The final three of 18 primary mirrors built for the James Webb Space Telescope (JWST) have arrived at Goddard Space Flight Center for integration prior to a scheduled launch in 2018, principal optical subcontractor Ball Aerospace & Technologies Corp. said Wednesday. The last three of the 18 flight primary mirror segments arrived at NASA's Goddard Space Flight Center in Greenbelt, Md., on Dec. 16, 2013. After traveling across the country, the mirrors were prepped to enter a Goddard cleanroom for inspections. Courtesy of NASA Goddard/Chris Gunn. The 18 beryllium primary mirror segments are ready for telescope integration. Once on orbit, they will work together as one 21.3-ft (6.5-m) primary mirror, the largest mirror ever flown in space and the first to deploy in space. Ball Aerospace also developed the secondary mirror, tertiary mirror and fine-steering mirror. "Ball's sophisticated mirror architecture will provide James Webb with the most advanced infrared vision of any space observatory ever launched by NASA," said Robert Strain, Ball Aerospace president. "A huge amount of teamwork was needed to meet the exacting requirements for the telescope's optical design and we're eager to see the results." The premier observatory for the next decade, the JWST will be stationed 1 million miles (1.5 million km) from Earth – some four times farther than the moon. The JWST will be the most powerful space telescope ever built, able to detect the light from the first galaxies ever formed and explore planets around distant stars. It will study every phase of the universe's history, ranging from the first luminous glows after the big bang, to the formation of stellar systems capable of supporting life on planets like Earth, to the evolution of our solar system. Boulder, Colo.-based Ball began an incremental process of shipping the finished mirrors to Goddard in September 2012. The mirrors are housed in custom shipping containers designed specifically for the multiple cross-country trips the mirrors made through eight US states during manufacturing. Each container is hermetically sealed to handle atmospheric pressure changes caused by shipping from high elevations such as Boulder to locations at or near sea level, such as Greenbelt. Prime contractor on the project is Northrop Grumman Corp. Aerospace Systems. For more information, visit: http://jwst.gsfc.nasa.gov or www.ballaerospace.com