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LOS ANGELES nike air vapormax flyknit grises baratas , Nov. 5 (Xinhua) -- An international team of astronomers discovered emission from clouds of cold cosmic dust surrounding the Earth-sized temperate world Proxima b, discovered in 2016 and the closest planet to the Solar System, and believed there may be more hidden planets yet to find.
"The dust around Proxima is important because, following the discovery of the terrestrial planet Proxima b, it's the first indication of the presence of an elaborate planetary system, and not just a single planet nike air vapormax flyknit azul baratas , around the star closest to our Sun," Guillem Anglada, the lead author of the new study, was quoted as saying in a news release.
Dust belts are the remains of material that did not form into larger bodies such as planets. The particles of rock and ice in these belts vary in size from the tiniest dust grain, smaller than a millimetre across, up to asteroid-like bodies many kilometres in diameter.
Proxima Centauri nike air vapormax flyknit blancas baratas , the closest star to the Sun, is a faint red dwarf lying just four light-years away in the southern constellation of Centaurus (The Centaur).
According to the new Atacama Large Millimeter Array (ALMA) observations, detailed in a study to appear in Astrophysical Journal Letters, dust appears to lie in a belt that extends a few hundred million kilometres from Proxima Centauri and has a total mass of about one hundredth of the Earth's mass. This belt is estimated to have a temperature of about -230 degrees Celsius, as cold as that of the Kuiper Belt in the outer Solar System.
There are also hints in the ALMA data of another belt of even colder dust about ten times further out. If confirmed, the nature of an outer belt is intriguing nike air vapormax pure platinum baratas , given its very cold environment far from a star that is cooler and fainter than the Sun. Both belts are much further from Proxima Centauri than the planet Proxima b, which orbits at just four million kilometres from its parent star.
Co-author Pedro Amado from the Instituto de Astrofísica de Andalucía (CSIC), Granada, Spain, explains that this observation is just the start.
"These first results show that ALMA can detect dust structures orbiting around Proxima. Further observations will give us a more detailed picture of Proxima's planetary system. In combination with the study of protoplanetary discs around young stars, many of the details of the processes that led to the formation of the Earth and the Solar System about 4600 million years ago will be unveiled. What we are seeing now is just the appetiser compared to what is coming!" Amado explains the implications of the discovery.
LONDON nike air vapormax inneva baratas , Nov. 1 (Xinhua) -- The British manufacturing sector continued its run of robust growth in October, benefiting from improved economic conditions globally.
The MarkitCIPS purchasing managers' index (PMI) for October rose from September's 56.0 to 56.3, continuing an unbroken 15-month run of growth.
Markets and experts had expected a slight decline to 55.9, and the PMI figure released on Wednesday is above the long-term trend for this set of data.
Production and new order volumes continued to rise at robust rates, as companies benefited from rising inflows of new export business and strong domestic market conditions. The new orders index rose to 57.7 from 56.6 in September.
The domestic market was the prime source of new contract wins, although new export business also continued its history of growth.
Samuel Tombs nike air vapormax utility baratas , chief UK economist with data analysis firm Pantheon Macroeconomics, told Xinhua: "Developed economies are seeing a rebound in global trade flows and the UK is benefiting from that, being quite an open economy."
Companies saw improved intakes of new work from clients in the USA, mainland Europe, South America and Australia, in some cases aided by the sterling exchange rate.
Sterling has fallen substantially since the Brexit referendum vote nike air vapormax moc baratas , dropping from 1.48 U.S. dollars to 1.33 U.S. dollars on Wednesday.
"Sterling has weakened a lot in the last couple of years and that has now filtered through to the manufacturing sector," said Tombs.
However, the figures reveal a mixed benefit, with the sector growing because of global conditions but still lagging the growth of other developed economies.
Tombs said: "If you look at the UK's manufacturing sector compared to the eurozone, it is lagging behind, because of a slowdown in UK economic growth."
Graphics: GT
China will face severe demographic challenges in the next 25 years as the country's working-age population is predicted to shrink from last year's 66.3 percent to 56.9 percent of the total in 2030.
The aging population will swell from 16.1 to 25.2 percent which could seriously test China's social and economic development nike air vapormax 2.0 baratas , experts said.
The number of those aged between 16 and 59 will decrease to 896 million in 2020 and 824 million in 2030, while those aged 60 and over will grow to 253 million in 2020 and 365 million in 2030, according to new data provided by the Population and Development Studies Center at the Renmin University of China to the Global Times on Tuesday.
Data from the National Bureau of Statistics (NBS) shows that in 2015, China's working age population was 911 million and there were 222 million senior citizens.
"China's current demographic structure is severely distorted, as the country now faces problems such as low fertility, an aging society and gender imbalance. This may hinder economic development as well as social stability in the long run nike air vapormax 95 baratas ," said Mu Guangzong, a professor at Peking University's Institute of Population Research.
Yi Fuxian, a controversial scientist at the University of Wisconsin-Madison in the US, recently warned at the Boao Forum for Asia on March 25 that China has entered a "low fertility trap" and that its aging population will impede economic development, usin. Cheap Jerseys Cheap Wholesale Jerseys Cheap Sports Jerseys Cheap Jerseys China Cheap Retro Jerseys Cheap Authentic Sports Jerseys Cheap Authentic Sports Jerseys Cheap Throwback Sports Jerseys Cheap NHL Hockey Jerseys Cheap NFL Football Jerseys |
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