Some Hawai'i residents noticed an odd light in the western sky yesterday morning, which was most likely an unannounced rocket launch from the Pacific Missile Range Facility.

Kane'ohe residents Bill and Linda Riddle saw the light before sunrise, about 5:40 a.m., rising from the western horizon and moving faster than satellites that are sometimes visible crossing the sky at night.

"It was not nearly as fast as a shooting star, nor as slow as most orbital satellites," Bill Riddle said.

"Its brightness dimmed considerably as it approached 60 plus degrees from the horizon, and it subsequently appeared to slow somewhat and to separate into two and then three close-knit 'reflections' that were about as bright as satellites viewed at that hour," he said.

On hearing the description, Pacific Missile Range Facility spokesman Tom Clement confirmed that a rocket launch occurred at the time when the Riddles saw the light.

"That was us. The time and the direction he was looking lead me to believe that," Clement said. He said he was surprised that O'ahu residents could see it.

The launch was a project of the Missile Defense Agency. No further information about that launch was available, he said.

The Pacific Missile Range Facility, a Navy base on Kaua'i's west side, conducts a range of military research and training, including tests of the sea-based national missile-defense system. A February 2005 test involving the Aegis Ballistic Missile Defense Weapons System resulted in a direct hit by a rocket from the USS Lake Erie on a target rocket fired from the missile range.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.