The James Webb Space Telescope is about to

The James Webb Space Telescope launches in five days.

I’m terrified.

Not figuratively. Not in the “oh, I hope it works” way you might be worried about a friend’s job interview. Genuinely anxious. I’ve been reading about the deployment sequence and my hands are cold and my stomach hurts.

Let me explain.

The numbers

$10 billion. That’s the cost. Spread over 25 years of development, testing, delays, redesigns, more testing, and more delays. Originally supposed to launch in 2007. Then 2011. Then 2014. Then 2018. Then 2020. Now 2021.

Every delay was a chance to make it better, more reliable, more tested. NASA Goddard, ESA, Northrop Grumman, and a thousand engineers across multiple countries spent a quarter century on this machine.

And in five days, they’re putting it on top of an Ariane 5 rocket and launching it to a point 1.5 million kilometers from Earth.

No repair missions. Hubble orbits 547 km above Earth. We sent astronauts to fix it five times. JWST will be 1.5 million km away. If something breaks, it’s over.

The 344 points of failure

JWST is too large to fit inside any rocket fairing. It had to be designed to fold up. Like origami. A telescope made of origami.

The primary mirror is 6.5 meters across, made of 18 hexagonal gold-coated beryllium segments. They fold for launch and deploy in space. Each segment has actuators that position it with nanometer precision.

The sunshield is the size of a tennis court. Five layers of kapton, each thinner than a human hair. It folds into a tight package for launch and unfolds over the course of days. The unfurling involves 107 release mechanisms, 8 deployment motors, and hundreds of cables and pulleys.

344 individual mechanisms need to work in the correct sequence over a two-week period after launch. Not one of them has a backup. If any single mechanism fails, the telescope might not deploy correctly, and at 1.5 million km from Earth, nobody is going to fix it.

344 single points of failure. In space. $10 billion. 25 years.

Why I care this much

I’ve been following JWST since I was in school. It’s been a background constant in my awareness of space science. “Webb will launch soon” has been a running joke in the astronomy community for over a decade.

But it’s not a joke anymore. It’s real. The telescope is in French Guiana. It’s been loaded onto the rocket. The countdown is ticking.

When it works (I’m choosing to say when, not if, because I need the optimism right now), it’ll be the most powerful space telescope ever built. It sees in infrared, which means it can look through dust clouds that block visible light. It can see the first galaxies that formed after the Big Bang. It can analyze the atmospheres of exoplanets for signs of water, methane, and other molecules that might indicate life.

JWST isn’t just a telescope. It’s a time machine. It sees light that has been traveling for billions of years. The images it sends back will show the universe as it was when it was young. Before our Sun existed. Before the Milky Way took its current shape.

We’re about to see the childhood of the cosmos.

If the 344 mechanisms work.

The wait

I’ve set alarms. Launch is December 25th. Christmas morning. I’ll be watching the NASA livestream with coffee and anxiety.

After launch, the deployment takes about two weeks. The sunshield unfolds first (days 3-6). The secondary mirror extends (day 10). The primary mirror segments unfold (days 12-13). Then months of cooling, alignment, and calibration.

The deployment tracker will update in real time. I’ve bookmarked it. I’ll be checking it hourly. Maybe more than hourly.

I haven’t been this nervous about a machine since my first server deployment. Which seems embarrassingly small in comparison. My server was hosting a website. This machine is going to look at the beginning of time.

Five days.

Please work. Please, please work.

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