The telescope, which is worth £6.5billion, has been successfully tested in anticipation of its launch in 2019.
Engineers working on the project are confident it will be able to capture starlight in focus and track astronomical targets.
The James Webb telescope has been described as a ‘time machine’ that could help unravel the secrets of our universe.
The telescope will be used to look back to the first galaxies born in the early universe more than 13.5billion years ago, and observe the sources of stars, exoplanets, and even the moons and planets of our solar system.
When it is launched in 2019, it will be the world’s biggest and most powerful telescope, capable of peering back 200 million years after the Big Bang.
Mark Voyton, the manager for the Optical Telescope Element and Integrated Science Instrument Module said: “We’re extremely elated to be here, especially after the successful completion of our cryovacuum and optical testing of the world’s most magnificent time machine, the Webb telescope.”
The telescope went through 100 days of cryogenic testing where temperatures were as low as hundreds of degrees below the freezing point, which ensured it can function in extreme cold.
According to NASA, to detect infrared light from objects far away, the telescope must be kept very cold.
The James Webb Telescope and most of its instruments have an operating temperature of roughly minus 387 Fahrenheit.
This instrument uses a cryocooler to keep it below minus 447 degrees Fahrenheit.
When it launches, Webb will be the largest space telescope in the world.
During additional tests last year, the 18 gold primary mirror segments were tested as well, to ensure they act as a single mirror.
The test even managed to continue as Hurricane Harvey hit the Texas coast.
Jonathan Homan, project manager for Webb’s Chamber A test team at Johnson said during the time, Hurricane Harvey hit “the telescope did not know, the chamber did not know that there was an event going on outside its environment.
“We had spent probably more than a month to get the chamber and the telescope down to test temperatures, and we were ready for testing — it was a primary part of optical testing.
“It maintained [its minimum temperature], held those conditions without any incident. With that, that meant that helium refrigerators were operating, cryogenic liquid nitrogen systems were operating, vacuum systems were operating, lots of telemetry, data systems, control systems were operating,” although the building “took some water hits.”
He said although the storm was much fiercer than expected and the Johnson and Goddard teams had planned well enough that they were able to keep personnel and hardware safe and avoid any interruption to testing. And afterward, he and others added, many of the Webb team volunteered in the community to help Houston recover.
The team began to warm the chamber back up on September 27, before pumping air back in.
Then, on November 18, they unsealed the door.
Source : EXPRESS