Refresh Rate of Sunlight

Maybe it’s just the warmth from the sun, but I feel good in sunlight. Which got me wondering, what’s the refresh rate of sunlight as it hits the surface of the earth? If people could develop the technology to replicate that refresh rate in a lab, or better yet a living room, would I finally be free of ever needing to go outside to get my Sol good feel?

Rephrase your question. The term “refresh rate” has no meaning as applied to sunlight. Are you just asking about the brightness?

“Refresh rate” is a property of video displays and film projectors, which work by displaying one static image after another. It’s not applicable to a continuous light source like the sun.

Of course sunlight is made up of discrete packets of energy (photons), maybe that’s what you’re referring to? But that’s a function of color and intensity. So if you want to match the number of photons/second in a beam of light, you match the color and intensity of the light. Sunlight can be approximated as a blackbody radiation with approx. 5600K color temperature, and intensity of about 1000 watt per square meter.

Sunlight is a continuous flow of (primarily) visible, ultaviolet (UV), and a small amount of infrared (IR)radiation. Well, technically it comes in small, discrete packets called photons, but for all practal purposes on a macroscopic scale they can be considered continuous. (The linked graphic appears to show that the IR dominates the input, but you should understand that energy increases by an order of magnitude for every decade of increase of frequency or decrease of wavelenght, so most of the energy is actually in the near-UV and UV spectrum.). People have made radiators which approximate the spectral output of the sun, but making it exactly match is complicated and requires many difference individual sources running at different energy levels as the sun radiates as very close to a blackbody, which is then filtered and diffused by the Earth’s atmosphere to produce the light you find so pleasent and refreshing. LED light sources, tuned to produce a similar spectral content, may provide something close to complete sunlight. This is actually a problem for long duration space missions and habitats, as while they are certainly exposed to sunlight the light isn’t filtered as it is on Earth or is at a different intensity, which will require filtering and intensification to replicate the conditions on Earth, and may be a significant contributor to the emotional problems (listlessness, depression, loss of time sense) consistently experienced by astronauts aboard the ISS.

Anyway, you should just go outside. in addition to sunlight you are also getting fresh air and exposure to cycles of daytime which help regulate normal body rythyms rigt down to the cellular level.

Stranger

The radius of the sun is about 700000 km, or more than two light seconds. So if the refresh rate is faster than 0.5 Hz, you wouldn’t actually see the sunlight flicker because the near side will already start getting brighter before the far side (not the actual far side, the farthest still visible part) gets to the dark part of the cycle.

But actually it takes millions of years for the photons to escape from the inside of the sun where they’re created. It would be kind of tricky for a process that takes so long to result in the kind of flicker that you get from AC powered lights. (Ironically LED lights powered by solar cells flicker.)

The thing that you like about daylight is probably the color. It’s easy enough to make the light color look about the same, but you need to match the spectrum in order to make objects of different colors look the same under sunlight and your artificial light. Look for full spectrum lights. (Although the sun isn’t quite full spectrum.)

The 10[SUP]7[/SUP] years estimate for the random walk of photons from the core to the surface of the Sun is a pernicious error that has been much repeated. The actual estimate of the time for a photon created in the core to reach the surface of the Sun is between 10,000 and 190,000 years, based on a weighted 2D random walk Monte Carlo simulation for solar density. The 10My number is apparently based on a mean solar density rather than an accurate model of the density at different radii, which gives an unduly short run length.

Stranger