Liquid Oxygen - 90 Kelvin

Solid Oxygen - 54.4 Kelvin

Temperature in Space(!) - 2.7-3 Kelvin

https://www.rapidtables.com/convert/temperature/kelvin-to-fahrenheit.html

(!) https://www.scienceabc.com/nature/universe/what-is-the-temperature-of-space.html

(!) https://sciencing.com/temperatures-outer-space-around-earth-20254.html

(!) https://www.allthescience.org/what-is-the-temperature-in-space.htm

Clearly, we can confirm that we live under a dome made out of Oxygen. It is an obvious experiment since everyone believes the Ozone layer, the temperature of space, and you can replicate this one at home, if you are brave enough [it is quite dangerous to handle such low temperature].

This can be further confirmed by additional experiments. For example everyone has been to a mountain and can confirm that the air is hard to breathe there, this is due to the Oxygen being packed with itself, rather than being free in gas state as you have it below the mountain. The more the oxygen is packed with itself, the more you fill your lungs with other atmospheric gases.

Additionally, Ozone turns light blue in liquid form to solid form and becomes semi-transparent. While in cryo-conditions turns to dark blue to violet black. Such is the day sky and night sky showing by simply adding a heat source (below the dome) called the Sun.

"condenses at cryogenic temperatures to a dark blue liquid and finally a violet-black solid." - https://en.wikipedia.org/wiki/Ozone

Everyone has been a globe-earther before they knew the truth, so I would just like to ask people to be more kind to one another. If someone is insulting, beat them with arguments, not more insults.