The Missile Defense Agency quietly tested a “kill vehicle” over the weekend, successfully showing that the nation's first line of defense can block the threat of ballistic missiles.

At hypersonic speeds, the Raytheon-made warhead -- a 120-pound spacecraft that has been described as “a telescope mounted on a pack of propane cylinders” -- operates at the edge of space to seek out and ram into threats, ultimately destroying them.

On the afternoon of Sat., Jan. 26, the Agency successful launched and tested the craft, which they call an Exoatmospheric Kill Vehicle or EKV, from Vandenberg Air Force Base in California. It’s a key element of Boeing’s Ground-based Midcourse Defense (GMD) system, which acts as the nation’s shield.

GMD is the first and only operationally deployed missile defense program to defend against long-range ballistic missile attacks, such as inbound ICBMs.

And that shield is apparently sturdy.

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Instead of using a traditional warhead, EKV destroys the threat by colliding with it using only the force of impact -- a process known as “hit-to-kill.”

At ramming speed
GMD has sensors on land, sea and space to detect threats. Once a threat is detected, a three-stage solid rocket booster blasts the EKV into space. Once outside the Earth’s atmosphere, it uses advanced multi-color sensors to detect the incoming warheads.

The EKV has its own propulsion, communications link, discrimination algorithms, guidance and control system. It also has its own computers and a rocket motor to steer in space.

In the tests over the weekend, the three-stage booster shot this kill vehicle to a designated point in space, where it separated from its booster and executed a variety of pre-planned maneuvers in space.

A target missile launch was not included in this flight test, but the Missile Defense Agency says all components performed as designed. The program will assess and evaluate system performance in a flight environment using data the agency gathered during this test.

Engineering data from this test will also be used to improve confidence for future intercept missions.

The test is the latest in an extensive series ordered after the Flight Test Ground-Based Interceptor (FTG)-06 system failure in December 2010 -- and a critical first step in returning GMD to successful intercept testing.

The EKV has already had eight successful intercepts throughout the life of the program

Ballet dancer turned defense specialist Allison Barrie has traveled around the world covering the military, terrorism, weapons advancements and life on the front line. You can reach her at wargames@foxnews.com  or follow her on Twitter @Allison_Barrie.