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NASAs James Webb Space Telescope launches in French Guiana

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BALTIMORE - NASAs revolutionary James Webb Space Telescope is hurtling away from Earth and toward deep space on a long-awaited, high-risk mission that, if successful, will look deeper into the cosmic past than any telescope before.

The Webb blasted off Christmas morning from the European Space Agency's spaceport in Kourou, French Guiana, on South America's northeast coast, and early reports from NASA suggest the mission is going swimmingly.

This is, however, an unusually difficult mission involving an extraordinarily complicated instrument, and in the coming days and weeks the telescope will have to transform itself through a series of hardware deployments, each of which is critical to the telescope's ambitious astronomy.

Though relieved by the successful launch, NASA deputy administrator Pam Melroy acknowledged what everyone involved with the Webb knows: "We have some scary days ahead."

That NASA chose to forge ahead with a Christmas launch was a sign of how seriously the agency and the global scientific community takes this $10 billion mission, the long-delayed successor to the Hubble Space Telescope. Officials had challenging discussions about launching on a holiday, and amid the rapid spread of the omicron coronavirus variant but decided to go on the first possible day, which after two technical problems and one weather delay turned out to be Dec. 25.

Melroy put a positive spin on it: "It's not bad that it's happening on Christmas Day, which should be a day of hope and inspiration."

The telescope left Earth in a folded position, fully enveloped in the cone of Arianespace's heavy-lift Ariane 5 rocket, which rolled to the launchpad Thursday. Less than half an hour after launch, it separated from the final booster and was traveling at 22,000 miles per hour, "flying on its own in coast phase," as NASA put it.

Early reports indicated that everything was "nominal" - precisely the space-jargon term that the thousands of people who have worked on the mission were hoping to hear on launch day.

"It was a perfect ride to orbit," announced Rob Navias, NASA's launch commentator.

The separation from the final booster provided a stunning - and, for humanity, probably the final - view of the Webb. A camera on the upper stage of the rocket captured the rear end of the Webb receding, with the Earth on the right side of the frame. Then came a critical deployment - solar arrays jutting from the spacecraft, gleaming brilliantly in full sun and ensuring the telescope will have power out there in the void.

"There it is. There is your critical call. James Webb not only has legs, it has power," Navias said. "Quite a Christmas present for the world's astronomers."

At a news conference in Kourou after the successful launch, NASA science chief Thomas Zurbuchen highlighted that image of the telescope receding into space: "For me that picture will be burned into my mind forever."

The launch and the deployment of the solar arrays was greeted with cheers at the Space Telescope Science Institute in Baltimore, where officials, industry executives and a smattering of journalists gathered in the institute's auditorium to watch events on a big screen. Upstairs, in the high-security Mission Operations Center - which took over the mission after the launch team in French Guiana concluded its task - the outcry of joy among the engineers and technicians was intense enough to send a rumble through the building.

"My feet have stopped tapping," planetary astronomer Heidi Hammel, who could not bear to sit down during the launch, said in the institute cafeteria as the Webb flew through space. "It's all calming down now, and I'm starting to breathe normally."

More drama is coming, though.

"I want to hear that the covers open on the sun shield and then that the sun shield starts to deploy properly," Hammel said. And then there's the less-heralded "secondary mirror," which has to protrude properly to bounce light from the telescope's main mirror down through the center of the telescope.

"The secondary mirror has to deploy, otherwise there's nothing," Hammel said.

The launch date had been Dec. 18, but a technical mishap at the spaceport - a large clamp coming loose and jostling the telescope - required a four-day delay to ensure that nothing had been damaged. Another glitch with an essential cable delayed the launch for two days, to Dec. 24. Then came the one-day weather delay. Christmas morning dawned cloudy but without storms, and the launch proceeded without a hitch, at 9:20 a.m. local time in Kourou - 7:20 a.m. in Baltimore.

The predawn streets and elevated highways of Baltimore were empty, but by 6 a.m. the Space Telescope Science Institute was bustling. Some news media and scientists dropped out in recent days as the omicron variant spread, and so the hoopla was limited. Visitors were handed KN95 masks and told to take rapid coronavirus tests.

Saturday morning's prelaunch event at the institute began with remarks by Webb team members, including representatives of Europe's and Canada's space agencies, partners in the mission. The speakers emphasized the telescope's potential to answer fundamental questions about the history of the cosmos.

"Look farther, delve deeper and measure more precisely, and you're bound to detect something new and wondrous," said Kenneth Sembach, director of the telescope institute. "It is a gift to everyone who contemplates the vastness of the universe."

Melroy echoed that: "When we see things with a new lens, we gain new knowledge and new perspectives that can change fundamentally how we see the universe and how we see ourselves."

The rocket will send the telescope far beyond Earth's gravity well, and into a gravitationally stable position known as L2, where the telescope will orbit the sun and remain roughly a million miles from Earth on the opposite side of our planet from the sun.

The journey to L2 will take about 29 days. Along the way, the Webb will undergo course corrections and a series of critically important deployments of its hardware, including a sun shield the size of a tennis court.

After the sun shield opens up, NASA will send a command from Earth to unfold 18 gold-plated, hexagonal mirrors, which together will function as a 21-meter light bucket, nearly three times the diameter of the Hubble's mirror.

This is a novel design, driven by ambitious scientific objectives.

NASA and its partners must overcome 344 potential single point failures, according to an independent review board. That list began with launch, although the Ariane 5 has an excellent track record.

Zurbuchen, who was in French Guiana for the launch, said last month that the agency has tested the telescope and its instruments thoroughly.

"We've gone through every systematic analysis that we can think of," he said.

The Webb, named for NASA's administrator at the height of the 1960s Space Race, traces its scientific roots to the 1980s, and has been under development since the mid-1990s. It has struggled through multiple delays, and survived one congressional attempt to terminate the mission as its cost soared.

"It's been a long road, as many of you know, to get where we are. Even so, we planned such a revolutionary telescope that it has stood the test of this time," Hammel said Thursday during a NASA science webinar on the goals on the mission.

The Webb is an infrared telescope, capturing wavelengths outside the spectral range of the Hubble Space Telescope. With the sprawling sun shield protecting it from the sun's heat, and with additional help from cooling devices, the Webb will take advantage of extremely cold temperatures, below minus-370 degrees Fahrenheit.

It is designed to see the oldest stars in the universe and scrutinize the formation of the earliest galaxies. It will also study the atmospheres of exoplanets that orbit stars in our galaxy.

It can even look at nearby neighbors, such as Jupiter - where scientists still want to know why the Great Red Spot on the planet is red, Hammel said. Two other targets are Jupiter's intriguing moon Europa and Saturn's moon Enceladus, both of which have geysers believed to signal the presence of subsurface oceans.

"If we can put our beam there and detect organics in this plume material that may give us clues to the habitability of subsurface oceans," Hammel said.

It will take about six months for NASA and its partners to fully commission the telescope and begin delivering the promised images from deep space. In addition to the well-publicized challenges of deploying the sun shield and the mirrors, the spacecraft has to cool itself to extremely low temperatures. The individual mirrors can be adjusted to achieve the kind of resolution that should make the Webb roughly 100 times more powerful than the Hubble.

So a lot of work is still ahead - but Saturday was a giant leap for a telescope that at times looked like it might never get off the ground.

"Tens of thousands of people have committed over 20 years or more on a single project," Matt Mountain, an astronomer who is part of the team that designed the telescope, said at the telescope institute just minutes before launch Saturday. "And why? Why have they committed this time? We solve incredibly hard problems. It's part of the human spirit. We're curious. We explore."

Published : December 26, 2021

By : The Washington Post