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Comment by whimsicalism | Hacker News Reader

The telescope photo: https://scx2.b-cdn.net/gfx/news/hires/2024/glimpses-of-a-vol...

Stitched spacecraft photo: https://science.nasa.gov/resource/high-resolution-global-vie...

This seems awesome but I would say 'rival those' is a bit of a stretch

It rivals images from spacecraft in Earth orbit - as in Hubble or Webb. It won’t rival images from cameras sent to the near vicinity of the targets, but those can take decades from the moment you decide to take a picture to the time you take it, unless you already decided you’d take some pictures from that general location decades prior.

>It rivals images from spacecraft in Earth orbit - as in Hubble or Webb. (emphasis mine)

It seems like this critical detail was left out of the headline.

Still technically correct, the best kind of correct. I wonder how much cheaper are land-based telescopes over the lifetime of instruments such as the Hubble or the Webb.

Also, a huge shame the Overwhelmingly Large Telescope was cancelled. We need more creative names for those.

Angular resolution through the Atmosphere has been solved with adaptive optics and advanced mathematical techniques.

Unfortunately, nothing can remove the temperature of the atmosphere (which affects infrared imaging), or the absorption of many wavelength bands.

> I wonder how much cheaper are land-based telescopes over the lifetime of instruments such as the Hubble or the Webb.

10-100 times cheaper. An LBT night is around $50k-100k, which over 10 years corresponds to $300 millions. JWST total budget is about $10 billions.

True, JWST can operate close to 24/7. On the other hand, land-based telescopes are under constant refurbishment and upgrades, and they become more powerful over time.

Sure, but you're comparing apples and oranges. It's like comparing a sports car to a boat. A ground-based telescope can never do what the JWST can do, because of the atmosphere (namely, do IR photography).

Doesn’t change your point, as I believe you are mainly referring to distance from the object being observed. But Webb orbits the sun.

It depends what the parameters for rivalry are .. a ground-based telescope can take multiple photo's, perhaps even thousands, at very low cost - although the resolution may not be comparable, this doesn't discount the value of the data to the scientists who are obtaining it at a far greater reduction of cost and effort than those who rely on space-based instruments. Remember, we don't have a permanent instrument stationed at Io - these spacecraft are doing fly-by's and thus have a limited window of opportunity.

So, while the resolution may be great eye-candy, the consistency of the data over time is vastly different. "Higher resolution" does not always mean "better science", especially if its a one-shot compared to thousands of data-samples...

I was quite taken by the ground-based photo but agree with you upon comparing the links. 50 mile resolution (LBT) vs. 1.6 miles (Galileo) is pretty cut-and-dried. Maybe the point is that LBT can do this for other objects not around Jupiter?

Exactly --- a fly-by of everything in the asteroid belt for example would be a budget-buster --- what is there in the belt which it would be interesting to have photos of?

My high score!! Or we could see which asteroid Han Solo is hiding the Millennium Falcon in. Or we could see all of the illegal mining operations by those pesky guys from Plural Zed Alpha Nine Nine.

We don't know what we won't see until we don't see it.

I agree; I'm thinking that's it's useful to be able to get frequent snapshots of the whole moon at this resolution (if you are interested in time lapse to track volcanic activity for instance). The satellite-based stitched photo probably took a long time to collect.

Also, without knowing details, I suspect you can improve the LBT images as the system matures, but as you say, probably not at the resolution the satellite provides.

That telescope image is the current highest res. Not from the new telescope. That is yet to be released.

Are you sure? The image is captioned:

“Jupiter moon Io, imaged by SHARK-VIS on Jan. 10, 2024. This is the highest resolution image of Io ever obtained by an Earth-based telescope”

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