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[新闻]科学家首次在彗星上发现极光

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Data from NASA instruments aboard the ESA (European Space Agency) Rosetta mission have helped reveal that comet 67P/Churyumov-Gerasimenko has its own far-ultraviolet aurora. It is the first time such electromagnetic emissions in the far-ultraviolet have been documented on a celestial object other than a planet or moon. A paper on the findings was released today in the journalNature Astronomy.
On Earth, aurora (also known as the northern or southern lights) are generated when electrically charged particles speeding from the Sun hit the upper atmosphere to create colorful shimmers of green, white, and red. Elsewhere in the solar system, Jupiter and some of its moons -- as well as Saturn, Uranus, Neptune, and even Mars -- have all exhibited their own version of northern lights. But the phenomena had yet to be documented in comets.
Rosetta is space exploration's most traveled and accomplished comet hunter. Launched in 2004, it orbited comet 67P/Churyumov-Gerasimenko (67P/C-G) from Aug. 2014 until its dramatic end-of-mission comet landing in Sept. 2016. The data for this most recent study is on what mission scientists initially interpreted as "dayglow," a process caused by photons of light interacting with the envelope of gas -- known as the coma -- that radiates from, and surrounds, the comet's nucleus. But new analysis of the data paints a very different picture.
"The glow surrounding 67P/C-G is one of a kind," said Marina Galand of Imperial College London and lead author of the study. "By linking data from numerous Rosetta instruments, we were able to get a better picture of what was going on. This enabled us to unambiguously identify how 67P/C-G's ultraviolet atomic emissions form."
The data indicate 67P/C-G's emissions are actually auroral in nature. Electrons streaming out in the solar wind -- the stream of charged particles flowing out from the Sun -- interact with the gas in the comet's coma, breaking apart water and other molecules. The resulting atoms give off a distinctive far-ultraviolet light. Invisible to the naked eye, far-ultraviolet has the shortest wavelengths of radiation in the ultraviolet spectrum.
Exploring the emission of 67P/C-G will enable scientists to learn how the particles in the solar wind change over time, something that is crucial for understanding space weather throughout the solar system. By providing better information on how the Sun's radiation affects the space environment they must travel through, such information could ultimately can help protect satellites and spacecraft, as well as astronauts traveling to the Moon and Mars.
"Rosetta is the gift that keeps on giving," said Paul Feldman, an investigator on Alice at the Johns Hopkins University in Baltimore and a co-author of the paper. "The treasure trove of data it returned over its two-year visit to the comet have allowed us to rewrite the book on these most exotic inhabitants of our solar system -- and by all accounts there is much more to come."
NASA Instruments Aboard ESA's Rosetta
NASA-supplied instruments contributed to this investigation. The Ion and Electron Sensor (IES) instrument detected the amount and energy of electrons near the spacecraft, the Alice instrument measured the ultraviolet light emitted by the aurora, and the Microwave Instrument for the Rosetta Orbiter (MIRO) measured the amount of water molecules around the comet (the MIRO instrument includes contributions from France, Germany, and Taiwan). Other instruments aboard the spacecraft used in the research were the Italian Space Agency's Visible and InfraRed Thermal Imaging Spectrometer (VIRTIS), the Langmuir Probe (LAP) provided by Sweden, and the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) provided by Switzerland.
Rosetta was an ESA mission with contributions from its member states and NASA. Rosetta's Philae lander, which successfully landed on the comet in November 2014, was provided by a consortium led by the German Aerospace Center in Cologne; Max Planck Institute for Solar System Research in Gottingen, Germany; the French National Space Agency in, Paris; and the Italian Space Agency in Rome. A division of Caltech, NASA's Jet Propulsion Laboratory in Southern California managed the U.S. contribution of the Rosetta mission for NASA's Science Mission Directorate in Washington. JPL also built the MIRO and hosts its principal investigator, Mark Hofstadter. The Southwest Research Institute (San Antonio and Boulder, Colorado), developed the Rosetta orbiter's IES and Alice instruments and hosts their principal investigators, James Burch (IES) and Joel Parker (Alice).
For more information on the U.S. instruments aboard Rosetta, visit:htt👍p://roset👍ta.jpl.nas👍a.go👍v
More information about Rosetta is available at:ht👍tp://w👍ww.es👍a.in👍t/rosetta


来自Android客户端1楼2020-09-24 19:58回复
    来自欧洲航天局罗塞塔号航天飞机上的NASA仪器的数据有助于揭示67P / Churyumov-Gerasimenko彗星具有自己的远紫外线极光。 这是首次在远非行星或月球的天体上记录到这种远紫外线中的电磁辐射。 关于发现的论文今天在《自然天文学》杂志上发表。
    在地球上,当从太阳飞来的带电粒子撞击到高层大气时,会产生绿色,白色和红色的七彩闪光,从而产生极光(也称为北极或南方的光)。 在太阳系的其他地方,木星及其一些卫星-以及土星,天王星,海王星,甚至火星-都展示了自己的北极光版本。 但是这种现象尚未在彗星中记录下来。
    罗塞塔(Rosetta)是太空探索中旅行最多,成就最出色的彗星猎人。 它于2004年发射升空,从2014年8月开始一直围绕着67P / Churyumov-Gerasimenko彗星(67P / CG)旋转,直到2016年9月其重大的任务终止彗星着陆。 称为“日光”,是由光子与彗星核辐射并围绕其的气体包层(称为彗形象差)相互作用而引起的过程。 但是对数据的新分析却描绘出了截然不同的景象。
    伦敦帝国理工学院的玛丽娜·加兰德说:“围绕67P / C-G发出的光是其中的一种。” “通过链接来自众多Rosetta仪器的数据,我们能够更好地了解正在发生的事情。这使我们能够清楚地确定67P / C-G紫外线原子发射的形式。”
    数据表明67P / C-G的排放实际上是极光。 在太阳风中流出的电子-从太阳流出的带电粒子流-与彗星彗形象差中的气体相互作用,分解水和其他分子。 产生的原子发出独特的远紫外光。 肉眼看不见的远紫外线在紫外线光谱中的辐射波长最短。
    探索67P / C-G的排放将使科学家能够了解太阳风中的粒子如何随时间变化,这对于理解整个太阳系的太空天气至关重要。 通过提供有关太阳辐射如何影响其必须穿越的太空环境的更好信息,此类信息最终可以帮助保护卫星和航天器以及前往月球和火星的宇航员。
    论文的合著者,巴尔的摩约翰霍普金斯大学爱丽丝研究人员保罗·费尔德曼说:“罗塞塔是不断馈赠的礼物。” “它在对彗星进行的两年访问中返回的数据宝库,使我们能够重写有关太阳系中这些最奇特的居民的书,而且从所有方面来看,还有很多书要写。”
    ESA的Rosetta上的NASA仪器
    NASA提供的仪器有助于这项调查。 离子和电子传感器(IES)仪器检测到航天器附近的电子数量和能量,爱丽丝(Alice)仪器测量了极光发出的紫外线,罗塞塔轨道器微波仪(MIRO)测量了周围水分子的数量 彗星(MIRO仪器包括法国,德国和台湾的贡献)。 该研究中使用的航天器上的其他仪器是意大利航天局的可见和红外热成像光谱仪(VIRTIS),瑞典提供的Langmuir探针(LAP)以及瑞士提供的用于离子和中性分析的罗塞塔轨道器光谱仪(ROSINA)。 。
    罗塞塔(Rosetta)是ESA的一个任务,其成员国和NASA对此做出了贡献。 罗塞塔的菲莱着陆器由科隆德国航空航天中心领导的财团于2014年11月成功降落在彗星上; 德国哥廷根的马克斯·普朗克太阳能系统研究所; 法国巴黎国家航天局; 和罗马的意大利航天局。 美国国家航空航天局位于南加州的喷气推进实验室是加州理工学院的一个部门,负责管理美国在罗塞塔号任务中为美国宇航局科学任务部在华盛顿所做的贡献。 JPL还建立了MIRO,并接待了主要调查员Mark Hofstadter。 西南研究所(科罗拉多州圣安东尼奥市和博尔德市)开发了Rosetta轨道仪的IES和Alice仪器,并接待了主要研究人员James Burch(IES)和Joel Parker(Alice)。
    有关罗塞塔号上美国乐器的更多信息,请访问:ht👍tp://rose👍tta.jpl.nas👍a.go👍v
    有关Rosetta的更多信息,请访问:htt👍p://ww👍w.es👍a.in👍t/rosetta


    来自Android客户端3楼2020-09-24 20:00
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      有点像缺了半张脸的木乃伊


      来自Android客户端4楼2020-09-24 21:01
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        这石头或许是一个雕刻的好原材料头和颈都有了


        IP属地:北京来自Android客户端6楼2020-09-24 23:20
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          不会吧不会吧,不会彗星都有磁场了吧,那样的话月球殖民直接pass


          IP属地:广东来自Android客户端7楼2020-09-25 18:19
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            厉害……


            IP属地:广东来自Android客户端8楼2020-09-25 21:07
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              67p长得真像个橡皮鸭子


              IP属地:安徽来自Android客户端9楼2020-12-13 18:05
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                算极光吗?不就是电离气体吗!


                IP属地:北京10楼2020-12-15 13:48
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                  不太可能吧,那么小的彗星


                  IP属地:广东来自Android客户端11楼2020-12-15 15:16
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                    太阳风与彗星外层气体相互作用的结果 ,很正常吧。


                    IP属地:广西12楼2020-12-15 17:26
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