NASA’s $10 billion James Webb Space Telescope will study the universe’s origins

For the past 31 years the Hubble Space Telescope has been an invaluably versatile observation platform for astronomers but it’s begun showing its age of late. Last serviced in 2009, the telescope has had to enter the partial-shutdown “safe mode” multiple times over the last few years — most recently, this October. And while optimistic estimates suggest that the Hubble could remain in operation through the end of the decade, NASA, with its ESA and CSA partners, have already spent more than a dozen years developing a successor, the James Webb Space Telescope (JWST). When the Webb launches — currently set for liftoff on Christmas Day — it will take over as humanity’s preeminent eye in the sky for decades to come.

The 7.2-ton JWST will be the largest telescope NASA has ever put into orbit. Its 6.5-meter primary mirror array — composed of 18 gold-plated hexagonal segments — is more than twice the size of the Hubble’s and nearly 60 times larger in area than the Spitzer Telescope, which retired in 2020. The sun shield it uses to protect its delicate infrared sensors is nearly as long as a tennis court, and …read more