Photos: Delta 2 rocket revealed after mobile gantry rollback

Ground crews at Vandenberg Air Force Base in California retracted a mobile gantry away from the Delta 2 rocket Monday afternoon, revealing the 128-foot-tall (39-meter) booster on its launch pad awaiting liftoff with a new polar-orbiting weather observatory.

The United Launch Alliance Delta 2 rocket is set for blastoff at 1:47:02 a.m. PST (4:47:02 a.m. EST; 0947:02 GMT) Tuesday with the first spacecraft in NOAA’s Joint Polar Satellite System. JPSS 1 will go into orbit around 500 miles (800 kilometers) high and use five instruments to measure temperature and humidity in the atmosphere, solar radiation reflected off the Earth, ozone health, and other key data to aid weather forecasters.

Fitted with nine strap-on solid rocket boosters made by Orbital ATK and a first stage RS-27A engine and second stage AJ10-118K engine, both from Aerojet Rocketdyne, the Delta 2 rocket is poised for its 154th mission Tuesday. One more Delta 2 launch is planned in late 2018 before ULA retires the workhorse rocket.

Credit: ULA/Jeff Spotts
Credit: ULA/Jeff Spotts
Credit: ULA/Jeff Spotts
Credit: ULA/Jeff Spotts
Credit: ULA/Walter Scriptunas II
Credit: ULA/Walter Scriptunas II
Credit: ULA/Walter Scriptunas II

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