Webb Slips Again — Now Eyeing a December Launch
NASA's James Webb Space Telescope has slid to a November-December launch window, the latest delay in a saga that's been going on for years.
If you’ve been following the James Webb Space Telescope for any length of time, you already know the drill: another year, another slip. The latest word out of NASA is that Webb is now targeting a launch window somewhere between November and December of this year, riding an Ariane 5 rocket out of French Guiana. That’s still months away, and given the mission’s track record, I wouldn’t be shocked if the date moves once more before liftoff actually happens.
For anyone who hasn’t been tracking this since the beginning, a quick refresher on just how long this has been going: Webb was originally supposed to fly back in 2018. That’s not a typo. Three years and counting of delays, and this telescope has become something of a running joke among space reporters — the observatory that’s always “a couple years out.”
To be fair, the reasons behind the delays aren’t frivolous. Webb isn’t a simple satellite you bolt onto a rocket and send up. It’s an enormous, fantastically complex piece of engineering: a 6.5-meter segmented gold-coated mirror that has to unfold in space, a tennis-court-sized sunshield with five layers that also has to unfurl perfectly, and instruments that need to be cooled to near absolute zero to do their job. None of that has ever been built before, at this scale, for a mission with this much riding on it. Every fold, every deployment mechanism, every joint has to work exactly right the first time, because Webb isn’t going to a serviceable orbit like Hubble was. It’s headed to the second Lagrange point, roughly a million miles from Earth — well beyond the reach of any rescue mission.
That distance is exactly why NASA has been so cautious about locking in a date and then blowing past it repeatedly. A telescope like this doesn’t get a do-over. If something goes wrong during that sunshield deployment or mirror unfolding sequence, there’s no shuttle crew flying out to fix it the way astronauts serviced Hubble multiple times. So every schedule slip, frustrating as it is for those of us who’ve been waiting years to see first light data, is presumably in service of not rushing a one-shot deployment sequence that has to nail dozens of steps in a row.
Still, waiting is waiting, and it’s hard not to feel a little numb to yet another date change at this point. The scientific case for Webb hasn’t gotten any less exciting in the meantime — infrared observations of the earliest galaxies, atmospheric analysis of exoplanets, a deeper look at star formation than Hubble could ever manage. If November or December holds, we’ll finally get to see whether all that engineering caution pays off. Until then, it’s one more entry in the long list of “coming soon” for a telescope that’s been coming soon for years. I’ll believe the launch date when the rocket’s on the pad.