"Resolution" also depends on the wavelength of the camera. A mono camera will have 90% QE at 400nm, so that's probably a better number for wavelength. So to "resolve" that angular separation, I get 16.9 meters. The math looks like this:
But what does that really mean…to "resolve"?
It means that if you observed or took a picture of two point objects of equal brightness separated by the diameter of Sirius, they would not get swallowed into a single Airy disk. Instead, they would form an oblong of two Airy disks.
Forming an image of a disk is a very different task than "resolving" two points. For instance, your eye pupil can "resolve" 67 arcseconds in daylight and 27 arcseconds fully dark adapted (at 533 nm). Jupiter is typically in the 40 arcsec range. But can you make out Jupiter's disk? Nope.
A better reference is how they got that recent picture of that black hole the size of Mercury's orbit at 27,000 light years distance. They used a resolution 6 times smaller than the target to form an image of 3 blurry blobs on a ring. And to get details on Jupiter, I use an aperture with a "resolution" 50 times smaller than Jupiter's disk.
So multiply your estimate by 10 to 100. You'd probably need the better part of 200 meters of aperture. And a good Strehl ratio. Somewhere on the moon.
Edited by BQ Octantis, 23 May 2022 - 06:28 PM.