The H-IIA rocket with the Global Precipitation Measurement Core Observatory aboard rolled out to Launch Pad 1 at 1:04 p.m. on Feb. 27 (Japan time) at Tanegashima Space Center, Japan. The rocket is scheduled to lift off during a launch window that opens at 3:37 a.m. (JST) on Feb. 28. (1:37 p.m. Feb. 27 EST).
After an overnight rainstorm, clear skies and a blustery wind set the stage as the largest sliding door in the world opened. For the past month inside the Vehicle Assembly Building, launch services provider Mitsubishi Heavy Industries has been preparing the rocket. The GPM Core Observatory is safely nestled inside the white fairing, the nose cone of the rocket that will protect the satellite during launch.
An announcement in both Japanese and English over the outdoor loudspeakers asked all personnel not working during the rollout to clear out of the 250-meter radius of the launch area. Then, to the sound of beeping two-tone notes familiar to large moving vehicles, the mobile launcher began inching outside.
The gray H-shaped umbilical tower emerged first, "H-IIA F-23" painted on the sides. The umbilical tower has swooping connections to the rocket, providing power, air, and communication to the onboard systems of both the GPM Core Observatory and the rocket itself. About nine hours before launch, engineers use the umbilical tower to fuel the first and second stages of the rocket with liquid hydrogen and liquid oxygen -- each in their own tanks until mixed to create explosive thrust at liftoff.
H-IIA rocket No. 23 glided into view next, orange body, white tip, and the GPM logo on one side. From a distance it doesn't look big, but then tiny people walking beside it came into view, giving scale to the 174 foot (53 meter) tall H-IIA atop the mobile launcher.
Full rocket assembly occured on the mobile launcher inside the Vehicle Assembly Building, which protects the rocket from wind and rain. Then the whole assembly is moved out to the launch pad as a single unit. Two green "crawlers" drive into their slots at the base of mobile launcher, like pins into a pre-made hole. Then they lift the mobile launcher off the ground and slowly take it out. The crawlers drive themselves automatically with their onboard computers, running in sync and overseen by people in the crawler's cabin. The crawlers each have 56 wheels and travel about 1.2 mph (2 kph) across the 525 yards (480 meters) to the launch pad.
After 22 minutes, the mobile launcher, the rocket, and the GPM spacecraft in the fairing stopped between the red and white towers of Launch Pad 1, almost ready to fly.