There are nights when the skies above this remote atoll are streaked with what seem to be strange shooting stars, burning with unnatural brightness and rumbling like thunder. Every now and then, there are stunning displays as the flares hurtle off in different directions, moving among scattered clouds as they trace serpentine paths in the sky.
Such celestial spectacles are not meteors from the heavens, but test warheads from ICBMs (intercontinental ballistic missiles). Since 1959, about one thousand missiles have been launched toward Kwajalein, where the U.S. Army’s Strategic Defense Command operates one of the world’s most sophisticated ranges for tracking space vehicles.
The missiles, nearly all of them launched from Vandenberg Air Force Base in California, soar hundreds of miles above the Pacific, releasing non-nuclear test warheads that splash down in or near the “world’s largest catcher’s mitt"--Kwajalein’s 950-square-mile, crescent-shaped lagoon.
The Marshall Islands were, in a sense, the place where the nuclear age began in earnest. It was here, on Eniwetok Atoll, that the United States detonated the first hydrogen bomb Nov. 1, 1952. Two hundred miles east and 1 1/2 years later, the most powerful blast ever created by the United States rocked Bikini Atoll with a force roughly a thousand times greater than that of the bomb dropped on Hiroshima at the end of World War II.
For the last 30 years, Kwajalein has been the major Air Force test site for gauging the accuracy of test warheads. No nuclear explosions have been carried out in the Marshall Islands since a 1963 treaty drove such testing underground. But reminders of nuclear weapons are scattered throughout the islands and are perhaps most vividly evident today on the Kwajalein atoll. On one of its islands, Mejatio, for example, about 380 refugees from the nearby atolls of Rongelap and Bikini wait for the day when they can move back to their home islands, which are still considered too radioactive for habitation.
Given its military role and remoteness, Kwajalein has long been shrouded from public view. But recently a reporter was granted a rare glimpse of Kwajalein, at a time when officials there are getting ready for what could be one of the busiest periods in its history as a missile range. This year, about a dozen test flights are scheduled, while engineers prepare for a battery of tests for Strategic Defense Initiative (SDI), popularly known as “Star Wars,” planned for the early 1990s.
A visitor finds that Kwajalein is not just an isolated place where the United States demonstrates its missile might. It is also an outpost of high-tech spying between the United States and the Soviet Union.
Ten times a year, on the average, Minuteman missiles thunder out of silos at Vandenberg on 4,950-mile, half-hour trips to Kwajalein. The missiles are the staple of the U.S. ICBM fleet, and are launched by the Air Force’s Strategic Air Command. And last year, the Navy began using Kwajalein for tests of the submarine-launched Trident 1 missile, carried by its Pacific fleet. The development was unusual because the Navy has traditionally tested its missiles in the South Atlantic, where three recent failures--including one last week--have plagued development of Trident 1’s successor, Trident 2.
The Air Force fared better with a test March 19 of its MX missile. The flight, the 18th such test of an MX, ended with seven dummy warheads landing in two target areas at Kwajalein.
Of U.S. missiles, the MX, along with Trident 2, are believed to be the most accurate, but test details as a rule are not discussed by the Department of Defense. But a clue about missile accuracy in general was found on a tiny island on the western edge of Kwajalein atoll.
Warheads are occasionally aimed at the island of Illeginni, Kwajalein’s only land-impact site. According to the atoll’s Range Command, only one-third of the roughly half-square-mile island is targeted by warheads launched at Vandenberg. And judging from craters on the island, the warheads found their targets. By good aim, good fortune, or both, a helipad within the targeted third of the island has survived unscathed over the years.
Testing warheads is a complex endeavor. Sensors and other instruments are built into the various components of ICBMs, including their mock warheads. The instruments radio telemetry data, enabling engineers to monitor internal systems during the missile’s flight, and, on occasion, better understand why a mission failed.
The single warhead of the Minuteman 2 missile, however, is encased in a metal shell, which would block the transmission of live radio telemetry during reentry. So the telemetry is routed to data recorders in the warheads, which are targeted for Kwajalein’s lagoon. Then divers hunt down the recorders on the bottom of the lagoon.
One of those recorders, from a test flight on July 7, 1987, was never found, according to a CBS Evening News report confirmed by the Department of Defense Jan. 11. Evidence of a beach party on an uninhabited Kwajalein island--Soviet cigarette packs, bug spray, and liquor bottles were found--led newsmen to suspect that the Soviets had made off with the data recorder, a possibility the Department of Defense has not ruled out.
Two Vladivostok-based Soviet intelligence vessels, the Zabaikalya and the Primorye, are dedicated to monitoring the U.S. tests at Kwajalein, according to James H. Biesterfield, the atoll’s special agent in charge of counterespionage. The boats, with few markings on their hulls, have a generic look that earned the nickname “Brand X.”
While the Soviets monitor U.S. operations over this remote range, the U.S. also keeps an electronic eye on the sky. Altair, the kingpin of the group of radars that record data on incoming U.S. test warheads, is also used to gather intelligence on Soviet and Chinese rocket launches, which soar eastward over the region when they are depositing satellites in equatorial orbits. Last year, Altair tracked 68 foreign launches, about two-thirds of which originated in the Soviet Union, according to Gary W. Ahlgren, deputy manager of the Kiernan Reentry Measurements Site (Krems), the atoll’s main technical installation.
Krems is on Roi-Namur, the atoll’s northeasternmost and second largest island at 380 acres. Here giant coconut-eating crabs still scurry in the underbrush and dirt roads and crumbling underground tunnels still connect scattered ruins from the pre-World War II Japanese occupation of the atoll.
Today Krems is the site of some of the most advanced radars in the world. Altair, for example, has a massive, 150-foot dish antenna, and is devoted most of the time to tracking satellites in geosynchronous orbits 22,300 miles from Earth. Once it spots a foreign launch, two other Krems radars, called Alcor and MMW (for millimeter wave) are used to make images--some as detailed as good quality photographs--of the rocket’s payload. The images often help aerospace experts determine what is being put in orbit, according to Range Command officials.
When tracking incoming U.S. test warheads, Altair spots the vehicles the moment they soar over the horizon, when they are more than 2,200 miles away. At that point, the warheads are a few hundred miles over an area not far from the Hawaiian islands.
As the warheads descend toward the atoll, Krems radars are used to make detailed recordings of the return radio signals, or “signatures,” bounced off them. Each of the radars has a different wavelength, so each provides a different signature. According to Kenneth R. Roth, manager of the Krems facility, comparing signatures made with radars and other sensors of different wavelengths may well turn out to be the key to distinguishing warheads from decoys--one of the major unsolved technical problems of the Strategic Defense Initiative.
The next round of SDI experiments at Kwajalein, scheduled to begin in 1990, will help determine whether the SDI is headed toward deployment in some form or toward failure as an overly ambitious research project.