National missile defense test tonight

The Pentagon tonight will conduct the first systemwide test of the controversial

national missile defense system. The test is expected to be a major factor

in President Clinton's decision this fall as to whether the technology is

mature enough to proceed.

Sometime during the four-hour "launch window" — overnight between 10

p.m. EDT and 2 a.m. — the following events will occur, a Pentagon spokesman

said Wednesday:

* The Pentagon will launch a modified Minuteman target missile from

Vandenberg Air Force Base, Calif.

* About 20 minutes later and 4,300 miles away, the interceptor missile

will launch from Kwajalein atoll in the Marshall Islands.

* Another 10 minutes after that, Pentagon officials expect that the

interceptor will knock the Minuteman from the sky about 100 miles above

the Pacific Ocean.

The Pentagon will conduct a press briefing 30 minutes after the test.

Although officials will know whether the interceptor hit the target, detailed

analysis will not be available for another week or two, the spokesman said.

"We'll take a look in great detail at all aspects of the test shot — of the supporting systems, the radars, the command and control.and have

a very thorough understanding," Rear Adm. Craig Quigley said.

As the clock ticks down to launch time, however, critics continue to pressure the White House not to deploy the planned system.

Fifty Nobel Prize-winning scientists with the Federation of American Scientists sent a letter Thursday to President Clinton, asking him to leave the critical decision to the next president.

"We urge you not to make the decision to deploy an anti-ballistic missile system during the remaining months in your administration. The system would offer little protection and would do grave harm to this nation's core security interests," the scientists wrote.

NMD critics complain that the Pentagon's tests are designed to help the system succeed, that the planned system will not work against easy-to-manufacture countermeasures and that building the system will destabilize world security because Russia and China believe it to be a threat.