James Webb Space Telescope

NASA engineer Ernie Wright looks on as the first six flight ready James Webb Space Telescope's primary mirror segments are prepped to begin final cryogenic testing at NASA's Marshall Space Flight Center. 

This represents the first six of 18 segments that will form NASA's James Webb Space Telescope's primary mirror for space observations. Engineers began final round-the-clock cryogenic testing to confirm that the mirrors will respond as expected to the extreme temperatures of space prior to integration into the telescope's permanent housing structure.

The James Webb Space Telescope (sometimes called JWST) will be a large infrared telescope with a 6.5-meter primary mirror. The project is working to a 2018 launch date

Image Credit: NASA/MSFC/David Higginbotham
Explanation from: http://www.jwst.nasa.gov/primarymirror.html