Missile defense proves successful again

CNN:

The United States successfully tested a sea-based component of its missile defense shield Thursday evening, intercepting a ballistic missile with a dummy warhead over the Pacific Ocean, the U.S. Missile Defense Agency said.

The exercise was the 19th successful test in 23 attempts of the system -- known as the Aegis Ballistic Missile Defense Program -- since 2002.

A target missile was fired from Hawaii about 5:40 p.m. (11:40 p.m. ET) and was tracked by Navy ships hundreds of miles away.

The USS Hopper, one of three Navy ships tracking the launch, fired an interceptor missile, which struck the target about 100 miles above the Earth. The process -- from launch to shoot-down -- took less than five minutes, according to the U.S. military.

The United States plans to use the sea-based system on Navy Aegis-class ships to protect against incoming short- to medium-range missiles fired from hostile countries. Eighty-six of the ships eventually will have the capability.

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Danger Room reports:

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In a statement, Riki Ellison, the plugged-in chief of the Missile Defense Advocacy Association, said the ARAV “represented a ballistic missile similar in speed, acceleration and burn of the same short range missiles fired by North Korea on July 2nd and 4th of this year.”

Equally important, this was an “ascent phase” shoot-down: According to a Missile Defense Agency news release, the interceptor struck the target 1oo miles above the Pacific Ocean. By Ellison’s count, this is only the second ascent-phase intercept in 23 at-sea firings by the Aegis missile defense system.

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What the "ascent phase" means means is that it is prior to apogee, (See this graphic.) which assumes the boost phase systems did not work. Other systems target the missile if it makes it though these first two phases. There is more on the system here. Hat tip to Graham for this information and clarification.