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CAPE CANAVERAL, Fla. — The successor to the Hubble Space Telescope is a time travel marvel that can peer into the width of a hair of the dawn of the universe. And finally on the verge of flight.
It will be the largest and most powerful astronomical observatory to leave the planet, detailed in design and ambitious in scope. With a budget in excess of $10 billion, it is the most expensive and also the most difficult to obtain.
Preparing to ascend Friday after years of delay, the James Webb Space Telescope will look for the faint, twinkling light from the first stars and galaxies to provide an insight into cosmic creation. Its infrared eyes will also look into black holes and hunt for alien worlds, scanning the planets’ atmospheres for water and other possible clues to life.
“So it’s worth the risk. It’s worth the pain and sleepless nights,” said Thomas Zurbuchen, NASA’s science mission chief, in an interview with the Associated Press.
NASA Administrator Bill Nelson said he was more nervous than when he launched the space shuttle Columbia in 1986.
“There are over 300 things, any of which have gone wrong, this is not a good day,” Nelson told the AP. “So everything should work perfectly.”
The Webb telescope is so large that it had to be folded origami-style to fit in the nose cone of the European Ariane rocket to take off from the coast of French Guiana in South America. Its light-gathering mirror is the size of several parking lots and its sunshade is the size of a tennis court. Everything has to unfold as the spacecraft sprints toward its perch 1 million miles away.
“We’ve been waiting for this for a long time,” said Sara Seager, planetary hunter at the Massachusetts Institute of Technology. “Webb will push our search for life forward, but we have to be incredibly lucky to find signs of life.”
The 7-tonne James Webb Space Telescope, named after the man who pioneered NASA in the 1960s, is 100 times more powerful than Hubble.
The 31-year-old Hubble – taking increasingly squeaky but still celestial appealing shots – focuses visible and ultraviolet light with just a scattering of infrared light.
As an infrared or heat-sensitive telescope, Webb will see things Hubble can’t, providing “an entirely new perspective on the universe that’s equally awe-inspiring,” said Nikole Lewis, deputy director of the Carl Sagan Institute at Cornell University.
Webb will attempt to look back 13.7 billion years, just 100 million years after the Big Bang that formed the universe as the original stars took shape. Scientists can’t wait to see how closely these early galaxies resemble our present-day Milky Way.
To get rid of Hubble, Webb needs a sizable 21-foot mirror. It also requires a canopy large enough to keep sunlight and even reflections from the Earth and moon away from mirrors and science instruments. The bright, five-layer slender shade stretches 70 feet by 46 feet, necessary to keep all four instruments in a stable sub-zero state—about minus 400 degrees Fahrenheit.
The most daunting part of the mission: Opening Webb’s mirror and sun visor after launch and locking them into the perfect position. The gold-plated mirror consists of 18 motorized parts, each of which must be meticulously aligned so that they can focus in a single way.
NASA has never attempted such a complex set of steps from afar. Many of the mechanisms have no redundancy, so failure of any of these 344 parts could ruin the mission.
After the 1990 takeoff, Hubble suffered its own debacle. A mirror defect was not detected until the first blurry pictures fell from orbit. This blunder led to a series of risky repairs by shuttle astronauts who improved Hubble’s vision and turned the machine into the world’s most successful and beloved observatory.
Webb will be far away for a rescue mission by NASA and its European and Canadian partners.
To prevent a repeat of the Hubble debacle, Zurbuchen ordered an overhaul of Webb in its 20th year of development, after joining NASA in 2016. Northrop Grumman is the main contractor.
The sun visor was torn during an open workout. The tension cables for the canopy were too loose. Dozens of fasteners fell through in a vibration test. All this and more has led to more investigations, more delays and more costs.
Problems continued even after Webb arrived at the South American launch site in October. A clamp loosened and jolted the telescope. The communication relay between the telescope and the rocket has failed.
Now comes the long-awaited departure set at 07:20 EST on Friday, when fewer spectators are expected to travel to French Guiana due to the timing of Christmas Eve.
It will take a full month for Webb to reach his intended parking spot, four times over the moon. From this gravity-balanced, fuel-efficient position, the telescope will keep up with the Earth as it orbits the sun, which is constantly positioned on Earth’s night side.
It will take another five months for Webb to start working by the end of June to cool and control its infrared devices.
The Space Telescope Science Institute in Baltimore operates Hubble and will also oversee Webb. A minimum of five to 10 years of observation is planned.
“Personally, despite all the hype, I think Webb will exceed expectations,” said Ori Fox of the institute, who will use Webb to study supernovas or exploded stars. “Many of what are considered Hubble’s most inspiring discoveries were not part of the original plan.”
Her colleague, Christine Chen, who will focus on budding solar systems, finds solace in Webb’s “perhaps most exciting aspect.” “The universe is weirder and more wonderful than astronomers can imagine.”
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