The first JWST images are in and I need a minute

The JWST sent back its first images and I need a minute.

They’re alignment images. Calibration data. Eighteen separate pictures of the same star, one for each mirror segment, used by the STScI team to figure out how to bring the mirror into focus. This is the telescope equivalent of tuning an instrument before a concert.

And they’re already staggering.

In the background of a calibration image, behind the star being used for alignment, you can see galaxies. Dozens of them. Tiny smudges of light that didn’t show up in previous infrared telescopes. They’re just there, accidentally, in the background of a test.

The full science images don’t come until June.

What we’re looking at

Each of the 18 mirror segments captured its own version of the star HD 84406. The images are slightly offset from each other because the segments aren’t aligned yet. Over the coming weeks, the team will nudge each segment with its actuators, a fraction of the width of a human hair at a time, until all 18 images merge into one.

The precision required is absurd. Each segment can be adjusted in seven degrees of freedom. The actuators operate at -233 degrees Celsius. The target alignment is 150 nanometers, roughly the size of a coronavirus particle.

I keep thinking about the people who built these actuators. Someone at Northrop Grumman or Ball Aerospace designed a mechanism that needed to work perfectly, in the cold vacuum of space, 1.5 million kilometers from the nearest repair shop. There’s no Hubble-style fix this time. No spacewalk. If an actuator fails, that segment is done.

So far, they all work.

The background galaxies

This is the part that broke me a little.

The calibration images aren’t pointed at anything interesting. HD 84406 was chosen specifically because it’s an unremarkable star in Ursa Major. Boring. Safe. Good for alignment math.

But even in a boring patch of sky, JWST sees things we’ve never seen before. Galaxies that were invisible to Hubble’s infrared. Faint, distant objects that were below the detection threshold of every previous telescope.

If the background of a calibration image looks like this, what will the actual deep field images look like?

I don’t think I’m ready.

Five more months

June. The ESA and NASA teams will release the first full-color science images sometime in June. The targets haven’t been announced. Could be a nebula. Could be an exoplanet atmosphere. Could be the deepest view of the early universe we’ve ever captured.

I’ll be refreshing the webpage when they drop, same as I refreshed the deployment tracker on Christmas. Some things in this life are worth being obsessive about.

The telescope is working. The mirrors are aligning. The universe is waiting.

I’m trying to be patient. I’m not succeeding.

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