The James Webb Space Telescope (JWST) has launched into space on Christmas Day.
The most powerful telescope to launch into space, which is on an Ariane 5 rocket, took off from Kourou spaceport in French Guiana at 12.20pm UK time.
The launch was scheduled for Christmas Eve, but a forecast of high-level winds at the spaceport forced it to be postponed until December 25.
JWST follows in the footsteps of the Hubble telescope as the next great space observatory.
A countdown in French was given ahead of the launch, before lift-off was declared.
Controllers had been given a half-hour window to get the Ariane 5 rocket carrying the telescope airborne, and successfully targeted the beginning of the time period.
Designed to answer unsolved questions about the universe, the telescope will look further back in time than ever before to 400 million years after the Big Bang, the UK Space Agency has said.
The event was livestreamed on the Nasa website.
As the rocket launched, Nasa spokesman Rob Navias said: “Lift-off, from a tropical rainforest to the edge of time itself, James Webb begins a voyage back to the birth of the universe.”
The telescope could reveal the existence of extra-terrestrial life forms in space, a scientist who helped to develop the observatory has said.
Martin Barstow, professor of astrophysics and space science at the University of Leicester, has worked in the mission’s operations centre for the past seven years.
He said: “We will learn about the origins of the universe and how life came about and possibly, although we can’t guarantee, about other life in our galaxy as well.”
The observatory is equipped with cameras capable of taking images from other planets which will show the presence of elements and molecules in the atmosphere, he said.
Scientists can then scan the images for the possible existence of cells and evidence of different life forms.
“We are standing at the beginning of a new era in astronomy. The telescope is that important that its going to completely change the way we view the universe and the way we view our place in it,” Prof Barstow said.
The JWST, which is the most powerful telescope ever to launch into space, is finally set to lift off on Christmas Day after further delays caused by bad weather.
Designed to make ground-breaking discoveries in astronomy, it follows in the footsteps of the Hubble telescope as the next great space observatory.
Development for the telescope began in 1996 and construction was completed in 2016, with the launch initially planned for the beginning of December 2021.
A number of setbacks including a communications issue and an incident requiring an extra round of checks on the telescope pushed the date back.
The JWST’s partners are the European Space Agency (ESA), Nasa and the Canadian Space Agency (CSA) – but many scientists from universities across the UK, including Durham and Leicester, have contributed to the project.
The space agencies have now completed a readiness review for the rocket and launch teams, having conducted their final rehearsal.
For those who have worked on the telescope over the past two decades, its launch on Christmas Day will be a climactic event, Prof Barstow said.
“I’m excited but frightened about it too,” he added.
“The Ariane 5 rocket is very reliable but no rocket is 100% perfect so there’s always that nervousness when you see 20-plus years of planning, building and development on top of basically what is a giant firework,” he said.
“If I’m perfectly honest I’ll probably be eating Christmas dinner while we’re watching it, biting my nails.”