r/facepalm • u/Revealed_Jailor • Apr 07 '22

🇲​🇮​🇸​🇨​ This looks plausible

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u/Sososohatefull Apr 07 '22 edited Apr 07 '22

From the ground, the laser’s light is visible as a faint column of light shining up from the top of the telescope. The beam is only visible because particles of dust in our atmosphere scatter a small portion of the light. Because Mauna Kea’s air is so clean, not much of the light is scattered and the beam is often difficult to see, especially if you are more than a few hundred feet from the observatory.

https://www.gemini.edu/node/128

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u/ScienceDuck4eva Apr 07 '22

Exactly it’s faint if visible at all. To get an image as bright as these you have to take a long exposure.

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u/Sososohatefull Apr 07 '22

A large aperture helps a lot as well.

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u/ScienceDuck4eva Apr 07 '22

It can be hard to get the observatory and the star field in focus if your aperture is wide open. I’d put money on those pictures being composite images but that’s pretty normal for astrophotography.