气体巨星的形成之谜
文章来源:未知 文章作者:enread 发布时间:2015-08-21 07:28 字体: [ ]  进入论坛
(单词翻译:双击或拖选)
Queen's University researcher Martin Duncan has co-authored a study that solves the mystery of how gas giants such as Jupiter and Saturn1 formed in the early solar system. In a paper published this week in the journal Nature, Dr. Duncan, along with co-authors Harold Levison and Katherine Kretke (Southwest Research Institute), explain how the cores of gas giants formed through the accumulation of small, centimetre- to metre-sized, "pebbles2.
 
"As far as we know, this is the first model to reproduce the structure of the outer solar system - two gas giants, two ice giants (Uranus and Neptune), and a pristine3 Kuiper belt beyond Neptune," says Dr. Duncan.
 
The currently accepted, "standard model" states that these cores formed through collisions between much larger bodies 100-1,000 kilometres in size, known as planetesimals. However, this model would not have allowed the cores to form quickly enough to capture the gases that make up their atmosphere in the early solar system.
 
The model created by Dr. Duncan and his team shows that collisions and accumulation of the so-called pebbles would have allowed the cores to form much more rapidly. In addition, the new model accurately4 predicts the formation of one to four gas giant planets; consistent with what we see in the outer solar system.
 
"It is a relief, after many years of performing computer simulations of the standard model without success, to find a new model which is so successful," says Dr. Duncan.
 
Read the study, Growing the Gas-Giant Planets by the Gradual Accumulation of Pebbles in Nature.


点击收听单词发音收听单词发音  

1 Saturn tsZy1     
n.农神,土星
参考例句:
  • Astronomers used to ask why only Saturn has rings.天文学家们过去一直感到奇怪,为什么只有土星有光环。
  • These comparisons suggested that Saturn is made of lighter materials.这些比较告诉我们,土星由较轻的物质构成。
2 pebbles e4aa8eab2296e27a327354cbb0b2c5d2     
[复数]鹅卵石; 沙砾; 卵石,小圆石( pebble的名词复数 )
参考例句:
  • The pebbles of the drive crunched under his feet. 汽车道上的小石子在他脚底下喀嚓作响。
  • Line the pots with pebbles to ensure good drainage. 在罐子里铺一层鹅卵石,以确保排水良好。
3 pristine 5BQyC     
adj.原来的,古时的,原始的,纯净的,无垢的
参考例句:
  • He wiped his fingers on his pristine handkerchief.他用他那块洁净的手帕擦手指。
  • He wasn't about to blemish that pristine record.他本不想去玷污那清白的过去。
4 accurately oJHyf     
adv.准确地,精确地
参考例句:
  • It is hard to hit the ball accurately.准确地击中球很难。
  • Now scientists can forecast the weather accurately.现在科学家们能准确地预报天气。
TAG标签: solar system gas
发表评论
请自觉遵守互联网相关的政策法规,严禁发布色情、暴力、反动的言论。
评价:
表情:
验证码:点击我更换图片