The world´s largest and most powerful space telescope unfolded its giant golden mirror for the last time on Earth, a key milestone before the $10 billion observatory is launched later this year.
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.
“It´s like building a Swiss watch at 40-feet-tall… and getting it ready for this journey that we take into the vacuum at minus 400 degrees Fahrenheit (-240 Celsius), four times further than the Moon,” said Scott Willoughby of lead contractor Northrop Grumman.
He was speaking at the company´s spaceport in Redondo Beach, California, from where the telescope will be shipped to French Guiana to be launched on an Ariane 5 rocket, with NASA targeting October 31 for liftoff.
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.
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.