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' G% V, |3 w0 V* P【SeraMyu之地】美少女战士音乐剧主题论坛s Pluto a Planet? The Votes Are In ! x- p4 Q" r" ^: h0 t. C: {【SeraMyu之地】美少女战士音乐剧主题论坛Release No.: seramyu.cn# o8 _" ]- C; {
2014-25 , g" M4 Q. h7 B K+ }' u$ K7 w, {For Release: ( g, n: v, m* U+ B
Monday, September 22, 2014 - 10:00amseramyu.cn( O% k0 O; V$ h) J! Q) e$ N
Cambridge, MA - ' J1 ?! h: t7 ?) V: F3 ?" j8 kWhat is a planet? For generations of kids the answer was easy. A big ball of rock or gas that orbited our Sun, and there were nine of them in our solar system. But then astronomers started finding more Pluto-sized objects orbiting beyond Neptune. Then they found Jupiter-sized objects circling distant stars, first by the handful and then by the hundreds. Suddenly the answer wasn't so easy. Were all these newfound things planets?seramyu.cn% P @* P9 A- k+ a( C. c
; f, d% e3 I' d+ K【SeraMyu之地】美少女战士音乐剧主题论坛Since the International Astronomical Union (IAU) is in charge of naming these newly discovered worlds, they tackled the question at their 2006 meeting. They tried to come up with a definition of a planet that everyone could agree on. But the astronomers couldn't agree. In the end, they voted and picked a definition that they thought would work. 5 p# R! O# H, o# a5 ]【SeraMyu之地】美少女战士音乐剧主题论坛 2 J1 e$ p& f4 h0 useramyu,seramyu之地,美少女战士,美少女战士音乐剧,美少女战士舞台剧,ミュージカル美少女戦士セーラームーン,Musical Pretty Soldier Sailor Moon,大山アンザ,神戸みゆき,黒木マリナ,高木ナオ,穂坂優子,笠原竜司,望月祐多The current, official definition says that a planet is a celestial body that:& z6 o# C1 C7 |
J! f f: A2 Mis in orbit around the Sun,5 B4 K" s$ M i& X9 X# N) `$ c/ b4 y
is round or nearly round, and【SeraMyu之地】美少女战士音乐剧主题论坛: t) r( Z7 P W* y4 V7 y
has "cleared the neighborhood" around its orbit. a0 s% V4 M3 r0 w9 d- c( V. U
But this definition baffled the public and classrooms around the country. For one thing, it only applied to planets in our solar system. What about all those exoplanets orbiting other stars? Are they planets? And Pluto was booted from the planet club and called a dwarf planet. Is a dwarf planet a small planet? Not according to the IAU. Even though a dwarf fruit tree is still a small fruit tree, and a dwarf hamster is still a small hamster.seramyu,seramyu之地,美少女战士,美少女战士音乐剧,美少女战士舞台剧,ミュージカル美少女戦士セーラームーン,Musical Pretty Soldier Sailor Moon,大山アンザ,神戸みゆき,黒木マリナ,高木ナオ,穂坂優子,笠原竜司,望月祐多% ?. Z& v% P- g( Z& o' T o
, s8 {7 [& \4 Y: _【SeraMyu之地】美少女战士音乐剧主题论坛Eight years later, the Harvard-Smithsonian Center for Astrophysics decided to revisit the question of "what is a planet?" On September 18th, we hosted a debate among three leading experts in planetary science, each of whom presented their case as to what a planet is or isn't. The goal: to find a definition that the eager public audience could agree on!/ o2 K/ x4 J- Y6 \8 k& I
2 h6 h. U F6 w+ s1 k0 Kseramyu,seramyu之地,美少女战士,美少女战士音乐剧,美少女战士舞台剧,ミュージカル美少女戦士セーラームーン,Musical Pretty Soldier Sailor Moon,大山アンザ,神戸みゆき,黒木マリナ,高木ナオ,穂坂優子,笠原竜司,望月祐多Science historian Dr. Owen Gingerich, who chaired the IAU planet definition committee, presented the historical viewpoint. Dr. Gareth Williams, associate director of the Minor Planet Center, presented the IAU's viewpoint. And Dr. Dimitar Sasselov, director of the Harvard Origins of Life Initiative, presented the exoplanet scientist's viewpoint.# i% L/ \, B" w# H( Q4 s# o- \+ d9 F
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Gingerich argued that "a planet is a culturally defined word that changes over time," and that Pluto is a planet. Williams defended the IAU definition, which declares that Pluto is not a planet. And Sasselov defined a planet as "the smallest spherical lump of matter that formed around stars or stellar remnants," which means Pluto is a planet. 5 J! q& }2 U M g$ U6 @2 x! _7 Sseramyu,seramyu之地,美少女战士,美少女战士音乐剧,美少女战士舞台剧,ミュージカル美少女戦士セーラームーン,Musical Pretty Soldier Sailor Moon,大山アンザ,神戸みゆき,黒木マリナ,高木ナオ,穂坂優子,笠原竜司,望月祐多# @' o7 J' c/ B5 f& d8 }
After these experts made their best case, the audience got to vote on what a planet is or isn't and whether Pluto is in or out. The results are in, with no hanging chads in sight.seramyu,seramyu之地,美少女战士,美少女战士音乐剧,美少女战士舞台剧,ミュージカル美少女戦士セーラームーン,Musical Pretty Soldier Sailor Moon,大山アンザ,神戸みゆき,黒木マリナ,高木ナオ,穂坂優子,笠原竜司,望月祐多- t1 k2 w/ H: F# M8 f! L
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According to the audience, Sasselov's definition won the day, and Pluto IS a planet. . R @8 Y) M( ~ O+ f9 T$ tseramyu.cn1 L) ^ B: j0 ]5 e V; d
The video of the debate and audience vote can be seen on YouTube at https://www.youtube.com/user/ObsNights. m6 M2 J5 d( w' ?# c% h
% h: o& A; n* KHeadquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe. : X5 @ u4 M$ s8 S【SeraMyu之地】美少女战士音乐剧主题论坛8 K. K) A+ A4 z6 H+ S
For more information, contact:seramyu.cn7 w9 v7 z9 w' t# `5 e8 |
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David A. Aguilar ' \7 |( ^& s' F5 G8 hDirector of Public Affairsseramyu.cn! Q9 l( q4 w* ]2 A$ t) i) g: [5 l
Harvard-Smithsonian Center for Astrophysics/ R1 m& y' v, {. w' o5 i5 q
617-495-7462 + h9 W' r9 J, ?4 T( i【SeraMyu之地】美少女战士音乐剧主题论坛daguilar@cfa.harvard.edu【SeraMyu之地】美少女战士音乐剧主题论坛! D6 k& K9 W" V4 O' ~8 X
【SeraMyu之地】美少女战士音乐剧主题论坛# D* K3 O @4 U2 g9 S
Christine Pulliam# R5 H5 B6 R8 A n
Public Affairs Specialist 9 G4 P- [# r9 W- @# x: B' AHarvard-Smithsonian Center for Astrophysics / b8 o( w$ e1 z; N/ a617-495-7463【SeraMyu之地】美少女战士音乐剧主题论坛/ O8 J3 c7 \+ e, @+ U cpulliam@cfa.harvard.edu作者: さむい 时间: 2014-10-6 11:24