A bit of a science question.

[Gryphon]

So there's a scene in my book I'm writing where the main crew goes to the big bad's lair. The catch is the big bad's lair is a giant tower that turns everything a hundred miles away from it from night to day.

Light is also how we see color. The peel of an apple is red because the red wavelength in light reflects off the peel while everything else passes through. The reason the sky is blue is because blue wavelengths of light scatter more than the other colors, turning the sky blue during the day while at night, without light, wee see the sky as it truly is. Pretty much just space.

So, for a cool visual, I'm wanting to describe the light from the tower turning the sky from above it blue while everything else is the natural space since the scene takes place at night. Clouds are pretty much unable to be seen until they cross the line into the blue spot in the sky caused by the tower's light.

What I'm wondering is if that would make since scientifically. I don't see any issue in it myself, but I'm not exactly a light expert. I know the basics of light and color, but not the nuances. Anyone with more understanding of this than me here that can tell me if I'm overthinking or if it would just turn the sky blue.

 

[Corty]

You are overthinking it. If its believeable enough for your story and your previous settings/events in the the story, it should be good.

Those who would go on a rant on how light breaks apart when hitting the water particles in clouds and so they would look like this and this and you have written it Incorrectly, etc…. They need help and not your attention.

 

[M.G.Driver]

Light doesn't pass through opaque objects, so your example of an apple is wrong (unless it was a transparent red apple).

It sounds feasible, but your big bad tower would have to emit a sort of special fog that reflects only blue wavelengths downwards. This is assuming your tower is lower than the lower atmosphere boundary. You need a way of controlling that special fog as well to limit the radius to a hundred miles, else wind patterns and rotation of the planet is going to screw with it. Maybe magnetic fields on 'handwavium' particles?

If your tower is higher, then you could probably just emit sunlight in a directional cone. This won't get you the sudden change from night to day though, it would be gradual like a terminator line.

 

[Deleted member 54065]

The principles of light as we know it apply only if you wanted your setting to be on Earth, or similar to Earth. If you're working on a fantastical setting, even a scientific one, you can make your own rules, though to make it believable it needs to have a sliver of earth science in it.

Still, as an author, you call the shots. For example, my story's got a scene there where it's raining, yet the people standing under the rain doesn't get wet, though the ground is. I wrote that in passing, just to show that the world I created is fundamentally different from the principles of physics, as we know it here on Earth.

 

[Syringe]

I think you're overthinking it. Unless your story is Sci-Fi and heavily grounded in reality, then I wouldn't worry about molecular physics and interactions too hard. Magic > Physics. If it's not Earth and it's a fantasy setting, then do what you want. Don't let real life logic detract from a cool scene. Make it as wonderful as you want!

What's physics to magic?

 

[Gryphon]

Light doesn't pass through opaque objects, so your example of an apple is wrong (unless it was a transparent red apple).

Well I've always just been taught as it passing through if it doesn't bounce off. Though I'm pretty sure that might have been just to make it more simple to understand, maybe. Or the teachers I had just didn't teach well. Or maybe both

It sounds feasible, but your big bad tower would have to emit a sort of special fog that reflects only blue wavelengths downwards. This is assuming your tower is lower than the lower atmosphere boundary. You need a way of controlling that special fog as well to limit the radius to a hundred miles, else wind patterns and rotation of the planet is going to screw with it. Maybe magnetic fields on 'handwavium' particles?

If your tower is higher, then you could probably just emit sunlight in a directional cone. This won't get you the sudden change from night to day though, it would be gradual like a terminator line.

Basically, the tower is a tower of light. I guess I should have made that more obvious. The antagonist takes the light from all over the universe, and combines it into that one big tower. No stars shine in the night sky. Fire no longer shines, and the sun is constantly dim. So, if I were to make the tower high enough to reach into space so that light goes downward into the atmosphere, would that work?

The principles of light as we know it apply only if you wanted your setting to be on Earth, or similar to Earth. If you're working on a fantastical setting, even a scientific one, you can make your own rules, though to make it believable it needs to have a sliver of earth science in it.

Still, as an author, you call the shots. For example, my story's got a scene there where it's raining, yet the people standing under the rain doesn't get wet, though the ground is. I wrote that in passing, just to show that the world I created is fundamentally different from the principles of physics, as we know it here on Earth.

Well, although my book is high fantasy, I still like to keep my worlds feeling as realistic as possible. There are certain readers that could get turned off if everything is out of nowhere BS that makes no sense in a real world perspective. I'm not that hard on stuff like realism myself, but I do like to implement it when necessary.

 

[M.G.Driver]

Basically, the tower is a tower of light. I guess I should have made that more obvious. The antagonist takes the light from all over the universe, and combines it into that one big tower. No stars shine in the night sky. Fire no longer shines, and the sun is constantly dim. So, if I were to make the tower high enough to reach into space so that light goes downward into the atmosphere, would that work?

If it's a tower of pure light from the ground to reach into space(100km), I think the sky will not be blue - it would be like a brightly lit city at night, creating a sort of blurry white haze over the place. This is because I believe the lower (30km) part of the tower would have a larger surface area than the top (it's not a pillar right?) Therefore the light below the atmosphere will be more than above.

If the tower's main light source is at the top instead of the bottom (e.g bottom is dimmer than the top, say 60% of all radiation comes from the top etc) you still need to find a way to angle the light downwards (i'm currently thinking of a cone, so the light shines outwards rather than down into the atmosphere.

Unless your tower also increases the refractory index of the air around to cause light to bend at 90 degrees down to the surface(certain angles require more than that - it's a cone). But usually those kind of refractory index implies that the air around is effectively solid to have such an index.

 

[melchi]

Well I've always just been taught as it passing through if it doesn't bounce off. Though I'm pretty sure that might have been just to make it more simple to understand, maybe. Or the teachers I had just didn't teach well. Or maybe both

Basically, the tower is a tower of light. I guess I should have made that more obvious. The antagonist takes the light from all over the universe, and combines it into that one big tower. No stars shine in the night sky. Fire no longer shines, and the sun is constantly dim. So, if I were to make the tower high enough to reach into space so that light goes downward into the atmosphere, would that work?

Well, although my book is high fantasy, I still like to keep my worlds feeling as realistic as possible. There are certain readers that could get turned off if everything is out of nowhere BS that makes no sense in a real world perspective. I'm not that hard on stuff like realism myself, but I do like to implement it when necessary.

To be honest, I wouldn't notice if the sky was blue around the light tower or if it just looked like a giant bonfire. The shorter wavelengths of light scatter against the nitrogen from what I understand. Also, if the sun is constantly dim it begs the question of what wavelengths the sun is emitting. If there were more lower wavelengths they the sky could be violet as well.

 

[Ilikewaterkusa]

So there's a scene in my book I'm writing where the main crew goes to the big bad's lair. The catch is the big bad's lair is a giant tower that turns everything a hundred miles away from it from night to day.

Light is also how we see color. The peel of an apple is red because the red wavelength in light reflects off the peel while everything else passes through. The reason the sky is blue is because blue wavelengths of light scatter more than the other colors, turning the sky blue during the day while at night, without light, wee see the sky as it truly is. Pretty much just space.

So, for a cool visual, I'm wanting to describe the light from the tower turning the sky from above it blue while everything else is the natural space since the scene takes place at night. Clouds are pretty much unable to be seen until they cross the line into the blue spot in the sky caused by the tower's light.

What I'm wondering is if that would make since scientifically. I don't see any issue in it myself, but I'm not exactly a light expert. I know the basics of light and color, but not the nuances. Anyone with more understanding of this than me here that can tell me if I'm overthinking or if it would just turn the sky blue.

Most readers won’t care about light nuances