总之大家看图就明白了，冥王星重新成为行星，恭喜冥姐回归太阳系大家庭= =1 M$ a) x- {# d f & k; k+ s. A% ^sailormoon-musical.coms Pluto a Planet? The Votes Are In 1 M4 C7 k6 e2 }/ W& L1 K【SeraMyu之地】美少女战士音乐剧主题论坛Release No.: sailormoon-musical.com X- F# j c3 ^
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For Release: % P8 L' s9 M- ~2 E/ H. E) Z- \Monday, September 22, 2014 - 10:00am! @8 h$ o5 d$ G0 V5 I+ ]+ F4 z$ }. Y
Cambridge, MA -+ L$ [6 F5 I; _+ K
What 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?7 T+ I- s- U3 x2 N' Z
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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. + A- G( C2 K5 ~& A1 \3 _sailormoon-musical.com + G: l$ o$ d. n) Z* k8 l" [; @% @The current, official definition says that a planet is a celestial body that: 1 j% k/ A( |! t2 Q# n【SeraMyu之地】美少女战士音乐剧主题论坛; }2 b/ O9 e' w+ j; f
is in orbit around the Sun,sailormoon-musical.com1 M# g6 ?3 h, V
is round or nearly round, and 4 R$ D* \( k- b, x2 _3 oseramyu,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has "cleared the neighborhood" around its orbit. $ E, W; r! }2 F: {7 W【SeraMyu之地】美少女战士音乐剧主题论坛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. * }/ J; x" {4 f. i- ^$ a【SeraMyu之地】美少女战士音乐剧主题论坛6 C/ F; `8 V" G6 `9 Y
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!【SeraMyu之地】美少女战士音乐剧主题论坛# F: B5 K+ K1 S1 h. Z
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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. ' }2 w @8 e$ h3 g8 e2 q; i2 O( Q5 `
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.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+ U9 W' D# T7 L" x7 M
' M) d8 F6 J5 a! [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. V c2 S1 A1 D2 |6 P; Q
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8 |" m! ?) x/ |. L9 \# w9 r* P5 X
According to the audience, Sasselov's definition won the day, and Pluto IS a planet.! v9 E7 `% i) s! @& U7 G" Q+ T
, Q8 L' \+ t, W" Y; c+ ]4 m5 xThe video of the debate and audience vote can be seen on YouTube at https://www.youtube.com/user/ObsNights. ( \- l: U% V: Qsailormoon-musical.com' G5 |8 m) m$ k" n8 ^: l! {
Headquartered 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.! ~: e% X! r- u, `
* Y8 _' g* f% l" K【SeraMyu之地】美少女战士音乐剧主题论坛For more information, contact:【SeraMyu之地】美少女战士音乐剧主题论坛0 B9 _# w0 I% P- Y7 u
9 e* q7 r5 \5 U3 YDavid A. Aguilar # x" C: t8 C' S0 EDirector of Public Affairs【SeraMyu之地】美少女战士音乐剧主题论坛- M+ T3 a8 ^- s3 V' \8 b: }
Harvard-Smithsonian Center for Astrophysicssailormoon-musical.com( k/ b. v& \0 d: O/ O
617-495-7462 0 z6 B. K9 _4 @0 N3 I* R. ddaguilar@cfa.harvard.edusailormoon-musical.com9 r* Y( b; X2 _' j( w! [1 W
( Q8 j5 n7 S/ L8 t) F7 ^! O4 \【SeraMyu之地】美少女战士音乐剧主题论坛Christine Pulliam. o4 i7 c) g- h& ^1 `
Public Affairs Specialist & T4 {% ~. I+ s" HHarvard-Smithsonian Center for Astrophysics , ^3 M; [" e4 N# F617-495-7463sailormoon-musical.com( j5 U+ t# R) S cpulliam@cfa.harvard.edu作者: さむい 时间: 2014-10-6 11:24
