On Christmas Day, 2021, astronomy forever changed with JWST’s launch.
By mid-2022, a fully calibrated JWST unveiled its first science images.
Its images were sharp, pristine, beautiful, and unprecedentedly informative.
But in some sense, they were almost too good.
JWST’s views were sharper, with less noise, than anyone had predicted.
The key was understanding why, so this unprecedented success could be repeated.
Although JWST displays many remarkable improvements, one advance was critical.
Sure, the instruments are astoundingly good, with near-perfect photon efficiency.
The pointing and guiding system, as well as signal throughput, are performing optimally.
The telescope is kept sufficiently cold; thermal emission and instrument noise are negligible.
Additionally, the optics are so good that stray light — normally problematic — is negligible.
But JWST’s biggest advance is in controlling its PSF: point spread function.
JWST focuses its light better than any space-based or ground-based telescope ever.
Why? Because — from mirrors to instruments — it was kept cleaner than any observatory ever.
Advances in clean-room technology and handling enabled a PSF twice as sharp as required.
As a result, JWST science is more informative than anyone expected.
With the fuel saved from a near-perfect launch, JWST should remain operating so pristinely through 2044.
Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.