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Comment by causi | Hacker News Reader

JWST's infrared capability is good at showing previously invisible details but I find it very odd its images keep looking like they're lower resolution and less detailed in the visual spectrum than Hubble images. I realize the observation times are shorter but jeez the JWST photo of Jupiter was garbage compared to a telescope that launched 32 years ago.

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Roughly the angular reolution of a telescope is 1.22*wavelength/diameter. See https://en.wikipedia.org/wiki/Angular_resolution. Hubble uses visual light (0.5 um wavelength) while JWST uses IR (5 um wavelength) and beyond. So the wavelength for JWST is 10x larger than Hibble, but the diameter is only ~2.7X (Hubble 2.4m vs JWST 6.5m dia). So JWST resolution is 1.8x worse than Hubble.

That explains a lot, thank you.

This has been my general feeling, that the JWST photos are less visually interesting/detailed than even Hubble photos. I'm sure they have a ton of invisible data that scientists find invaluable, but they have thus far been largely visually unimpressive.

IMO, the JWST deep field is really impressive. There are something like 4x more galaxies in the background that just were invisible in Hubble due to redshift. JWST is heavily optimized for spectra, far away objects, and looking through gas clouds. For other stuff, you're probably better off using giant ground based telescopes.

The more spectacular Hubble photos are mosaics assembled from weeks or months of observation time. JWST is brand new and has been spending most of its time doing science observations rather than images for the press office. Give it a few years.

Sure, but you can't usefully observe Jupiter for that long, since it rotates.

You can stitch together images taken once per Jupiter day (although you'd lose fine details of weather patterns)

It’s a near infrared telescope, on purpose. Not optimized for non-receding objects.

What photos are these? It has already produced images multiple times more detailed than their Hubble equivalents.

Here's a rando image of Neptune: https://hubblesite.org/contents/media/images/2020/59/4788-Im... I'm certain there are nicer ones. That site has most (all?) of Hubble's images available with keyword search. The reason the rings don't show up is the same reason that Neptune is its real color in the Hubble image. The Hubble image was taken in the visible spectrum, while JWST images are colorized infrared images.

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