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According to this article:

https://www.theguardian.com/science/2018/jul/26/star-spotted-speeding-near-milky-way-black-hole-for-first-time

the Very Large Telescope is "powerful enough to see a tennis ball on the moon from Earth". I guess that the moon is much to bright and moves too fast for the VLT to take good pictures of it, but it got me wondering: what is the most magnified picture of the moon ever taken from Earth?

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    $\begingroup$ I assume you mean taken from Earth. Lunar landers will have taken some very close-up photos $\endgroup$ Jul 27 '18 at 11:11
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    $\begingroup$ One further comment. "Most magnified" is not really a helpful way to think of it. If I took a picture with my phone, but then blew up one pixel of it until it was the size of Manhattan, that photo could be very magnified, but it would contain very little detail. What an astronomer would care about is the "highest resolution" photograph (ie the one where the smallest distances on the moon can be distinguished). $\endgroup$ Jul 27 '18 at 14:51
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    $\begingroup$ I'm guessing google.com/moon uses the highest-res images available, so poke around there to see what resolution(s) they're using (they may be using different resolutions for different parts of the moon) $\endgroup$
    – user21
    Jul 27 '18 at 17:34
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    $\begingroup$ However, if you search for "Can we see the Apollo landing sites" then you get the answer no even though many items larger than a tennis ball were left behind. scienceabc.com/eyeopeners/… $\endgroup$
    – badjohn
    Jul 31 '18 at 16:49
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Andrew McCarthy, a Californian stargazer captured a 81-megapixel image (9000px by 9000px) of the Moon and posted it on Redditt. The image was captured using an Orion XT10 telescope, a Skywatcher EQ6-R Pro mount and two cameras: a Sony A7II and a ZWO ASI224MC. The bright half of the moon was processed separately with 25 "tiles" that were stitched together using Photoshop. McCarthy told Forbes:

Each one of these tiles was a 'stack' created using the best 1,000 images taken with the ZWO camera. The stacks were then processed using Autostakkert and the photograph finished on Photoshop.

enter image description here

(The image at 4 different magnifications)

References

  1. https://www.firstpost.com/tech/science/breathtaking-high-resolution-photo-of-the-moon-leaves-reddit-users-crooning-6103661.html
  2. Another high res photo of moon on reddit: https://www.reddit.com/r/space/comments/5tiojb/high_resolution_picture_of_the_moon/
  3. 100-megapixel photo of moon captured by Lunar Reconnaissance Orbiter: https://mymodernmet.com/100-megapixel-moon-photograph/
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  • $\begingroup$ If this is the highest resolution image, can you add what the resolution of the image was? $\endgroup$
    – uhoh
    Aug 2 at 5:05
  • $\begingroup$ @uhoh According to the image author, the image is 9000 px by 9000 px. I don't know if this is the highest res photo of moon captured from Earth, but it is one of the highest res photo captured. $\endgroup$ Aug 2 at 5:54
  • $\begingroup$ That's size or perhaps display resolution but not necessarily actual photographic resolution. Can they resolve 1 arc second? 10 meters on the surface? See en.wikipedia.org/wiki/Optical_resolution $\endgroup$
    – uhoh
    Aug 2 at 5:57
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With lucky imaging, Earth telescopes can achieve a resolution of about 0.1 arcsecond (or about $5×10^{-7}$rad) This is limited by the atmosphere, and having a big, professional telescope actually doesn't help much.

A fact of using lucky imaging is that you don't get the same resolution across the area that you are imaging. Some parts may, by luck, achieve higher resolutions than others.

With 0.1 arcsecond resolution at lunar distance is about 200m. Quite impressive, but a lot larger than a proverbial "tennis ball". The VLT will have been using adaptive optics and working in the infrared (where the twinkling caused by the atmosphere can be compensated for more easily) It is also doing astrometry rather than imaging. It is possible to get sub-arcsecond astrometry even if the source is not fully resolved.

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