The U.S. is expected to test its Terminal High Altitude Area Defense system, or THAAD, sometime in the next few days.
The test has been planned for months, though its exact date won't be announced until after it happens.
The test takes on a new meaning in light of recent intercontinental ballistic missile tests out of North Korea.
North Korea has conducted almost a dozen missile tests so far this year — at least, that's how many we know of.
Most recently, North Korea claimed its first successful ICBM launch ever. Kim Jong-un reportedly ordered it on the eve of July 4, America's Independence Day.
THAAD uses radar to detect incoming short- and medium-range ballistic missiles both inside and outside Earth's atmosphere. Then, an interceptor is launched to destroy the incoming threat.
The defense system isn't designed to take on the kind of intercontinental missile North Korea launched, though.
The looming U.S. test will reportedly happen in Alaska. Officials from the Department of Defense said the THAAD system will go up against an intermediate-range ballistic missile.
UPDATED July 11: The U.S. Missile Defense Agency tested the THAAD system Tuesday and reports the test was successful.