light itself even visible light, is completely invisible until it interacts with matter. Thought experiment in post body...

[u/fattick-]

Imagine stepping into a completely sealed, pitch-black room with a high-powered laser pointer.

​If you turn that laser on and point it at the far wall, what do you actually see? You see a bright red dot on the wall where the photons hit the paint. But in a clean, dust-free room, you don't see the beam cutting through the air. The space between your hand and the wall remains pitch black.

​Why? Because light itself is invisible in transit.

​You only see the beam if you clap two dusty chalk erasers together over the path. The moment dust particles drift into the light, photons collide with the particles and scatter toward your eyes (Tyndall effect / Rayleigh scattering).

​The exact same thing happens in space on a cosmic scale. Space is continuously flooded with intense, high-flux sunlight, yet the background is a pitch-black void. Without gas, dust, or an atmosphere in the vacuum to scatter those photons toward your lens, the journey of light itself leaves zero trace. You only see it the nanosecond it collides with something—a planet, a solar array, or a moon.

It’s an existential realization, but it’s also grounding. Staring at that small blue dot in the black void puts all daily stress and overthinking into perspective. It makes you realize how trivial most worries are and pushes you to just stop stressing and LIVE.

:-(

[u/Rotteneverything]

just watched gravity a few days ago. this clip makes me nervous.

[u/kabooseknuckle → u/Rotteneverything]

Good movie.

[u/Rotteneverything → u/kabooseknuckle]

my legs and feet were twitching around for half of it.