[Firestarter]

NASA's Space Power Facility (SPF), thermal vacuum chamber with a 40 ton, 40 feet diameter door, 122 feet (37 m) high and 100 feet (30 m) in diameter is currently the largest in the world.
It is the updated vacuum chamber that was already in use in 1969.


Strangely no radiation weapons to create sunlight, but instead they use "background heating and cooling", which is fine to make it as cold as space in the shade, but NOT comparable to the intense radiation of the sunlight (not even in the updated chamber in 2022!): https://www.space.com/20535-nasa-vacuum-...scope.html

They would have needed something like the above round door (of course a lot smaller, and turning to the inside) for the lunar module instead of this flimsy hatch.

See the hatch of the 13 Lunar Module turning to the inside.

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There is however another much smaller testing facility that supposedly does simulate the harsh conditions near the sun.
Too small to test the magical space suits, let alone the lunar or main module (and as far as I can tell not in use in 1969): https://www.madeinalabama.com/2016/07/na...e-hazards/