Two of the three main pieces that make up the world’s next most powerful space telescope were just integrated into one massive, shiny, strange assemblage in Redondo Beach.
The custom-designed James Webb Space Telescope’s 72-foot-long sun shield was married this week to the self-propelling robotic “bus” that will carry it 1 million miles beyond Earth, according to officials from Northrop Grumman Corp.’s Space Park facility near the beach.
“This is a huge milestone for the Webb telescope as we prepare for launch,” said Jim Flynn, Webb sun shield manager for Northrop Grumman Aerospace Systems. “The groundbreaking, tennis-court size sun shield will protect the optics from heat, making it possible to gather images of the formation of stars and galaxies more than 13.5 billion years ago.”
The self-propelling robotic bus also holds Webb’s electronics, communications systems, thermal control devices and propulsion equipment.
When the scope’s 21-foot-tall, gold-plated mirror is connected later this year, the complete apparatus will go through months more testing before launch in October 2018.
Webb’s mission is to retrieve the first glimpses of the galaxies and star clusters that emerged from the Big Bang 13.7 billion years ago. It’s a nearly $9 billion joint project of NASA, the European Space Agency and the Canadian Space Agency that is scheduled to blast off in October 2018 on an Ariane 5 heavy-lift launcher.
It will try to answer questions about how planets are born and, ultimately, how life emerged.
“Maybe on some deep level, we know that we’re connected to the universe. We know that when we look up at the universe that, in a sense, we’re looking back at ourselves,” NASA astrophysicist Amber Straughn said in a March public lecture about the project. “We’re looking back at our origins of where we came from.”
Big footsteps to fill
Webb’s predecessor, the Hubble Space Telescope, has captured photos of celestial bodies 13.2 billion light years away during its 27-year orbital history.
But the new telescope—named for the space science pioneer who led NASA during the 1960s — will see farther than ever before using infrared rather than optical light that the human eye can see.
Unlike Hubble, James Webb won’t orbit Earth about 300 miles above. It will park at a relatively stable far-out spot 1 million miles away called the second Lagrange point and search for the first signs of planetary bodies in the universe.
“What could possibly follow up the amazing science Hubble’s given us?” Straughn said. “That, of course, is the James Webb Space Telescope. And I truly believe that this telescope will be a worthy successor to Hubble.”
Once Webb is launched, it will take about two weeks to reach its destination.
There, the sun shield will unfold like a giant robotic parasol.
Made of five thin Kapton membranes that are coated in shiny aluminum and silicon, it’s designed to keep heat from the sun, Earth, moon and electronics in the bus away from Webb’s delicate mirrors and science instruments.
The shield’s plastic-like layers, which have special seams to limit damage from meteors, are now being tediously folded into long, aerodynamic, wing-like appendages, officials said.
They must keep away even the slightest warmth from reaching the delicate mirrors.
“All five sun shield membranes have been installed and will be folded over the next few weeks,” said Paul Geithner, deputy project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
The telescope’s 21-foot-tall mirror and camera equipment are in Houston for deep-freeze testing until November. They’ve been lying inside a giant, specially built cryogenic chamber at NASA’s Johnson Space Center since July.
Before that, the mirror went through a prior round of deep-freeze testing at NASA’s Goddard Space Flight Center in Maryland.
When the optics equipment return to the South Bay later this year, the whole assemblage will be integrated with the sun shield and bus and tested as a single unit.
The beryllium mirror, made up of 18 hexagonal plates coated in gold, must remain at a deep-space chill so the scope’s infrared imaging isn’t disturbed.
Like the sun shield, the mirror will be folded compactly inside the rocket and will unfurl robotically in deep space.
The heat-sensitive equipment will be kept stable in a vacuum-sealed chamber during launch. It was subjected to the extreme noise and vibrations of launch during tests in March.
“One of the reasons we test the telescope so much is because this is hard,” Straughn said. “Make no mistake about it, this is really difficult. This is coming up to the edge of impossible engineering.”