Sunlight can be brutal. It wears down even the strongest structures, including rooftops and naval ships, and it
The post Glass paint could keep metal roofs and other structures cool even on sunny days has been published on Technology Org.
Quasars are the light fantastic. These brilliant cores of active galaxies blaze with the radiance of a hundred billion stars compressed into a region of space not much larger than our solar system. Supermassive black holes, with millions or billions of times the mass of our sun, are the only imaginable powerhouse behind these tsunamis of raw energy.
For a simple molecule, ozone (O3) wears many hats. Up in the stratosphere, the ozone layer provides planetary sunscreen, absorbing UV radiation before it can reach the Earth. Between the surface and the stratosphere, ozone’s significance comes from absorbing infrared radiation from the Earth—it’s a greenhouse gas. And down at ground level, ozone's reactivity makes it a harmful enough lung irritant that it’s a part of the daily weather report in some cities.
Ozone is produced in the atmosphere naturally, but it’s also created as a result of air pollution. In particular, nitrogen oxides react with sunlight to let rogue oxygen atoms loose, which can get together with friendly O2 molecules in the lower atmosphere, forming O3. By cutting the emissions of those “ozone precursors,” we can dial back the amount of ozone down here where we breathe. In the western US, emissions of nitrogen oxides were reduced by 21 percent between 2005 and 2010, yet ozone stayed about constant. Part of the answer to that conundrum lies across the Pacific, according to a new study led by Wageningen University’s Willem Verstraeten.
The suggestion that ozone from China is ending up in the US isn’t new, but the researchers turned to data from NASA’s Aura satellite (launched in 2004) to improve past estimates. The satellite data confirmed that nitrogen oxides had declined across the American West, while average ozone hadn’t changed much (some areas saw a slight decrease and some a slight increase). In China, on the other hand, emissions of nitrogen oxides rose about 21 percent between 2005 and 2010, and ozone increased by around seven percent.
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The ALICE experiment at the Large Hadron Collider (LHC) at CERN has made a precise measurement of the difference
The post ALICE precisely compares light nuclei and antinuclei has been published on Technology Org.
The 16th century Portuguese navigator Ferdinand Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two fuzzy cloud-like objects easily visible to southern hemisphere skygazers are known as the Clouds of Magellan, now understood to be satellite galaxies of our much larger, spiral Milky Way galaxy. About 160,000 light-years distant in the constellation Dorado, the Large Magellanic Cloud (LMC) is seen here in a remarkably deep, colorful, image. Spanning about 15,000 light-years or so, it is the most massive of the Milky Way's satellite galaxies and is the home of the closest supernova in modern times, SN 1987A. The prominent patch below center is 30 Doradus, also known as the magnificent Tarantula Nebula, is a giant star-forming region about 1,000 light-years across.The existence of our world is anything but self-evident. The Big Bang created matter and antimatter in equal
The post Record measurements of matter and antimatter has been published on Technology Org.
Up until now, no material has been able to conduct current with no resistance at such high temperatures:
The post Superconductivity: No resistance at record temperatures has been published on Technology Org.
After berthing with the ISS, CALET is to be extracted by robotic arm from the Japanese H-II transfer vehicle (left, with Japanese flag) and installed on the Japanese Experiment Module (right) where it will start its first data-taking (Image: NASA/JAXA)
Five days after it launched from the Tanegashima Space Center on board the HTV-5 Transport Module, operated by the Japan Aerospace Exploration Agency (JAXA), the CALorimetric Electron Telescope (CALET) docked at the International Space Station (ISS). The instrument, now in the check-out phase, is sending its first signals back from the Space Station.
CALET is the space mission lead by JAXA with the participation of the Italian Space Agency (ASI) and NASA. It is a CERN recognized experiment and the second high-energy astroparticle experiment to be installed on the ISS after AMS-02, which is taking data from the remote station since 2011. Designed as a space observatory for long-term observations of cosmic radiation aboard the external platform JEM-EF of the Japanese module (KIBO) on the ISS, CALET aims at identifying electrons, nuclei and gamma-rays coming from space and measure their energies with high-resolution. “One of the main scientific objectives of CALET is to measure the detailed shape of the electron spectrum above 1 TeV,” says Shoji Torii of Waseda University in Tokyo, Principal Investigator (PI) of CALET. “This unexplored region is gaining a growing interest by the scientific community as it might be able to show for the first time the smoking gun of the presence of nearby astronomical source(s) where electrons are accelerated. We know that electrons cannot travel for long distances as they quickly lose their energy. Therefore, they are expected to originate relatively near to Earth – about 1 Kpc.”
CALET will perform accurate measurements of the electron energy spectrum from 1 GeV to 20 TeV. “The high end of the spectrum could be particularly interesting as it could help resolve the controversial interpretation of the electron and positron spectra measured by AMS-02 and could provide a clue on possible signatures of dark matter,” says John Wefel of Louisiana State University, Co-PI of the CALET project and lead of the American team participating in CALET.
CALET could also help explain the deviation from a pure power-law that was recently observed by the AMS-02 collaboration in the energy spectra of light nuclei. “Thanks to its excellent energy resolution and ability to identify cosmic nuclei from hydrogen to iron and above,” says Pier Simone Marrocchesi, Co-PI of the CALET collaboration and head of the Italian team. “CALET will be able to extend the present data to higher energies and measure accurately the curvature of the spectrum and the position of the spectral break-point for individual nuclear species. The calibration of the two calorimetric instruments is the key to control the energy scale and this is why we performed several calibration tests at CERN.”
After berthing with the ISS, CALET will be extracted by a robotic arm from the Japanese H-II transfer vehicle (HTV5) and installed on the JEM-EF where it will start a first data-taking period of 5 years.
