Sneak peek into James Webb Space Telescope, world's largest

The world's largest and most powerful space telescope unfolded its giant golden mirror for the last time on Earth on August 3, a key milestone before the $10 billion observatories, expected to launch this yearend. Credit: nasa.gov

The James Webb Space Telescope's 21 feet 4-inch (6.5 meter) mirror was commanded to fully expand and lock itself into place, NASA said -- a final test to ensure it will survive its million-mile (1.6 million kilometer) journey and is ready to discover the origins of the Universe. Credit: Northrop Grumman

Webb's primary mirror is made of 18 hexagonal segments coated with an ultra-thin layer of gold to improve its reflection of infrared light. The telescope will be shipped to French Guiana from the company's spaceport in Redondo Beach, California. NASA targeting October 31 for liftoff on an Ariane 5 rocket. Credit: AFP Photo

It will fly to space folded like a piece of origami artwork, which allows it to fit inside a 16-foot (5-meter) rocket fairing, and will then use 132 individual actuators and motors to bend each mirror into a specific position. Together, the mirrors will function as one massive reflector, to enable the telescope to peer deeper into the cosmos than ever before. Credit: NASA/Chris Gunn