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|By Xinhua writers Quan Xiaoshu & Yu Fei
BEIJING hydro flask wine tumbler red sale , July 19 (Xinhua) -- Are we alone? Scientists say they are on the cusp of answering the age-old question about extraterrestrial (ET) life.
"We are lucky to be in a special era, with the next generation of giant telescopes on the way. There may be some exciting discoveries in the following 10 to 20 years," says Mao Shude, director of the Center for Astrophysics of the Beijing-based Tsinghua University.
According to mainstream scientific opinion, it is possible that extraterrestrial life exists, as the Earth is not unique in the universe. Our galaxy has hundreds of billions of stars, many with solar-like planetary systems, and there are hundreds of billions of galaxies in the universe. So it' s reasonable to infer that Earth-like planets might be common hydro flask wine tumbler green sale , and the universe could teem with life.
"I think primitive life is likely to be abundant, but intelligent life might be rarer," says Mao, also director of the Galaxy and Cosmology Division of the National Astronomical Observatories of China (NAOC), Chinese Academy of Sciences.
The next generation of giant telescopes might help astronomers resolve some long-standing issues, such as analyzing the spectrum of distant planets, making it possible to detect biomarkers of life.
Biomarkers are certain elements that might indicate the existence of life. An important biomarker, oxygen molecules hydro flask 12 oz coffee black sale , without supporting life, can only last for a short time compared with the 13.7 billion-year history of the universe.
Oxygen easily reacts with other elements, and Mars appears red as a result of oxidation. "If we find a lot of oxygen molecules in the atmosphere of an extraterrestrial planet, they are probably produced by life activities," Mao explains.
wton more than 300 years ago when he discovered that larger telescopes could not form clearer images due to atmospheric distortions.
But today, after years of development, many observatories around the world, including those with telescopes of 8 to 10 meters in diameter hydro flask 12 oz coffee white sale , are equipped with adaptive optics systems.
Adaptive optics is a technology that aims to correct the distortions induced by atmospheric turbulence. The system is mainly composed by three parts: a wavefront sensor, a deformable mirror and a real time controller. The wavefront sensor is like the eye of the system, and it measures the light distortions a few hundred or even thousand times in one second, so that the turbulence distortion almost looks like a cartoon played frame by frame to the system; the real time controller acts like a super fast brain, and it calculates how correction should be applied and sends commands to the deformable mirror; and finally, like the hand of the system, the deformable mirror actually carries out those commands, and changes its surface shape accordingly to correct the distortions before the arrival of the next command.
The next generation of ground-based telescopes hydro flask 12 oz coffee red sale , including the Thirty Meter Telescope (TMT), the Giant Magellan Telescope (GMT) and the European Extremely Large Telescope (E-ELT), will have better adaptive optics systems, so they will be central to future observations, says Feng Lu, an associate researcher with the NAOC.
Compared with space telescopes, ground-based telescopes can be larger and connected to more instruments, and can work longer and look deeper into space. The adaptive optics technology will improve their resolution close to or even above space telescopes hydro flask 12 oz coffee yellow sale , making them capable of observation tasks previously impossible on the ground, such as tracking extra-solar planet candidates, Feng says.
For example, with the assistance of adaptive optics, TMT will have a resolving power and sensitivity much greater than the Hubble Space Telescope when it goes into use around mid-2020s. One of its major tasks will be to analyze the spectrum of extra-solar planets.
But the next generation of space telescopes will also revolutionize astronomy. The Transiting Exoplanet Survey Satellite (TESS), to be launched by the U.S. National Aeronautics and Space Administration (NASA) in 2017, is one of them.
Kepler, TESS' predecessor launched by NASA in 2009 hydro flask 12 oz coffee pink sale , is the world's first space observatory dedicated to the search for planets outside our solar system. So far, Kepler has confirmed 2,325 extra-solar planets, more than 70 percent of the total. Twenty-one of them are Earth-like, staying in habitable zone and within twice the size of Earth.
While both can monitor planetary transits, TESS is capable of carrying out all-sky surveys, while Kepler can only observe a small part of our region of the Milky Way.
"More importantly, TESS will look for extra-solar planets in orbit around the brightest stars hydro flask 16 oz coffee black sale , which will help analyze the physical nature of these planets. Kepler's planets are often around dim stars, which makes it difficult to carry out follow-up studies," Mao says.
"The number of planets that TESS will detect is not necessarily much more (than Kepler), but the quality will be more advanced."
Part of the worldwide SETI effort, the project uses observational data from Puerto Rico's Arecibo Observatory, the world's current largest telescope, and the Green Bank observatory. The data, taken "piggyback" or "passively" while the telescopes are used for other scientific projects hydro flask 16 oz coffee white sale , are divided into small chunks and sent to millions of home computers for analysis. The software searches for signals with variations that cannot be ascribed to noise, and hence possibly contain information.
So far, about 9 million volunteers in 226 countries have analyzed a total of 15 years of data from the Arecibo telescope, according to Dan Werthimer, co-founder and chief scientist of the SETI@home project.
"We have identified about 100 very short radio bursts, about one millionth of a second long, that we don't fully understand,
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