KEKAHA, Kaua'i — Tomorrow morning, the crew of the USS Lake Erie will be scanning the sky with every surveillance tool the ship has.

The Lake Erie crew will be looking for a ballistic missile, which is to be fired from the USS Tripoli more than 250 miles north of Kaua'i.

For this latest test of its Aegis anti-ballistic missile system, the Lake Erie crew knows only that the target will be fired between 7:30 and 10 a.m. The Lake Erie will have less than 20 minutes from the time the target missile has been fired to detect it and shoot it down.

"It's like trying to hit a bullet with a bullet," said Pacific Missile Range Facility spokesman Tom Clements.

This is only the second time the military has tried to intercept a target missile in its terminal phase (the last few seconds before impact) using its ship-based Aegis weapons system.

The first try, which was successful, was on May 23, 2006, and also involved the Lake Erie and the Pacific Missile Range Facility on Kaua'i.

The difference this time is that the target missile will be launched from another ship instead of from the ground on Kaua'i.

If you imagine the arc of a missile flight, the military divides it into three sections — the three- to five-minute boost phase, the midcourse cruise beyond the Earth's atmosphere and the final 30 seconds to one minute as it's plummeting to its destination.

The Aegis systems aboard some Navy ships were originally designed to take out ballistic missiles during their midcourse flight, using a direct hit from a Standard Missile-3, said Chris Taylor, a spokesman for the Missile Defense Agency.

The ship-based Aegis system has hit its target 13 of the 15 times it has used the SM-3s in tests at the Pacific Missile Range Facility, Taylor said.

For the end-stage hit, the Lake Erie will fire two Standard Missile-2 Block IV models equipped with fragmenting warheads. They'll be fired within seconds of each other and if the first one makes the strike, the second one will self-destruct, Taylor said.

The whole event will be so far north of Kaua'i that no one will be able to see it and the debris from the missiles will fall in the open ocean, Taylor said.

The cost of the test will run about $40 million, Taylor said.

The Missile Defense Agency co-manages the Navy's Aegis program, partners with the Army on its ground-based Patriot missiles and has primary responsibility for other, developing anti-ballistic missile technologies. It's an evolution of the Strategic Defense Initiative begun by President Reagan and has an $8.7 billion budget this year.

The MDA is growing in response to increased threats from "rogue nations" on the world stage, Taylor said.

In 1972, there were just a handful of potentially unfriendly nations with ballistic missile capabilities. Now, a map on the agency Web site lists more than 20 countries with such capability.

"Several hundred military, civilian and defense contractor people are actively involved in the test, from those aboard ship (Lake Erie), the Mobile Launch Platform (Tripoli), on the ground at the Pacific Missile Range Facility on Kaua'i, plus command and control centers at Pearl Harbor; Colorado Springs, Colo.; and Omaha, Neb., and in the national capital region," Taylor said.