Mission to Study Comet Boosted by Aerojet Propulsion

SACRAMENTO, Calif., Jan. 13, 2005 -- Aerojet, a GenCorp Inc. (NYSE: GY) company, provided essential lifting power to place the NASA spacecraft “Deep Impact” in orbit on Wednesday, Jan. 12, and the company’s propulsion systems will support every phase of this unique mission. Aerojet’s large second stage liquid engine and its third stage control thruster on the Delta II launch vehicle aided in the launch of Deep Impact on its Discovery Mission to study the Comet Tempel 1. Launched from Cape Canaveral Air Force Station, Fla., the “Deep Impact” spacecraft will perform fly-by maneuvers of Tempel 1 after releasing an “impactor” to collide with the comet and study the collision outcome. Small Aerojet thrusters will provide spacecraft adjustment during cruise, and guide the impactor into the comet’s path after separation from the spacecraft. Those thrusters will also position the fly-by spacecraft as it observes and records the impact, including characteristics of the ejected material blasted from the crater and the structure of the crater’s interior.

“Deep Impact” is the eighth of 10 NASA Discovery Missions. The Discovery Missions aim to achieve ground-breaking science within strict cost and schedule limitations. Aerojet has provided propulsion for every Discovery Mission launched to date.

Aerojet is a world-recognized aerospace and defense leader principally serving the missile and space propulsion, defense and armaments markets. GenCorp is a leading technology-based manufacturer of aerospace and defense products and systems with a real estate segment that includes activities related to the entitlement, sale, and leasing of the company’s excess real estate assets. Additional information about Aerojet and GenCorp can be obtained by visiting the companies’ Web sites at http://www.Aerojet.com and http://www.GenCorp.com.