After two decades, the Webb telescope is finished and on the way to its launch site
A ship carrying the $10 billion James Webb Space Telescope left a port in Southern California last weekend to begin a nearly two-week journey to Kourou, French Guiana, where it will begin final preparations for launch Dec. 18 on a European Ariane 5 rocket.
“The James Webb Space Telescope is finished,” said Paul Hertz, head of NASA’s astrophysics division, in a presentation to the Astronomy and Astrophysics Advisory Committee earlier this week. “We’ve stopped working on it. It’s on the way to the launch pad for a launch on Dec. 18.”
Eric Smith, NASA’s program scientist for the Webb telescope, confirmed Wednesday the observatory has departed the United States after completing final testing at a Northrop Grumman facility in Redondo Beach, California.
“We are in transit to Kourou, having left the continental United States now,” Smith said in the advisory committee meeting.
NASA is keeping specific schedule details about the observatory’s journey under wraps for security reasons. The vessel carrying the Webb telescope will traverse the Panama Canal to cross from the Pacific Ocean to the Caribbean Sea, then complete the voyage to Kourou, French Guiana.
Smith said mission managers have 13 days of schedule margin to have Webb ready for launch Dec. 18. Liftoff is scheduled in the mid-morning, local time, in French Guiana.
Besides the hands-on work on Webb itself, Smith said NASA and ESA will closely watch the launch of an Ariane 5 rocket next month with an SES commercial communications satellite and a French military spacecraft. Webb’s launch date of Dec. 18 hinges a successful outcome of that mission.
The shipment of the Webb telescope to French Guiana follows a series of tests at Northrop Grumman to ensure the spacecraft can withstand the rigors of launch. The testing subjected the observatory to the vibrations and sound energy it will see inside the payload shroud of its Ariane 5 launcher.
Then engineers performed final tests to unfurl the observatory’s mirrors and sunshield, checking that the deployment mechanisms are ready to go. It was the last time Webb’s components will deploy into flight configuration before liftoff.
With those tests complete, crews at Northrop Grumman folded up the observatory and put it in a climate-controlled shipping container for the trip to French Guiana.
Webb, a successor to the Hubble Space Telescope, is a joint project between NASA, the European Space Agency, and the Canadian Space Agency. The observatory’s total cost is near $10 billion, making Webb the most expensive and complex science mission ever launched.
Design work on Webb began in the 1990s, and NASA awarded a contract to Northrop Grumman in 2002 to oversee construction of the observatory. With the shipment of Webb to Kourou, the project is in the home stretch before launch.
One of ESA’s contributions is the Ariane 5 rocket that will launch Webb toward its operating post nearly a million miles (1.5 million kilometers) from Earth.
After launch, the observatory will begin a make-or-break sequence of deployments to extend its solar array, high-gain antenna, and mirror segments. Webb also has a five-layer sunshield to shade its mirrors, detectors and science instruments, keeping the telescope colder than minus 370 degrees Fahrenheit, or minus 223 degrees Celsius.
Made of aluminum-coated Kapton, each sunshield layer is as thin as a human hair. The sunshade will expand to the size of a tennis court once Webb is in space.
The observatory’s infrared instruments will peer into the oldest, most distant reaches of the universe to study some of the first stars and galaxies that formed after the Big Bang more than 13.5 billion years ago.
Astronomers will also use Webb to look at how galaxies form and evolve, to study the birth of stars, and to learn more about the atmospheres of planets that may be hospitable for life outside our solar system.
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