An illustration shows how FAST receives radio waves emitted by distant pulsars, the rapidly rotating cores of dead stars. At left, a photo shows the huge telescope in Guizhou province. PROVIDED TO CHINA DAILY Chinese researchers have discovered six pulsars, which are superheavy remnants of massive stars, using its Five-hundred-meter Aperture Spherical Radio Telescope, known as FAST. It is the first time Chinese scientists have discovered pulsars using the world's largest single-dish radio telescope, thus opening a new era of Chinese original space discovery, Yan Yun, director of the National Astronomical Observatories of China, said on Tuesday. The first two pulsars, named J1859-01 and J1931-01, were discovered in August and were confirmed in September by the 64-meter radio telescope at Parkes Observatory in Australia. J1859-01 is 16,000 light years from Earth and rotates once every 1.83 seconds, while J1931-01 is 4,100 light years away and rotates once every 0.59 seconds, according to scientists. Since its completion in September 2016, FAST has discovered two dozen highly possible candidates for pulsars, said Li Di, the telescope's deputy chief engineer. Last week, FAST also confirmed four new pulsars, but their details are still being analyzed. Pulsars are superdense cores of massive stars that went supernova and died, hence they have incredible mass, extremely strong magnetic fields, and they spin like a clock and shoot out strong beams of electromagnetic radiation, Li said. The conditions on a pulsar are far more extreme than any lab simulation on Earth. Examining them and seeing how they interact with other stars can help us tackle major scientific issues, such as the origin and evolution of the universe, finding gravitational waves and navigating spacecraft. Li said FAST is set to be fully operational by the end of 2019. In the meantime, scientists there will continue to test FAST and cooperate with foreign scientists on space exploration. Located in a natural depression in Guizhou province, FAST consists of 4,600 triangular panels that form a receiving dish about the size of 30 soccer fields. Apart from its massive size, it also has unmatched accuracy and sensitivity, allowing scientists to find previously hidden stars, Li said. When we first received the pulsar signals, you can hear their frequency signals beep like the beating of a baby's heart, he said. Moreover, FAST is capable of surveying the night sky for multiple scientific data at once, ranging from galaxy structure to star explosions, while other telescopes can only manage one task at a time, he added. George Hobbs, a research scientist from the Commonwealth Scientific and Industrial Research Organization in Australia, said, The world's most exciting radio astronomy projects are happening in China with FAST, and it is a great honor for the Australian science community to be part of the process. Hobbs was also the leading scientist for the Parkes Pulsar Timing Array project, the telescope that confirmed China's pulsar findings. Since the discovery of pulsars in 1967, scientists have found more than 2,700 of them, more than half of which were found by Parkes Observatory, Hobbs said. Australia is the world leader in finding pulsars, but China will catch up really fast with FAST's help, he said. If FAST can find a binary system in which a pulsar is orbiting a black hole, this will be a discovery worthy of a Nobel Prize. tyvek event wristbandsbracelet maker onlinejordan wristband rubbercustom rubber wristbands
Fishermen sort fish in the busy fish market at Tanmen port, the largest port in Qionghai, Hainan province, on May 15, 2012.[Photo/CFP] Fish stocks off the Chinese coast have been effectively replenished this year due to successful bans, the Ministry of Agriculture said on Tuesday. Surveys conducted in August by institutes including the Chinese Academy of Fishery Sciences showed resources had increased greatly compared with early May, when the bans were imposed, Zhang Xianliang, head of the ministry's Fishery Administration Bureau, said at a news conference. Fish resources increased by 190 percent over the period in the Yellow Sea and Bohai Sea, more than tripled in the East China Sea, and increased by 70 percent in the South China Sea, he said. The fishing ban, which started on May 1, covered the entire Bohai Sea, the Yellow Sea, the East Sea and the South China Sea north of 12 degrees latitude, the ministry said in January. The duration of the ban varied from three months to four and a half months, with parts of the Yellow Sea and East Sea under the ban until Sept 16. This year's ban was the longest since they were first imposed in 1995. Only pole fishing was allowed during the ban. The enforcement against illegal fishing has been the strictest in years, with more than 10,300 people punished, Zhang said. In addition, 1,593 people were handed over to police for possible criminal penalties for fishing ban violations in inland waters, including the Yangtze River and parts of the Yellow River, Zhang said. In one case, two people, surnamed Qi and Wang, were sentenced to eight months and six months respectively in August for fishing with electrical devices in a major reservoir in Beijing. They caught 29.7 kilograms of fish on May 20, the ministry said. Liu Xinzhong, deputy head of the ministry's Fishery Administration Bureau, said China will strictly control the size of its deep ocean fishing fleet, and fewer than 3,000 Chinese fishing boats will operate in deep waters by 2020. Meanwhile, China will establish a blacklist for companies and individuals that violate fishing laws and regulations in deep waters, so they will be forbidden from fishing for a certain period of time, Liu said. [email protected]
