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GREENBELT, MD - NOVEMBER 02: Engineers and technicians assemble the James Webb Space Telescope ... [+]
With the successful Christmas day launch of NASA’s James Webb Space Telescope (JWST), NASA and its partners have finally secured JWST’s place as a worthy successor to the 30-year-old Hubble space telescope. It should rewrite the history of almost everything we know about the cosmos —- from the universe’s first light to what we know about the outer fringes of our own solar system.
Following six months of commissioning including focusing the mirrors, testing the instruments, calibration, and other operational tasks that need to be verified, NASA expects to have the first science images and spectra from the telescope by next summer, Stefanie Milam, JWST’s Deputy Project Scientist for Planetary Science, told me.
Beyond the early release observations, full science operations will include both data that have no proprietary period (early release science programs as well as some of the Guaranteed time observation programs) that will be released almost immediately, says Milam.
The Webb remains the largest space telescope ever built and its deployable mirror stretches more than 21 feet in diameter, and is composed of 18 hexagonal, gold-plated beryllium mirror segments. But unlike Hubble, it will operate near the Earth–Sun L2 (Lagrange point), a point of gravitational equilibrium, some 1.5 million km beyond earth’s orbit. And unlike Hubble, once the Webb telescope reaches its final observing position at L2, it won’t be able to be serviced.
It’s scheduled for a five-year baseline mission, but NASA reported today that after a very precise launch and the completion of two mid-course trajectory maneuvers, there’s more propellant left than initially envisaged. This should allow for science operations for more than 10 years.
What's the longest JWST could possibly operate?
Once we reach our orbit in L2, we will have a good grasp on the predicted lifetime assuming minimal mechanical issues, says Milam.
One would also hope that as the clock ticks on its nominal 10-year mission, the Webb would be able to extend its operating life via either a robotic or crewed servicing mission. But there’s no official word on that yet.
As for why it took so long to finally see launch?
The mission was originally slated to launch in 2007 was a highly ambitious goal, says Milam. Several technology challenges and developments as well as the extensive and rigorous integration and test program led to multiple unexpected setbacks, she says. Not to mention natural disasters (including a hurricane) and a global pandemic that had to be worked through, she notes.
Even though there were years-long delays, Milam says that the Webb’s detectors were updated in 2015 and have been tested to verify state-of-the art capability. The instruments offer unprecedented capability at near and mid-infrared wavelengths, she says.
Why was JWST such a technical challenge?
“We had to design, build, and fully test a space telescope that was so large it didn’t even fit in a rocket fairing without folding it,” said Milam. “The integration and testing of such large space flight hardware was a major obstacle.” Additionally, light-weighting matter that would perform to the high science standards and capabilities in extreme conditions were another major challenge, she says.
Although NASA deserves congratulations, we need to rethink our whole way of doing astronomy from space. In relative terms, even the Webb’s total cost of $9.66 billion is not a grandiose amount in this age of internet billionaires. Even though NASA is a public agency and the federal government running horrific amounts of budgetary debts, the costs involved for a piece of technology that could change our whole take on the cosmos is a relative bargain.
What does the general public not fully appreciate about JWST?
The number of people working together across the world to design, build, test, and operate this observatory, says Milam. International partners, contractors, even students have all worked as a team to get us to this point, she says.
One can hope that the Webb will offer a sea change in how we view space-based astronomy in order to reprioritize new and future space-based observatories. We need to build even bigger space-based telescopes (or even flotillas of free-flying telescopes in space). But there must be the political will to do so.
Many answers to the fundamental philosophical questions that plague us all are there for the taking. However, it’s up to us to make this technology enough of a priority to transform our cosmic understanding of all that is and all that will ever be.