首页
登录
职称英语
Scientists have taken a giant leap toward making possible the dream of buildi
Scientists have taken a giant leap toward making possible the dream of buildi
游客
2023-12-22
80
管理
问题
Scientists have taken a giant leap toward making possible the dream of building a powerful telescope on the moon that could withstand even the harshest of lunar conditions.
Writing in Thursday’s edition of the journal Nature, they said they coated a special type of liquid surface with a layer of silver to make a highly reflective mirror like one that could be used in any future, moon-based telescope.
"It’s the breakthrough that we need," lead researcher Ermanno Borra of Universite Laval in Quebec, Canada, said in a telephone interview. "If you want to have a liquid mirror telescope on the moon, you need the right liquid. If you don’t have the right liquid, forget it. It’s as simple as that." Borra envisions a telescope with a liquid mirror measuring 66 feet to 328 feet wide.
Such a telescope, which has drawn NASA’s interest, could provide astronomers on Earth unprecedented views into distant reaches of the universe, studying objects far more faint even than NASA’s planned James Webb Space Telescope, due for a 2013 launch. Astronomers hope such an instrument could allow them to study the early phases of the universe after the Big Bang.
Advocates say a large telescope on the moon would be more cheaply and easily built using a liquid mirror rather than a conventional glass one. The researchers think any liquid-mirror telescope on the moon would not come before 2020 at the earliest.
The scientists made use of a liquid made of "ionic salts" that remains fluid at super-low temperatures. They deposited a thin layer of chromium particles on the liquid, then added a layer of silver particles to complete the mirror.
Liquid mirror telescopes differ from conventional ones in that their primary mirrors, which gather and focus light, are made of reflective liquid instead of polished glass. The liquid can be poured into a spinning container, spreading out to make a thin, smooth, parabolic shape that can be used as a telescope mirror, the researchers said.
The silver layer that is created is completely smooth, highly reflective, can stay stable for months, and the ionic liquid that it covers does not evaporate, the researchers said. [br] When would the liquid-mirror telescope on the moon come out at the earliest?
选项
A、After 2020.
B、Before 2020.
C、After 2013.
D、Before 2013.
答案
A
解析
转载请注明原文地址:http://tihaiku.com/zcyy/3296180.html
相关试题推荐
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
Americanshavefourprimaryavenuesformakingfriends:atwork,atschool,
随机试题
TheUSForeignServiceisadivisionoftheStateDepartment.America【S1】__
TopicALetterofApologyForthispart,youareallowed30minutestowri
Seguence[img]2019m9x/ct_eyyjsdz2019j_eyyjsdiq_0212_201909[/img]Whichofthefo
[originaltext]M:Look,I’msorryIdidn’tturnupforthematchyesterday,but
从家庭居住特征着眼,如果有人是与老年父母同住或仅夫妻两人居住,那么他的家庭所处的
(2018年真题)按照附认股权和债券本身能否分开来划分,附认股权证的公司债券可分
关于法的分类的说法正确的是()。A.依据法的创制方式和表达形式的不同,可以把法分
学习一种新材料时运用联想假借意义,对记忆有帮助的这种方法称为()。 A.语义
工程进度款的计算主要涉及()A、工程质量的检验和施工进度计划 B、工程的计量和
低合金高强度结构钢质量等级分为( )级。A.3 B.4 C.5 D.6
最新回复
(
0
)