«The opening of the sunvisor into space is an incredible milestone, and critical to mission success,» Gregory L. Robinson, Web Program Manager at NASA Headquarters, said in a statement. «Thousands of parts had to meticulously work in order for this engineering marvel to fully unfold. The team accomplished a daring feat with the complexity of this deployment — one of the boldest tasks yet for Webb.»
It’s one of the toughest spacecraft deployments NASA has ever attempted, according to the agency.
An oversized five-layer sun visor will protect Webb’s giant mirror and instruments from the sun’s heat. The mirror and instruments must be kept at an extremely cold minus 370 degrees Fahrenheit (minus 188 degrees Celsius) to be able to observe the universe as designed. Each of the five sheets is as thin as a human hair and coated with reflective metal.
When Webb was launched, the sun visor folded over to fit inside the Ariane 5 rocket that carried the telescope into space. The eight-day operation to loosen and tighten the protective shield began on December 28. This involved opening the support structure of the shield over a period of several days before each layer began to be stretched or stretched.
The fifth layer of sun visor was tightened and secured in place Tuesday at 11:59 a.m. ET.
Overall, the entire process, which was controlled by teams on the ground, involved perfect and coordinated movement of hundreds of release mechanisms, hinges, sawing actuators, pulleys and cables.
«The film-tensioning phase for sunvisor deployment is particularly challenging because there are complex interactions between the structures, tension mechanisms, cables and membranes,» James Cooper, director of NASA’s Web Shield, which is based at Goddard Space Flight Center, said in a statement. . «This was the hardest part of testing on Earth, so it’s great that things are going well today.»
Teams work in 12-hour shifts to make sure everything runs smoothly with Webb’s deployments.
With the sunvisor in place successfully, Webb project manager Bill Ochs said the telescope has overcome a 70% to 75% probability of more than 300 single-point failures that could disrupt its ability to operate.
Jim Flynn, Sunshield manager at Northrop Grumman, NASA’s principal contractor for Webb, said in a statement.
The telescope has the ability to look back in time, using infrared observations to reveal otherwise unseen aspects and to look deeper into the universe than ever before.
«This is the first time anyone has attempted to put a telescope of this size into space,» Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate, said in a statement. «Webb required not only careful assembly, but also precise diffusions. The success of his most challenging publication — the Sunscreen — is an incredible testament to the human ingenuity and engineering skill that will enable Webb to achieve his scientific goals.»
What will come next
Webb is expected to take about 29 days to reach its intended orbit a million miles from Earth, with other important steps along the way — and that includes another big challenge later this week: opening the telescope’s mirror.
The mirror can extend 21 feet 4 inches (6.5 meters) — an enormous length that allows it to collect more light from objects once the telescope is in space. The more light the mirror can collect, the more detail the telescope can observe.
It’s the largest mirror NASA has ever built, but its size created a unique problem. The mirror was too big for a missile. Engineers designed the telescope as a series of moving parts that could fold origami and fit into a 16-foot (5-meter) launch space.
Finally, Webb will make another trajectory modification to insert himself into an orbit beyond the Moon.
While that takes 29 days, the telescope will go through an operating period in space lasting about five and a half months, which includes cooling, aligning and calibrating its instruments. All tools will also go through a logout process to see how they work.
Webb will begin collecting the data and its first images later in 2022, expected to be released in June or July, forever changing the way we see and understand the universe.
