Celebrating two years since JWST launched
22 Dec 2023



We relive the successful launch of this amazing space mission on Christmas Day 2021.

A rocket, carrying the James Webb Space Telescope, photographed during launch.



The James Webb Space Telescope launched on 25 December, 2021. The rockets on the European Space Agency's Arianne 5 powering JWST through the cloud cover in French Guiana, up through the atmosphere and into space.

The culmination of decades of research and work at UK ATC, STFC and RAL Space​ alongside scientists, engineers, technicians, astronomers, organisations and universities across the world.

​UK ATC played a major role on MIRI one of the four main science instruments on board. MIRI was designed, built, and tested by a European Consortium of 10 member countries led by the UK, in partnership with the US. The European contribution was led by UK ATC Director Professor Gillian Wright CBE.

The launch went exactly as planned. At an altitude of 870 miles, Webb separated from the Ariane 5 rocket. A few minutes later Webb's solar array unfolded and mission managers confirmed that the solar array was providing power to the observatory. Twelve hours later the first mid-course correction took place firing Webb's thrusters to correct its trajectory toward its destination in orbit about 1 million miles from Earth.

The precision of the Arianespace Ariane 5 launch exceeded expectations so less propellant was used than anticipated on the mid-course correction, meaning Webb has more fuel than expected extending its lifetime in space.

Professor Gillian Wright, European Principal Investigator for MIRI and Director of UK ATC, said at the time: “To see Webb launch, with MIRI on board, after more than two decades is a seminal moment.

“MIRI is a special instrument, for the breadth of its science, the team that built it, and being the coolest instrument on Webb. The MIRI team rose to the challenges and brought some exquisite engineering solutions to make it a reality.

“The Webb mission as a whole is an amazing technological breakthrough in scale and complexity, and this extends to the instruments, including MIRI. With the launch, all of us are excitedly anticipating the first MIRI data and the new view of the universe we will have."

Since launch JWST and MIRI have been opening up new areas of scientific study, expanding our understanding of the Universe and providing some amazing images of the cosmos.