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For questions concerning electromagnetic radiation in the visible spectrum.

4
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3answers
130 views

Determining the energy efficiency of a Light Wand

So, I'm working out some of the types of wands people can purchase in my flintlock fantasy setting, and I'm having an issue with one of them. Before I get to that, let me explain how Magic in my ...
22
votes
6answers
5k views

What does a solid, 1 mile diameter subterranean glass sphere look like?

There is a solid glass sphere that is 1 mile in diameter. It is completely covered in dirt and rock, except for one small room that is built adjacent to the sphere. One of the four walls of this ...
35
votes
6answers
5k views

What light colors/bulbs should be used inside a spaceship?

I've noticed in recent scifi shows/movies such as the Expanse or Star Trek that the lighting inside spaceships have two characteristics: Punishingly blue lighting Dark/dimmed miscellaneous lighting ...
-3
votes
1answer
191 views

What if light didn't decay by a square law, but instead by an INVERSE square? [closed]

I want to build a character that can control a light source's brightness in different ways. I want to see if instead of proportional to $1/r^2$, my light and darkness controlling character could make ...
6
votes
2answers
104 views

Vision on Titan/Early Earth and the technicalities of a creature seeing in near infrared

I am trying to develop an alien species that could live on Titan and at first I supposed it would be easy with the species being able to use yellow, red and near-infrared wavelengths of light to see. ...
2
votes
2answers
89 views

Albedo of a planet like Crait

If a planet like Crait existed and was covered by (mostly) white sand, what would its average albedo be? Crait is a planet from Star Wars that has a thin layer of white salt on its surface.
2
votes
1answer
122 views

How bright does this planet look from its neighboring planet?

I have two planets that share an orbit around a pair of stars at a distance of 2.05 Earth-AU from the Barycenter of those two stars. (I can provide more details about the two stars, if needed) Using ...
18
votes
5answers
3k views

Can visible light be blocked while still allowing for light for plants to survive to pass through?

What I'm thinking for this question is that some kind of filter is put around the sun by aliens that prevents some kinds of solar energy from passing through but allows other types. Like if it ...
10
votes
4answers
2k views

How do vampires react to passive UV light sources?

Certain fantasy creatures are extremely sensitive to concentrated UV light. eg modern vampires. They either slowly or rapidly burn up in-front of you when exposed to direct sunlight or modern high ...
4
votes
2answers
175 views

Is it possible for a planet with life to orbit around a white hole?

I have created a planet called Betiler. I don't want Betiler to be in a classic space system like a star and some planets. So I put it around a white hole called Phulom. In my world, wormhole doesn't ...
5
votes
3answers
199 views

What would be easy or difficult to do with the power to directly control light?

Without going into too much detail, let's say someone has a superpower which gives them "control" over actual, physical light: Photons, electromagnetic radiation, what have you. This power requires ...
5
votes
1answer
105 views

Can I see my secondary star?

I have a binary star system and have come up with some stats for it. My primary star is an F-type, with a mass of 1.3 sols and a luminosity of 2.197 sols. My secondary star is a K-type, with a mass ...
25
votes
16answers
6k views

How to make sure humans do not know the meteorological phenomenon rainbow?

You've got to love the rainbow, it's an awesome sight. But I don't want humans to have the pleasure of seeing the rainbow. What change to the earth, atmosphere and so on, is needed so that humans ...
5
votes
1answer
285 views

Could a light mage microwave your face?

First post, so I’d appreciate suggestions and help on how to make this question better. Question Suppose there’s a sorcerer with power over light. He can use these abilities to perform all the ...
26
votes
5answers
5k views

How reflective is blood?

If you were on a raft in say, an ocean of blood, and it was very still, would you be able to see the stars of the night sky reflected in it? Would you be able to see your own reflection? How far down ...
9
votes
2answers
490 views

How would sunlight work in the area of shared atmosphere of a Rocheworld?

(See diagram) Presupposing that a Rocheworld can even exist... I imagine that sunlight would work more or less the same in the atmosphere of any part of an Earth like planet that was tidally locked ...
-2
votes
1answer
186 views

How would computer monitors work if we could sense the frequency of light?

Human's abilities to perceive light is quite limited. Essentially, we have three type of light sensors that each give a linear signal, and if two different light sources give the same signals they ...
3
votes
2answers
134 views

How to make glowing rain/mist?

So I've been playing Xenoblade Chronicles 2 and one of the effects that is used through the game (and the series really) is that ether (the game's version of mana) can often be seen floating in the ...
5
votes
3answers
522 views

A double-bright Moon and plant growth

It's Earth and the moon with all parameters as they are in real life with one exception, the moon is twice as reflective as usual. Instead of an albedo of 0.12, the moon has an albedo of 0.24. This ...
-6
votes
4answers
203 views

The Planetary Light Curve

I know that light can be affected by gravity. But what if there was a planet where if you shone a light in a direction and it could hit your back. I'm talking about a planet where light is bent around ...
17
votes
8answers
492 views

Compressed air lighting?

So I've got this civilization that doesn't have electricity, but does have municipal power distribution via compressed air lines. Now, you can do a lot of useful things with compressed air. Even in ...
1
vote
1answer
77 views

What would be more effective for a Shkadov thruster? An entirely white one or a mirror one? [closed]

A Shkadov thruster is a megastructure which reflects all light from a star in a given direction. What reflects more radiation, a white or a mirrored surface?
6
votes
1answer
93 views

Defining the perceived appearance of a moon from a planetary surface

I have a homebrew setting with a moon that has some specific features orbiting an Earth sized planet, and I'm trying to find out how these features would affect how the moon looks from the surface of ...
15
votes
5answers
2k views

How would a microscopic organism create kilometre long fibre optic cables from ice

My story premise is that a human expedition to Europa has happened and the travellers have tunnelled through the ice and formed a colony in the ocean. When they breached into the ocean, they ...
7
votes
5answers
119 views

What traits/actions must give away a light-sensitive out-dimensioner? [closed]

There is a sub-dimension of this reality where a race of humanoid people lives in very low light. Their race has done so for hundreds of years - everyone there has no experience of being outside their ...
-2
votes
1answer
234 views

How would vision be distorted if gravity was 178 000 times higher on earth's surface? [closed]

Ignore any other effect on earth; I'm only curious about how much and in what way gravity's affect on the light would distort what is seen by the eye. :)
0
votes
4answers
168 views

Multiverse Premier League [closed]

My parallel universe has the speed of light set at half that of Earth's (1.5*10^8 m/s). How would a Badminton player (P.V Bindu) from Dearth (my universe) fare against a player (P.V Sindhu) from ...
4
votes
3answers
130 views

Confusing predators with reflected or refracted sunlight

Imagine a large butterfly- or moth-like creature, with a wingspan of about one meter (it's moth-like, not actually related to Earth insects). It lives its entire life high in the open sky, never ...
5
votes
3answers
204 views

Flooding lights

I am designing a world with no sun, there is something similar to asteroids in a nebula, not having a sun means no light so I decided to make that "nebula dust" glow, this dust has the following ...
15
votes
3answers
930 views

How large of a telescope would one need in order to read someone's lips on a planet light years away?

If I wanted to image an Earth-like planet at a resolution where one could read the lips of a human speaking on the surface 1, 10, and 1000 light years away, how large would the telescope reflector ...
4
votes
8answers
2k views

How could there be a horizon on a flat earth?

I'm building a world that happens to be flat. Well, it has hills and mountains, but no curvature. However, I still want to limit the eyesight to a few kilometers even if there are no hills around. I ...
2
votes
3answers
213 views

What are some alternative methods of perception on 'dark' worlds?

For instance; life manages to develop on a planet orbiting a black hole. What are some methods that native life could use for perceiving the environment around them? (e.g. echolocation, sonar, gamma-...
3
votes
2answers
228 views

How to make a planet with differential gravity and constant daylight

I am hoping to create a planet with a greater rotational speed, making it oblong, thus causing differential gravitaion from the equator to the poles. I am hoping for the gravitarion to be lighter than ...
21
votes
5answers
3k views

What are the main problems with beaming light from the Sun to Saturn?

I recently finished reading the Kim Stanley Robinson novel 2312 - set, of course, in the year 2312. Part of the background to the political negotiations and ongoing terraforming in the outer Solar ...
10
votes
4answers
507 views

What could make a star violet?

Part of a series I'm starting since the recent What could make a star green? did quite well and others could use the information here in their worlds. There aren't any "violet" stars. When a star ...
88
votes
9answers
16k views

What could make a star green?

Stars are never green. When a star's spectra "peaks" in the green range, it also releases a significant number of waves of the adjacent colors - so "green" stars appear yellow or white. I want a ...
10
votes
3answers
576 views

Can we identify distinct “colors” beyond visible light?

Let's talk about the visible light "rainbow" In almost all depictions of the electromagnetic spectrum, visible light is shown as a rainbow, and adjacent parts of the spectrum are monotone in color - ...
2
votes
3answers
387 views

Adding mass to light (In laser weaponry) to convert it to kinetic energy

The fictional tech: Lets say I have a crystal, that when a light waves pass through it, imparts some of it's mass onto the light wave. - This is handwave and I'm cool with it. The crystal is ...
1
vote
2answers
293 views

Could a photonic engine actually work?

I have a very specific aesthetic in mind for my science-fantasy setting, technology is largely pneumatipunk supplemented with weired phonotic devices;for "reason" there are few electrical devices in ...
-1
votes
3answers
121 views

scientific explanation for lack of a shadow [closed]

i am curious to know how to scientifically achieve the lack of a shadow for a person. what would have to happen technology wise for a person not to cast a shadow in direct sunlight. i have only ...
13
votes
4answers
5k views

Does mirror armour work against laser guns?

The next war will be fought with lasers beside computers, I'm wondering could a bullet proof vest coated with a highly reflective surface protects user from laser blast. The laser in question is ...
33
votes
8answers
6k views

A monochrome planet

I am asking if a planet with shades of gray only is scientifically possible in our universe. Basically everything on the surface of this planet would seem black and white to the human eye. Here are ...
6
votes
3answers
429 views

Effects of a Moon-sized Sun-Cannon on Earth

Inspired by this answer, If that Lunar-plant is used as a weapon (pointed toward specific cities/forest/seas/lakes), how much damage it could really do? Is that able to burn cities, or anything? I ...
12
votes
4answers
440 views

Would a circumbinary planet have a differently colored sky depending on which star was visible?

One of the things that affects the color of the sky is the wavelengths of light that the star emits, like the image in this question. Here is the image again: If you are standing on a circumbinary ...
9
votes
3answers
720 views

Sky color of an alien world

I'm asking for a world I'm making, which orbits a red star. According to this image, there is a star that would make the sky white. What would the sky look like during sunrise and sunset on a planet ...
3
votes
4answers
478 views

How would gear that could protect from extremely blinding light function?

By 'extremely blinding light', I mean light at least bright enough to blind somebody permanently, and at most bright enough to severely burn humans. What material could be used to construct a helmet ...
5
votes
1answer
349 views

Ultraviolet bioluminescence

Bioluminescence is badass. It involves living beings emitting bright light in the visible spectrum. Would it be, though, possible that a lifeform emits UV (ultraviolet) light? Does it occur in ...
4
votes
1answer
233 views

Light Emitting Animals - What happens to the food chain? [closed]

In my world, an event has happened, some nuclear fall-out caused every animal to grow a special organ that emits light, but I'm wondering what effect that would have on the Food Chain? The world I'm ...
-7
votes
4answers
196 views

How realistic is it to obliterate planet killer with light only?

For this purpose you may make the following assumption: No magic, miracle and hope. The asteroid should be on a collision course for us Threat level is omega. Collateral damage must be keep to ...
2
votes
2answers
207 views

Can a theoretical case be made for “transporting” consciousness via light?

I'd like to develop a baseline of information for pondering this topic: Assumptions I assume that "consciousness" is a definite, precisely-knowable phenomenon. [I recognize that at present we have ...