[ti:Scientists: Moon Holds More Water than Ever Thought]
[by:www.21voa.com]
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[00:00.04]The moon may hold water in more places
[00:04.76]and in larger amounts than scientists have suggested in the past.
[00:12.88]The finding is based on two studies – published in Nature Astonomy
[00:19.40]– that examined new data from the U.S. space agency NASA.
[00:27.00]The discovery could be important for planned,
[00:30.72]long-term human bases on the moon.
[00:35.84]It could mean that enough resources exist on the moon itself
[00:40.84]to provide drinking water and possibly help produce rocket fuel.
[00:48.52]Until about 10 years ago, scientists believed the moon was mostly dry.
[00:57.16]Then, a series of findings provided evidence that water ice
[01:03.32]was widespread in small amounts on parts of the moon.
[01:09.72]The ice was thought to be in areas permanently blocked from sunlight.
[01:16.76]But in one of the new studies, NASA said it was able to confirm the presence
[01:23.48]of water molecules on sunlit parts of the lunar surface.
[01:31.08]The space agency says the identification came from data
[01:36.44]collected by its SOFIA airborne observatory.
[01:42.60]SOFIA is a Boeing 747SP aircraft equipped with a powerful telescope.
[01:52.52]The research was led by Casey Honniball
[01:56.68]of NASA's Goddard Space Flight Center in Maryland.
[02:02.80]"Without a thick atmosphere, water on the sunlit lunar surface
[02:08.72]should just be lost to space," Honniball said in a statement.
[02:14.32]"Yet somehow we're seeing it. Something is generating the water,
[02:20.76]and something must be trapping it there."
[02:25.36]Scientists have suggested the source of the water
[02:29.96]may have been comets, asteroids, solar wind or interplanetary dust.
[02:38.68]The new research provides evidence
[02:41.60]the water may be surviving on sunlit lunar surfaces
[02:46.48]because it is attached to minerals.
[02:51.16]"A lot of people think that the detection I've made is water ice,
[02:56.76]which is not true," Honniball told a news conference to announce the finding.
[03:03.60]"It's just the water molecules - because they're so spread out
[03:09.40]they don't interact with each other to form water ice or even liquid water."
[03:17.24]The second study centered on so-called "cold traps" on the moon.
[03:24.44]These are areas of the lunar surface that exist in a state of permanent darkness
[03:32.08]where temperatures are below about minus 160 degrees Celsius.
[03:40.92]Scientists say temperatures this cold can hold frozen water for billions of years.
[03:50.60]Researchers say they were able to reconstruct the size of the cold traps
[03:57.36]and where they sit from images and temperature readings
[04:02.92]from NASA's Lunar Reconnaissance Orbiter.
[04:07.92]They identified cold traps as small as a few meters across
[04:14.00]and others as wide as 30 kilometers.
[04:19.52]Planetary scientist Paul Hayne of the University of Colorado, Boulder
[04:25.92]led the research on cold traps.
[04:30.72]He estimated there are likely "tens of billions" of traps.
[04:36.84]"Since the little ones are too small to see from orbit,
[04:41.28]despite being vastly more numerous,
[04:44.80]we can't yet identify ice inside them," Hayne said.
[04:50.32]"Once we're on the surface, we will do that experiment."
[04:57.00]Hayne's team says the new research suggests
[05:01.24]more than 40,000 square kilometers of the moon's surface
[05:07.04]may have the ability to trap water in the form of ice.
[05:13.52]That estimate is 20 percent bigger than predicted in the past, Hayne said.
[05:21.96]Jacob Bleacher is the chief exploration scientist
[05:26.88]for NASA's Human Exploration and Operations Mission Directorate.
[05:34.64]He told reporters the agency believes it is very important
[05:40.12]to find out more about where the water came from and how accessible it is.
[05:48.88]"Water is extremely critical for deep space exploration.
[05:54.72]It's a resource of direct value for our astronauts," Bleacher said.
[06:02.84]He noted that water is heavy and costly to transport from Earth.
[06:10.48]"Anytime we don't need to pack water for our trip,
[06:14.96]we have an opportunity to take other useful items with us," he said.
[06:21.80]That may include materials that could be used
[06:25.48]to carry out bigger scientific experiments on the moon.
[06:30.92]I'm Bryan Lynn.
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END OF TRACK. "END OF TRACK." The two men bowed. "Whoever was that person you were talking to?" she enquired, as soon as they stood together. The took of triumph faded from her eyes, she had grown worn and weary. The roses were wilting on the walls, the lights were mostly down now. Hetty, looking in to see if anything was wanted, found herself driven away almost fiercely. I only saw Master Jervie once when he called at tea time, The year 1747 was opened by measures of restriction. The House of Lords, offended at the publication of the proceedings of the trial of Lord Lovat, summoned the parties to their bar, committed them to prison, and refused to liberate them till they had pledged themselves not to repeat the offence, and had paid very heavy fees. The consequence of this was that the transactions of the Peers were almost entirely suppressed for nearly thirty years from this time, and we draw our knowledge of them chiefly from notes taken by Horace Walpole and Lord Chancellor Hardwicke. What is still more remarkable, the reports of the House of Commons, being taken by stealth, and on the merest sufferance, are of the most meagre kind, sometimes altogether wanting, and the speeches are given uniformly under fictitious names; for to have attributed to Pitt or Pelham their[112] speeches by name would have brought down on the printers the summary vengeance of the House. Many of the members complained bitterly of this breach of the privileges of Parliament, and of "being put into print by low fellows"; but Pelham had the sense to tolerate them, saying, "Let them alone; they make better speeches for us than we can make for ourselves." Altogether, the House of Commons exhibited the most deplorable aspect that can be conceived. The Ministry had pursued Walpole's system of buying up opponents by place, or pension, or secret service money, till there was no life left in the House. Ministers passed their measures without troubling themselves to say much in their behalf; and the opposition dwindled to Sir John Hinde Cotton, now dismissed from office, and a feeble remnant of Jacobites raised but miserable resistance. In vain the Prince of Wales and the secret instigations of Bolingbroke and Doddington stimulated the spirit of discontent; both Houses had degenerated into most silent and insignificant arenas of very commonplace business. "It certainly will be. Miss Widgeon," answered Maria, with strictly "company manners." "One who has never had a brother exposed to the constant dangers of army life can hardly understand how glad we all feel to have Si snatched from the very jaws of death and brung back to us." "Just plug at 'em as you would at a crow, and then go on your way whistlin'?" persisted Harry. "Hurroo!" echoed Hennessey; "that's the ticket." "Come forward, keeper," continued the baron, "and state how these arrows came into your hands!" "Yes." HoMEJULIA京香2018下载
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