© Provided by CBS NewsThe James Webb Space Telescope’s 21.3-foot-wide primary mirror, made up of 19 hexagonal ultra-smooth segments coated with a thin layer of gold to enhance reflectivity. / Credit: NASA

James Webb Space Telescope, the successor to the 31-year-old

Ariane 5 rocket, was rolled to the launch pad in Kourou, French Guiana, Thursday. Launch is targeted for 7:20 a.m. EST Christmas Day, weather permitting.

high-tech origami, deploying its solar array, antennas, radiators, its segmented primary mirror, its secondary mirror and the complex, fragile sunshade that is so essential to success.

© Provided by CBS NewsThe Webb telescope and its Ariane 5 rocket were hauled to the launch pad near Kourou, French Guiana, Thursday, setting the stage for blastoff Christmas Day. / Credit: ESA

check out and calibrate Webb’s instruments.

billions over budget, JWST will finally be ready to take center stage on the high frontier, carrying the hopes and dreams of thousands of engineers and astronomers around the world.

Looking for the oldest light there is

its epic quest to peer back in time to the end of the so-called dark ages, when the the blazing light of the first stars burned off the hydrogen fog of creation to travel freely through space. (What the heck does that mean?)

“It’s an infrared telescope,” said Paul Geithner, JWST’s technical project manager. “The main reason it was conceived in the first place was to see the end of the cosmic dark ages. And if you want to see objects from that epoch, the ultraviolet and the visible light they emitted so long ago has been red shifted all the way into the infrared spectrum.

super cold so that it’s not blinded by its own thermal emissions.”