久久亚洲国产成人影院-久久亚洲国产的中文-久久亚洲国产高清-久久亚洲国产精品-亚洲图片偷拍自拍-亚洲图色视频

Americas

US missile interceptor test launches debate

(USA TODAY)
Updated: 2007-05-25 09:40
Large Medium Small

In space, a 15,000-mph collision between a missile and an interceptor rocket makes no noise. But down on Earth, a scientific and political debate is getting very loud.

US missile interceptor test launches debate
This 08 March 2006 US Department of Defense handout image shows a Standard Missile - 3 (SM-3) being launched from the USS Lake Erie (CG 70) in a Missile Defense Agency and Japan Defense Agency joint test in the Pacific.? [Agencies]
US missile interceptor test launches debate
Barring low clouds, a test target missile will launch Thursday from Alaska's Kodiak Island and should encounter an interceptor rocket from Vandenberg Air Force Base in California, says US Missile Defense Agency spokesman Richard Lehner.

It's a technology that scientists say won't work effectively.

Such midcourse interceptors, designed to destroy their targets in space at their trajectory's peak, already are in place in Alaska and California.

A plan to place a $3.5 billion interceptor base in Poland by 2012 has generated friction with Russian President Vladimir Putin. Missile defense will be discussed at the G-8 summit June 6-8 in Germany.

The interceptor test is part of the agency's plan to spend $49 billion over the next five years to deploy and test missile defense technologies.

But physicists such as Frederic Lamb of the University of Illinois Urbana-Champaign, who co-headed a 2003 American Institute of Physics report on missile defense, are saying that midcourse interceptors are losers from a physics standpoint.

According to Lamb: Aside from the difficulty of the interceptor connecting with the missile when both are free-falling outside of the Earth's atmosphere, it will be impossible to detect a decoy missile. Atmospheric drag identifies the qualities of a missile, such as size, speed and heat. Without those signatures, a balloon, for example, would register on radar the same way a rocket would.

Related readings:
US missile interceptor test launches debateRussia capable of hitting US missile shield
US missile interceptor test launches debateUS dual missile test fails off Hawaii
US missile interceptor test launches debate
Pentagon announces new missile sale to Japan

The test will take place about 100 miles above the Pacific Ocean, where the atmosphere is thin. Analysts consider anything above 62 miles altitude to be a region of diminished or non-existent air drag, says physicist David Wright of the Union of Concerned Scientists, a science advocacy group in Cambridge, Mass.

"Outside the Earth's atmosphere, the drag is zero on a warhead and a decoy alike," Lamb says. "This is an intractable problem. There is no signature that distinguishes a warhead that can't be cheaply counterfeited."

Lehner says by e-mail: "Critics forget that we have a variety of sensors that are extremely capable of discriminating countermeasures and decoys from lethal warheads."

Rep. Ellen Tauscher, D-Calif., chairwoman of the House Armed Services Subcommittee on Strategic Forces, says, "We've invested billions in missile defense since the 1980s." She favors more proven shorter-range missile defense systems: "It's got to be better than a science project."

分享按鈕
主站蜘蛛池模板: 国产精品国产三级国产专播 | 天堂8资源在线官网资源 | 欧美一级特黄高清免费 | 久久国产午夜精品理论片34页 | 狠狠色狠狠色综合 | 亚洲高清免费在线观看 | 成人国产精品久久久免费 | 中文字幕亚洲精品第一区 | 黄色天堂在线 | 国产精品资源在线 | 国产9191精品免费观看 | 欧美一级aⅴ毛片 | 欧美在线高清 | 国产亚洲一区二区三区 | 亚洲精品不卡视频 | 玖玖99视频 | 成年网站免费视频黄 | 久草视频在线网 | 欧美在线区 | gdcm01果冻传媒 | 伊人色在线观看 | 在线亚洲精品视频 | 偷偷操不一样的久久 | 九九久久精品国产 | 男女一级 | 中字毛片 | 国产精品亚洲精品久久成人 | 久久久久久久久久久福利观看 | 在线视频免费观看a毛片 | 99小视频| 日本在线www| 高清国产在线播放成人 | 91日本在线视频 | 欧美日韩一区二区三区在线观看 | 国内免费视频成人精品 | 九九九精品 | 成年18网站免费视频网站 | 日本男人天堂 | 亚洲黄区| 国产欧美专区在线观看 | 日本人一级毛片视频 |