Most of what you see here will be unfolded in the weeks to months after launch.
There have been years of delays in construction and a few late slips in the launch schedule, with the latest being a short delay due to bad weather at the South American launch site. The launch of the James Webb Space Telescope is less than 24 hours away. It's hard to believe it's actually happening.
Tomorrow will see the telescope sent on its way to the L2 Lagrange point with its solar panels and its main communication antenna unfolded. The telescope's sun screen will be extended and the telescope itself will be unfurled in the next weeks. We can't be sure that the hardware will live up to its promise until there are multiple failures.
NASA has a complete six months between launch and operations that you can use if you want.
If you want to watch the launch itself, NASA TV coverage starts at 6 am US Eastern time tomorrow morning, and we've embedded the NASA TV stream immediately below. Ars will be taking a break from its usual holiday drinking and sleep schedule in order to be at the Space Telescope Science Institute for the launch, so expect a report from there later in the day.
