三级aa视频在线观看-三级国产-三级国产精品一区二区-三级国产三级在线-三级国产在线

  Home>News Center>World
         
 

NASA launches comet-smashing spacecraft
(Agencies)
Updated: 2005-01-13 08:08


The "Deep Impact" spacecraft is launched by a Delta II launch vehicle at 1:47:08 p.m. EST from Space Launch Complex 17B, Cape Canaveral Air Force Station, Florida, January 12, 2005. [Reuters]

Nothing like this has ever been attempted before.

Little is known about Comet Tempel 1, other than that it is an icy, rocky body about nine miles long and three miles wide. Scientists do not even know whether the crust will be as hard as concrete or as flimsy as corn flakes.

"One of the scary things is that we won't actually know the shape and what it looks like until after we do the encounter," said Jay Melosh, a planetary geologist at the University of Arizona.

The comet will be more than 80 million miles from Earth when the collision takes place — on the sunlit side of the comet, NASA hopes, in order to ensure good viewing by spacecraft cameras and observatories. The resulting crater is expected to be two to 14 stories deep, and perhaps 300 feet in diameter.

Scientists stress that Deep Impact will barely alter the comet's orbital path around the sun and will not put either the comet or a chunk of it on a collision course with Earth. In the 1998 movie "Deep Impact," astronauts try to blow up a comet in hopes of saving the Earth, but the comet winds up being split in two and one section slams into the Atlantic, creating a huge tsunami on the East Coast.
Page: 123



 
  Today's Top News     Top World News
 

Beijing rejects call for official talks on charter flights

 

   
 

UK sees China arms embargo lifted in July

 

   
 

Minister: Sino-US trade ties 'pretty good'

 

   
 

China, Portugal sign seven pacts

 

   
 

US ends fruitless Iraq weapons hunt

 

   
 

3G mobile go-ahead scheduled for 2005

 

   
  US ends fruitless Iraq weapons hunt
   
  Powell sees troops returning this year
   
  NASA launches comet-smashing spacecraft
   
  Ohio court dismisses election challenges
   
  Mark Thatcher agrees to bargain in coup case
   
  Torrential storm tears up US western states
   
 
  Go to Another Section  
 
 
  Story Tools  
   
  News Talk  
  Are the Republicans exploiting the memory of 9/11?  
Advertisement
         
主站蜘蛛池模板: 欧美激情一区二区三区蜜桃视频 | 深夜小视频在线观看 | 国产vr一区二区在线观看 | 日本免费的一级绿象 | 一区影院 | 一级免费看片 | 三级三级三级网站网址 | 精东视频污 | 99久久一香蕉国产线看观看 | 黄色亚洲视频 | 欧美亚洲免费久久久 | 免费高清资源黄网站在线观看 | 三级国产在线 | 亚洲第一视频在线播放 | 亚洲成a人片在线观看www | 欧美成人片在线 | 免费在线看黄色片 | 亚洲色图欧美一区 | 亚洲第一页综合 | 日韩欧美在线综合网 | 韩国一级黄色大片 | 一级特一级特色生活片 | 国产福利一区二区 | 在线观看免费网址大全 | 久久精品a亚洲国产v高清不卡 | 欧美一级视频在线观看欧美 | 俄罗斯一级毛片免费播放 | 亚洲第一页在线视频 | 国产日韩欧美一区二区三区视频 | 亚洲日韩中文字幕在线播放 | 制服丝袜99| 国产91精选在线观看网站 | 91国视频在线| 欧美精品久久一区二区三区 | 国产网红在线观看 | 91中文字幕在线一区 | 亚洲欧美一区二区三区二厂 | 欧美日韩国产高清 | 日韩高清在线亚洲专区vr | 在线观看欧洲成人免费视频 | 在线播放亚洲精品 |