Northrop Grumman has announced that James Webb Space Telescope has successfully cleared launch stress tests in preparation for its launch in 2021.

The tests involved a series of post-test checkouts and deployments, as well as the five-layer sunshield deployment exercise.

Northrop Grumman James Webb Space Telescope vice-president and programme manager Scott Willoughby said: “The Northrop Grumman and Nasa team has further validated that the James Webb Space Telescope can communicate and deploy as we have rehearsed in simulations, after launch.

“This milestone has given us an unprecedented and breathtaking view of the near-fully deployed observatory. I am looking forward to the team’s continued achievements as we march down our path towards launch and mission success.”

The five-layer sunshield is designed to safeguard the observatory’s mirrors and scientific instruments from light and heat.

Webb’s optics and sensors are required to remain extremely cold because the telescope is infrared light optimised. The sunshield plays a major role to regulate the temperature.

The sunshield comprises of a polymer material called Kapton and each of the five layers is covered with vapour-deposited aluminium. This enables the shield to reflect the Sun’s heat into space.

Nasa Webb Telescope sunshield manager James Cooper said: “This was the first time that the sunshield has been deployed and tensioned by the spacecraft electronics and with the telescope present above it.

“The deployment is visually stunning as a result, and it was challenging to accomplish.”

The observatory will now undergo comprehensive electrical tests and mechanical tests followed by final deployment and stowing cycle on the ground.

The Nasa’s James Webb Space Telescope was successfully assembled by Northrop Grumman in August.

The project is led by Nasa with its partners, the European Space Agency and the Canadian Space Agency.