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GMoromisato ◴[] No.44401068[source]
In case anyone is wondering, we are (sadly) very far from getting an image of this planet (or any extra-solar planet) that is more than 1 pixel across.

At 110 light-years distance you would need a telescope ~450 kilometers across to image this planet at 100x100 pixel resolution--about the size of a small icon. That is a physical limit based on the wavelength of light.

The best we could do is build a space-based optical interferometer with two nodes 450 kilometers apart, but synchronized to 1 wavelength. That's a really tough engineering challenge.

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GolfPopper ◴[] No.44401398[source]
We can do better than that! Using the Sun as a gravitation lens[1], and a probe at a focal point of 542 AU, we could get 25km scale surface resolution on a planet 98 ly away. [2] This would be an immense and time-consuming endeavor, but does seem to be within humanity's current technological capabilities.

1. https://en.wikipedia.org/wiki/Solar_gravitational_lens

2. https://www.nasa.gov/general/direct-multipixel-imaging-and-s...

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ycui1986 ◴[] No.44402383[source]
There are also alternative proposals to use Earth's atmosphere refraction for focusing, in a geometrically similar fashion as gravitational lens. It seems more feasible than using Sun's gravitational lensing.

https://en.wikipedia.org/wiki/Terrestrial_atmospheric_lens

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1. Intralexical ◴[] No.44409646[source]
Has anyone explored using the target planet's mechanical motion? As it rotates and orbits, a different part of it will be lit up every hour (and every season). You only get a single pixel at once, but that pixel is localized to a region that scans across the whole surface over time.

For something Earth-like, I think you could definitely make out the Americas, Asia, and probably Africa. Maybe both of the ice caps too, depending how it's oriented and if you're capturing spectra. ...Somebody should mock up a solver in Python.

I'm sure there are other tricks you could use. Diffraction limit schmraction schmidit, real planets aren't point light sources.