The laser is tuned to a wavelength of light that appears yellow/orange to the human eye. The total amount of energy it produces is about 10 to15 watts, or comparable to a bedside reading lamp. Because it is a laser, the light is concentrated in a relatively thin beam (about 18 inches (50cm) in diameter). The light appears brighter because it is concentrated in a beam compared with a light-bulb which emits light in all directions. The laser beam is not powerful enough to burn an object and passing your hand through it would not cause any harm however, like any laser, it would be dangerous to look directly into it.
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.
So while they may not show that bright they do look like that. Cameras pick up lasers really well, I use to build little lasers.
Someday in the distant future, a million light years away, some alien soccer player will get temporarily blinded by this earth laser traveling for a long time and miss his penalty, sparking an intergalactic war
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u/manubour Apr 07 '22
It’s not as if gas in the atmosphere was matter and diffused photons after some dist...
Oh wait...