On January 4, local time in the United States, the official website of the National Aeronautics and Space Administration (NASA) released the news that the James Webb Space Telescope team has fully unfolded the spacecraft's 70-foot-long (about 21.336 meters) visor, which is an important milestone since the Launch of the Webb Telescope.
On December 28, 2021, three days after the Launch of the Webb Telescope aboard Europe's Ariane 5 rocket, the entire team began remotely deploying visors.
The visor is the size of a tennis court, and since no rocket launcher can currently carry this huge visor, the visor must be folded at launch to accommodate the payload area of the Ariane 5 rocket. Therefore, the successful deployment of the sun visor in space has also become a key step in the normal operation of the Webb telescope in space in the future.
Image from NASA
Nasa held a media conference call on the afternoon of January 4, EST, to discuss the completion of this milestone.
"This is the first time someone has tried to send such a huge telescope into space." Thomas Zurbuchen, deputy director of the Science Mission Directorate at NASA headquarters in Washington, said, "The Weber telescope needs to be carefully assembled not only, but also carefully deployed. Its most challenging deployment, the successful deployment of the visor, is a testament to human ingenuity and engineering that will allow Weber to further achieve its scientific goals. ”
This five-layered visor will protect the Webb telescope from the solar heat of the Sun, Earth and Moon. Each layer of plastic visor is coated with reflective metal, which provides protection with a sun protection factor of more than 1 million. These five layers are stacked together to reduce solar exposure of more than 200 kilowatts to less than 1 watt.
The protection of the visor will help keep Weber's scientific instruments at minus 228.89 degrees Celsius, a low temperature that allows Weber to observe faint infrared light from distant objects.
"Opening Weber's visor in space is an incredible milestone that is critical to the success of the mission as a whole," said Gregory L. Robinson, Weber's program director at NASA headquarters. The team accomplished the bold feat of this complex task — one of Weber's boldest missions to date. ”
The world's largest and most complex space telescope has five and a half months to go, including the deployment of the secondary mirror and main mirror wing, the calibration of the telescope's optical system, and the calibration of other scientific instruments. After that, the Webb telescope will release to Earth the first images it acquires in space.