Ariane 5

The James Webb Space Telescope fired its rocket thrusters for the first time late Saturday to line up for course toward an observing post nearly a million miles from Earth, then deployed a high-rate communications antenna Sunday to transmit science data to the ground.

The James Webb Space Telescope, a NASA-led international collaboration that took nearly 30 years and $10 billion to get to the launch pad, finally left Earth with a Christmas morning rocket ride from a European spaceport in South America, setting off on a mission to hunt for the first light in the universe. That was just the easy part.

An Ariane 5 rocket has lifted off from French Guiana on a mission to send the James Webb Space Telescope toward a point a million miles from Earth. The powerful European rocket blasted off at 7:20 a.m. EST (1220 GMT).

If you want to see the faint, stretched-out light from the first stars and galaxies that began shining at the end of the cosmic dark ages a few hundred million years after the Big Bang, you’re going to need a big telescope. But not just any big telescope.

Teams in French Guiana positioned a European Ariane 5 rocket into its starting blocks Thursday, ready for liftoff Christmas morning with the nearly $10 billion James Webb Space Telescope, the most expensive science instrument ever to leave planet Earth.

Spaceflight Now’s Editor, Stephen Clark, speaks with NASA’s Keith Parrish, the commissioning manager for the Webb Space Telescope. It is his job to make sure the observatory unfolds and extends correctly. He talks us through the deployment sequence in the month after launch. Find out how shake, shimmy and twirl are in the ground controller’s tool box to fix anything that goes wrong.

Spaceflight Now’s Stephen Clark speaks to astronaut, astronomer and former NASA science head, John Grunsfeld about the upcoming launch of the James Webb Space Telescope. What big discoveries is he expecting from JWST? Is he nervous about the complex process to unfold the telescope in space? Why did his efforts to prepare JWST for possible servicing fail?

Astronomers have discovered nearly 5,000 planets orbiting other stars in the last 30 years, and the James Webb Space Telescope will begin scanning a sample of the alien worlds next year to find out which ones might harbor the ingredients for life.

The James Webb Space Telescope, set for launch in the coming days, will look back more than 13.5 billion years in time to see the faint infrared light from the first galaxies, revealing a previously unseen era of cosmic history that shaped the universe of today.

With weather conditions looking favorable for launch Saturday, Arianespace teams in French Guiana transferred an Ariane 5 rocket to its jungle launch complex Thursday with the James Webb Space Telescope.