China operates world's biggest radio telescope to discover 'laws of universe'

World's largest radio telescope has become operational in southwestern China, with officials in Beijing saying that the project will help scientists search for alien life.

Since the early 1930s, when the first primitive radio telescopes began operating in an attempt to hunt for alien radio signals, astronomers have been busy sifting through the data collected from the immensity of the space to detect the faintest radio signals transmitted from a supposed alien civilization and to help the mankind feel, at last, that its loneliness in the incomprehensible universe is finally eased. The latest of such scientific endeavors is the world’s biggest radio telescope made by Chinese scientists and unveiled on Sunday.

The Aperture Spherical Telescope (FAST), measuring 500 meters in diameter, is erected in a scenic karst valley in Pingtang county, a mountainous area in the southeastern province of Guizhou in China.

The gigantic telescope, which took five years and devoured some $180 million to complete, clearly demonstrates China's growing ambitions in outer space explorations and its vigorous pursuit of global scientific prestige. 

The new Chinese telescope, whose massive dish is made of 4,450 panels, dwarfs the half-a-century old Arecibo Observatory in Puerto Rico as the world's largest single-dish radio telescope, since its sensitivity is twice as the old pal with a reflector as big as 30 football fields. The speed of FAST in surveying is also five to 10 times more than that of the Arecibo Observatory.

The 500-meter Aperture Spherical Telescope (FAST) is seen at the final stage of construction, in the mountains in Pingtang county, Guizhou province, China. (Photo by Reuters)

“The ultimate goal of FAST is to discover the laws of the development of the universe,” said Qian Lei, an associate researcher with the National Astronomical Observatories of the Chinese Academy of Sciences, in remarks broadcast by state broadcaster CCTV on Sunday.

“In theory, if there is civilization in outer space, the radio signal it sends will be similar to the signal we can receive when a pulsar (spinning neutron star) is approaching us,” Qian added.

The huge Chinese cosmic ear requires a radio silence within a five-kilometer radius, therefore the 8,000 residents of the eight villages in the vicinity of the telescope site were forced to abandon their homes.

According to state media, the displaced villagers would be compensated, in the form of cash or new houses, from a budget of $269 million.

The CCTV report said that FAST managed to receive radio signals from a pulsar as far as 1,351 light years from the Earth during its recent test. Source: http://www.jokpeme.com

Read More........→October 19, 2016

First detection of super-Earth atmosphere

Credit: ESA/Hubble, M. Kornmesser

NASA's Hubble Space Telescope has detected hydrogen and helium, but no water vapour, in the atmosphere of 55 Cancri e – the first time the atmosphere of a "super-Earth" has been analysed successfully. For the first time, astronomers were able to analyse the atmosphere of an exoplanet in the class known as super-Earths. Using data gathered with the NASA/ESA Hubble Space Telescope and new analysis techniques, the exoplanet 55 Cancri e is revealed to have a dry atmosphere without any indications of water vapour. The results, to be published in the Astrophysical Journal, indicate that the atmosphere consists mainly of hydrogen and helium. The international team, led by scientists from University College London (UCL), took measurements of the nearby exoplanet 55 Cancri e, a super-Earth with a mass of eight Earths. It is located in the planetary system of 55 Cancri, a star about 40 light-years from Earth. Using observations made by the Wide Field Camera 3 (WFC3) on board the NASA/ESA Hubble Space Telescope, the scientists were able to analyse the atmosphere in detail. The results were only made possible by exploiting a newly-developed processing technique. "This is a very exciting result,
because it's the first time that we have been able to find the spectral fingerprints that show the gases present in the atmosphere of a super-Earth," explains Angelos Tsiaras, a PhD student at UCL, who developed the analysing technique, along with his colleagues Ingo Waldmann and Marco Rocchetto. "The observations of 55 Cancri e's atmosphere suggest that the planet has managed to cling on to a significant amount of hydrogen and helium from the nebula from which it originally formed." Super-Earths like 55 Cancri e are thought to be the most common type of planet in our galaxy. They acquired the name 'super-Earth' because they have a mass larger than that of the Earth, but are still much smaller than the gas giants in the Solar System. The WFC3 instrument on Hubble has already been used to probe the atmospheres of two other super-Earths, but no spectral features were found in those previous studies. 55 Cancri e, however, is an unusual super-Earth, as it orbits very close to its parent star. A year on the exoplanet lasts for only 18 hours and temperatures on the surface are thought to reach around 2000 degrees Celsius. Because the planet orbits its bright parent star at such a small distance, the team was able to use their new technique to extract key information about the planet, during its transits in front of the host star. Observations were made by scanning the WFC3 very quickly across the star to create a number of spectra. By combining these observations and processing them through analytic software, the researchers were able to retrieve the spectrum of 55 Cancri e embedded in the light of its parent star. "This result gives a first insight into the atmosphere of a super-Earth. We now have clues as to what the planet is currently like and how it might have formed and evolved, and this has important implications for 55 Cancri e and other super-Earths," said Giovanna Tinetti, also from UCL. Intriguingly, the data also contain hints of the presence of hydrogen cyanide, a marker for carbon-rich atmospheres. "Such an amount of hydrogen cyanide would indicate an atmosphere with a very high ratio of carbon to oxygen," said Olivia Venot, KU Leuven, who developed an atmospheric chemical model of 55 Cancri e that supported the analysis of the observations. "If the presence of hydrogen cyanide and other molecules is confirmed in a few years time by the next generation of infrared telescopes, it would support the theory that this planet is indeed carbon rich and a very exotic place," concludes Jonathan Tennyson, UCL. "Although hydrogen cyanide, or prussic acid, is highly poisonous, so it is perhaps not a planet I would like to live on!"Source: http://www.futuretimeline.net/

Read More........→May 02, 2016

New microscope is 2,000 times faster

A new atomic force microscope developed by MIT can scan images 2,000 times faster than existing commercial models. This allows it to capture near-real-time video of nanoscale processes.

State-of-the-art atomic force microscopes (AFMs) are designed to capture images of structures as small as a fraction of a nanometre – a million times smaller than the width of a human hair. In recent years, AFMs have produced desktop-worthy close-ups of atom-sized structures, from DNA strands to individual bonds changing between molecules. But scanning these images is a meticulous, time-consuming process. AFMs have therefore been used mostly for static samples as they are too slow to capture active, changing environments. Now engineers at MIT have designed an atomic force microscope that scans images 2,000 times faster than existing commercial models. With this new high-speed instrument, the team produced images of chemical processes taking place at the nanoscale, at a rate that is close to real-time video. In one demonstration of the instrument’s capabilities, the researchers scanned a 70- by-70-micron sample of calcite as it was first immersed in deionised water and later exposed to sulphuric acid. Zooming into an area of interest, they observed the acid eating away at the calcite, expanding existing nanometre-sized pits in the material that quickly merged and led to a layer-by-layer removal of calcite along the material’s crystal pattern, over a period of several seconds.

Calcite immersed in deionised water.

 

Sulphuric acid creating pits in the calcite.

Professor of Mechanical Engineering at MIT, Kamal Youcef-Toumi, says the instrument’s sensitivity and speed will enable scientists to watch atomic-sized processes play out as high-resolution “movies.” “People can see, for example, condensation, nucleation, dissolution, or deposition of material, and how these happen in real-time – things that people have never seen before,” he says. “This is fantastic to see these details emerging. And it will open great opportunities to explore all of this world that is at the nanoscale.” The MIT researchers' achievement was made possible through an innovative new technique. This involved controlling the movement of the needle over the sample surface with two actuators (a small, fast scanner and a larger, slower one) in combination with a set of algorithms to ensure they never interfered with each other. At present, this method provides scans at eight to 10 frames per second, but further research is underway to increase this. “We want to go to real video, which is at least 30 frames per second,” Youcef-Toumi says. “Hopefully we can work on improving the instrument and controls so that we can do video-rate imaging while maintaining its large range and keeping it user-friendly. That would be something great to see.” The team's design and images, which are based on the PhD work of Iman Bozchalooi – now a postdoc in the Department of Mechanical Engineering – appear in the journal Source: Article

Read More........→December 22, 2015