The OH “radical” is a very special and reactive molecule, which is unusual in conventional chemistry because of its reactivity. Using the VIRTIS instrument onboard Venus Express, an international team of astronomers  observed the light emission from the night side of Venus's atmosphere and detected the presence of the OH radical in the spectra. The Venus Express spacecraft has been orbiting Venus for more than two years and has already provided planetologists with a handful of new results .
Just like the Earth, the atmosphere of Venus emits a very weak light caused by various processes occurring in the upper atmosphere. On Earth, this weak emission of light, known as airglow, was discovered in 1868. It is also referred to as nightglow because it can only be seen during the night. In the daytime, it is hidden by the much stronger light because of sunlight scattering. Observing atmospheric airglow is a major tool for inferring the composition and chemistry of the upper atmospheres of planets. For example, in Earth's atmosphere, the airglow from the OH radical, which was detected in 1948, was later found to play an important role in purging the atmosphere of pollutants harmful to the biosphere. Theoretical studies show that the hydroxyl airglow also plays an important role in the chemistry of Mars' atmosphere, but it has not yet been detected.
On Venus, airglow emissions have already been observed coming from nitrogen monoxide (NO) and oxygen dioxide (O2). The VIRTIS team now reports measurements of four airglow emission lines: two from OH at 1.44 and 2.80 microns and two from O2 at 1.27 and 1.58 microns. Figure 1 illustrates these detections. Except for the O2 emission line at 1.27 micron, which has already been observed on Venus, all three of the other emission lines have never been observed before, neither on Venus nor on another planet besides Earth .
These new observations are the most direct information found yet of three key components of Venus's upper atmosphere: hydrogen, hydroxyl, ozone (O3), and possibly perhydroxyl (HO2).
 The team of astronomers includes G. Piccioni, A. Migliorini, V. Cottini (INAF-IASF, Roma, Italy), P. Drossart, S. Erard (LESIA, Observatoire de Paris, CNRS, France), L. Zasova, A. Shakun, N. Ignatiev (IKI, Russia), J-C Gérard (LPAP, Liège, Belgium), F.P. Mills, A. Garcia Munoz (Australian National Univ.), D. Grassi, (INAF-IFSI, Roma, Italy), F.W. Taylor (Oxford Univ., UK), and the VIRTIS-Venus Express Technical Team.
 Visit the Venus Express web site at http://www.esa.int/SPECIALS/Venus_Express/index.html
 While never detected before on another planet besides Earth, hydroxyl is frequently observed in the atmosphere of comets.
Jennifer Martin | alfa
Quantum optics allows us to abandon expensive lasers in spectroscopy
22.11.2017 | Lomonosov Moscow State University
Nano-watch has steady hands
22.11.2017 | University of Vienna
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
22.11.2017 | Business and Finance
22.11.2017 | Physics and Astronomy
22.11.2017 | Physics and Astronomy