Fourth US Air Force SBIRS satellite sends first images back to Earth

The U.S. Air Force's fourth Space Based Infrared System (SBIRS) satellite transmitted its first images back to Earth. The milestone, known as "first light," occurred in February when the SBIRS GEO Flight-4 satellite, built by Lockheed Martin, turned on its powerful sensors for the first time during space vehicle checkout. SBIRS GEO Flight-4 is the latest satellite to join the Air Force's orbiting missile warning constellation. More

(Source: Space Daily - May 5)