James Webb Space Telescope reaches launch pad for Christmas liftoff
The James Webb Space Telescope is due to launch on Saturday (Dec. 25) during a 32-minute window that opens at 7:20 a.m. EST (1220 GMT). The massive observatory will blast off from Kourou, French Guiana, atop an Ariane 5 rocket operated by European launch provider Arianespace. You can watch launch coverage live at Space.com beginning at 6 a.m. EST (1100 GMT) courtesy of NASA or you can watch directly at the agency's website.
ESA launch kit (PDF).
*SPOILER* (click to show)
*SPOILER* (click to hide)
Space science: The telescope that ate astronomyJWST Primary Mirror Starting To Come TogetherNew Space Telescope's Giant Gold Mirror Unveiled (April 29th)Telescope That 'Ate Astronomy' Is on Track to Surpass HubbleJames Webb Space Telescope Vibration Testing CompletedLaunch of James Webb Space Telescope Delayed to Spring 2019Launch of James Webb Space Telescope Could be Further DelayedJWST: Too Big to Fail?GAO: James Webb Space Telescope Launch Date Likely Will be Delayed (Again)Launch of James Webb Space Telescope Delayed to May 2020, Could Exceed Budget CapNASA Announces JWST Independent Review Board MembersScrews and Washers Have Fallen Off JWST Amid Testing and Independent ReviewLaunch of James Webb Space Telescope Delayed Again, This Time to March 2021, Cost at $9.66 BillionNASA Administrator at House Hearing: WFIRST Could be Delayed to Help Pay for JWSTJames Webb Passes Critical Mission Review for 2021 Launch, Final Testing Nearing CompletionNASA Ominously Chooses Halloween 2021 to Launch Long-Delayed Space TelescopeThe James Webb Space Telescope, NASA's Next Great Observatory, Passes Final Ground TestsThe James Webb Telescope has a Launch DateNASA's James Webb Space Telescope Passes Crucial Launch-Simulation TestsJames Webb Telescope: Preparations Resume for December 22 LaunchNASA's James Webb Space Telescope Fully Fueled for Launch
It's 300 and something. Most of them are related to the deployment, but a few are part of the actual science stuff.
It might work, but if they each have a 0.2% chance of failure, the overall system is still just a coin flip. To get actual good odds you need four or five nines on them all. Assuming the rocket doesn't blow up.
James Webb Has 344 Single-Point Failures. Here Are the 5 Most Critical Elements [interestingengineering.com]
If it does fail, space telescope development needs a reality check.