thanks to the observations of the Planetary Fourier Spectrometer (PFS) on board Mars Express during the past few weeks. This instrument is able to detect the presence of particular molecules by analysing their "spectral fingerprints" - the specific way each molecule absorbs the sunlight it receives. The measurements confirm so far that the amount of methane is very small - about 10 parts in a thousand million, so its production process is probably small. However, the exciting question "where does this methane come from?" remains. Methane, unless it is continuously produced by a source, only survives in the Martian atmosphere for a few hundreds of years because it quickly oxidises to form water and carbon dioxide, both present in the Martian atmosphere. So, there must be a mechanism that refills the atmosphere with methane. "The first thing to understand is how exactly the methane is distributed in the Martian atmosphere," says Vittorio Formisano, Principal Investigator for the PFS instrument. "Since the methane presence is so small, we need to take more measurements. Only then we will have enough data to make a statistical analysis and understand whether there are regions of the atmosphere where methane is more concentrated". Once this is done, scientists will try to establish a link between the planet-wide distribution of methane and possible atmospheric or surface processes that may produce it. "Based on our experience on Earth, the methane production could be linked to volcanic or hydro-thermal activity on Mars. The High Resolution Stereo camera (HRSC) on Mars Express could help us identify visible activity, if it exists, on the surface of the planet", continues Formisano. Clearly, if it was the case, this would imply a very important consequence, as present volcanic activity had never been detected so far on Mars. Other hypotheses could also be considered. On Earth, methane is a by-product of biological activity, such as fermentation. "If we have to exclude the volcanic hypothesis, we could still consider the possibility of life," concludes Formisano. "In the next few weeks, the PFS and other instruments on-board Mars Express will continue gathering data on the Martian atmosphere, and by then we will be able to draw a more precise picture," says Agustin Chicarro, ESA Mars Express Project Scientist. Thanks to the PFS instrument, scientists are also gathering precious data about isotopes in atmospheric molecules such as water and carbon dioxide - very important to understand how the planet was formed and to add clues on the atmospheric escape. The PFS also gives important hints about water-cloud formation on the top of volcanoes, and shows the presence of active photochemical processes in the atmosphere. European Space Agency (ESA) |
|||||||||||||||||||||
| Related Methane Current Events and Methane News Articles Beyond sunlight: Explorers census 17,650 ocean species between edge of darkness and black abyss Census of Marine Life scientists have inventoried an astonishing abundance, diversity and distribution of deep sea species that have never known sunlight - creatures that somehow manage a living in a frigid black world down to 5,000 meters (~3 miles) below the ocean waves. Energy-saving powder It is currently estimated that natural gas resources will be exhausted in 130 years; however, those reserves where extraction is cost-effective will only flow for another 60 years or so. Health care accounts for 8 percent of US carbon footprint The American health care sector accounts for nearly a tenth of the country's carbon dioxide emissions, according to a first-of-its-kind calculation of health care's carbon footprint. Interactions with aerosols boost warming potential of some gases For decades, climate scientists have worked to identify and measure key substances -- notably greenhouse gases and aerosol particles -- that affect Earth's climate. Report examines hidden costs of energy production and use A new report from the National Research Council examines and, when possible, estimates "hidden" costs of energy production and use -- such as the damage air pollution imposes on human health -- that are not reflected in market prices of coal, oil, other energy sources, or the electricity and gasoline produced from them. Caltech researchers reveal unexpected sources of nitrogen fixation Researchers at the California Institute of Technology (Caltech) have identified an unexpected metabolic ability within a symbiotic community of microorganisms that may help solve a lingering mystery about the world's nitrogen-cycling budget. Arctic land and seas account for up to 25 percent of world's carbon sink In a new study in the journal Ecological Monographs, ecologists estimate that Arctic lands and oceans are responsible for up to 25 percent of the global net sink of atmospheric carbon dioxide. Coal-mining hazard resembles explosive volcanic eruption, study shows Worldwide, thousands of workers die every year from mining accidents, and instantaneous coal outbursts in underground mines are among the major killers. But although scientists have been investigating coal outbursts for more than 150 years, the precise mechanism is still unknown. Mystery Solved: Marine Microbe Is Source of Rare Nutrient A new study of microscopic marine microbes, called phytoplankton, by researchers at Woods Hole Oceanographic Institution (WHOI) and the University of South Carolina has solved a ten-year-old mystery about the source of an essential nutrient in the ocean. Denver to Barcelona: Global cities and greenhouse gas emissions Denver released the largest amount of greenhouse gases (GHG) and Barcelona the smallest amount in a new study documenting how differences in climate, population density and other factors affect GHG emissions in global cities. More Methane Current Events and Methane News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||