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Help with characteristics of my fictional planet

ClearDragon

Troubadour
I haven't been here in a while, but I'm back now.
Anyway I need some advice about my fictional planet.
The planet is about the same size as earth, but has drastically different geology. Most notably is a vastly much greater amount of quartz. My idea behind this was that the properties of quartz crystals under pressure in the planets interior would generate a much stronger magnetic field, that possibly would decay much slower than earth's.
Next the planet has a higher percentage of oxygen in the atmosphere and higher atmospheric pressure. My idea being that the plants and animals can be bigger.
Also there would be more carbon dioxide and water vapor in the the atmosphere. Idea being the sky might be pale green and no ice caps at the poles. This should also mean warmer temperatures, so reptiles and amphibians would be bigger. Now I want a more exotic feel to the place, so I was thinking of the planet orbiting a blue sun. Not a giant, but just a pure hydrogen star about the size of our sun. I assumed this would make the plants different colors.
But just what colors? I've been looking this up and it seems to range from orange to blue.
Now there is a little problem. I've got 3d models of trees and plants that will be in my stories, so if I've been wrong about the colors I have to recreate them all!
So what I'm asking is does this make sense? Have I put it together ok, or misunderstood things?
 
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CupofJoe

Myth Weaver
It sound okay to me...
If you want it to be scientifically accurate, then you have a LOT of work ahead of you tracking down experts that can and will give you the answers. And don't be surprised if the answer is "I have no idea".
On the other hand...
Not many people seemed to have stopped watching Avatar because it may have been scientifically a bit iffy.
And I don't know anyone that has stopped reading Sir Terry Pratchett because a Discworld on top of four Elephants on top of a space swimming Turtle is unscientific.*
Narrativium and Handwavium can make almost anything believable as long as it fits the story and doesn't contradict what you have already established.
If your plants are orange and blue, then a green tree will be noticeable and noted... and there would have to be a reason for it.
* Okay there are probably someone out there that has done one or both of theses things, but really do you want those people reading your stories? ;)
 
My idea behind this was that the properties of quartz crystals under pressure in the planets interior would generate a much stronger magnetic field,
I'm not an expert on quartz crystals, but I don't think they impact a magnetic field. They have no magnetic properties (they're not a metal and all that). Earth has a magnetic field because we have an iron core which moves. To make it stronger you either need more iron or make it move faster.

Idea being the sky might be pale green
Our sky is mainly blue because blue light scatters more (because it has the shortest wavelength) then other colors, not so much because of the different gasses that make up the atmosphere.

I was thinking of the planet orbiting a blue sun. Not a giant, but just a pure hydrogen star about the size of our sun.
the color of a star is only caused by its size. To get a blue star you need a bigger star because bigger stars burn hotter. Which means you probably want to move the planet further out. Note that this also gives your star a shorter life than a yellow star, so if you need evolution and a few billion years then you'd run into issues time-wise.
Also, if you have a pure hydrogen star (though as soon as the star stars burning you start making helium and then other elements) then you wouldn't have planets. To get a pure hydrogen star you can only have hydrogen around, which means that there's no other materials around to make a planet from.

Plants would indeed match their color to make most use of the star's light. Which takes more likely to be different colors. Though note that on earth we also have differently colored plants in some places with specific circumstances (like coral which can be red because red light can more easily penetrate into the water).

I agree with CupofJoe that some Handwavium can help you get away with a lot, and actually with more than if you try to explain it. I have no problems accepting Discworld because it's clearly not scientific. However, the things I mentioned here trigger me because you attempt to explain them and they go against my knowledge. Which then pulls me out of a story as being unbelievable.
 

Yora

Maester
Fantasy or sci-fi?
Are the characters of the story native to the planet or alien explorers. If they are native, their eyes would have evolved to deal with the light conditions and see colors in whatever way you want.

Plants could be any color. The only color for alien plants that would probably be predetermined is black plants for very faint red stars because they will need to get any light they can, including infrared. Yellow, white, and blue stars have such intense light that the plants can pick just part of the light and reflect whatever colors they want.
Green plants on Earth are actually the most inefficient color to get energy from the sun. Purple would be best, or alternatively red or blue. Green reflects the most energetic parts of sunlight and absorbs only the weak parts.

Astronomically speaking, blue stars have to be giant. And they don't really look blue to the human eye because there's still so much red and yellow that they max out all human color perception making it appear white. But again, that depends on how the eyes of the native creatures evolved.

I don't think a stronger magnetic field would have any real impact on anything, except that the planet might have no polar lights.

If it's fantasy, you can just make up whatever you want and say the physical parameters are whatever is needed to get thia result. Fantasy characters are unlikely to ever talk about the geological history of their planet or the chemistry of their star.
 

ClearDragon

Troubadour
I see, this is pretty interesting.
Now as for my stories, in the backstory the star and actually the whole solar system are artificial.
I forgot to mention that. I thought that since the star was created from collected pure hydrogen, it would be hotter and tinted blue even if it was sun sized.
I really like the idea of purple, red and blue plants!
What I was looking for is a reasonable explanation for why a sun sized star could be blue, even if it doesn't exist in the universe, just as long as it was reasonably possible.
 

ClearDragon

Troubadour
Hey people, I just found this interesting page A-Type Stars
An A type star is perfect, they can be only twice the mass of the sun and a blue-white color.
A planet at maybe 4.6 to 5 AU from the tar would be easily habitable. There would be higher ultraviolet radiation, which would also be good for bigger reptiles. Also plants grow bigger under blue light, so my trees can reasonably be taller than on earth and different colored.
I think a star class of A5V would be perfect. How does that sound?
 
I'd say go for it. You might want to factor in that species would be able to see ultraviolet light if there's that much of it.

In the end, I think Yora has a question whether you're writing fantasy or sci-fi. Fantasy you can get away with most things. Sci-fi might need some more explaining. Though I'd guess that The Hitchhickers guide to the galaxy would have gotten away with just handwaving it.

Also, as the hitchhickers guide points out, space is really, mindbogglingly big. Within the realms of physics most things you can come up with will exist somewhere. Especially if you go with "the whole thing was engineered"
 

ClearDragon

Troubadour
I'd say go for it. You might want to factor in that species would be able to see ultraviolet light if there's that much of it.

In the end, I think Yora has a question whether you're writing fantasy or sci-fi. Fantasy you can get away with most things. Sci-fi might need some more explaining. Though I'd guess that The Hitchhickers guide to the galaxy would have gotten away with just handwaving it.

Also, as the hitchhickers guide points out, space is really, mindbogglingly big. Within the realms of physics most things you can come up with will exist somewhere. Especially if you go with "the whole thing was engineered"

Yeah, I'm going to! What I'm writing is basically science fantasy, but I don't want it to be too far out so there are certain things that are supposed be pretty realistic. So an A type star could be perfect, now I just need to figure out it's specification. A light blue star not too many times bigger then the sun would be good. I'm thinking type A6V?
 

K.S. Crooks

Maester
The colour of a star is caused by its temperature not its size. Now yes blue stars are super giants because they have the greatest amount of gravity to make nuclear fusion run hottest and fastest. Stars this large die off the fastest and are considered too short lived to have life as we know it( they last only millions of years not billions). There are also red giants. These are stars in the beginning of their death phase. Our sun will become a red giant in about 5 billion years, give or take a few days. Our sun will grow to a diameter of between the Earth's and Mars' orbits.

Our star is yellow, however the light is white (all colours). Plants are a certain colour denoting the wavelength of light they use the least. They reflect the unused light, which we see. If a plant is orange it means it uses orange light less and other colours more. This is why there are green maples and red maples; they use different chlorophyll pigments.

All-in-all write your story the way you want. If you want a blue star, purple sky and orange plants simply do so. No one will question why, unless you make those seem odd and not the norm.
 
I think this is one of those situations where the more you explain the more eyebrows you raise.

If you want your flora to have a particular hue, just do it - don't try to rationalise and above all don't try to justify scientifically. You only have to get one thing wrong and it jolts the reader out of their suspended disbelief.
 

ClearDragon

Troubadour
I think this is one of those situations where the more you explain the more eyebrows you raise.

If you want your flora to have a particular hue, just do it - don't try to rationalise and above all don't try to justify scientifically. You only have to get one thing wrong and it jolts the reader out of their suspended disbelief.

I think thats some wisdom there! I honestly would not have thought of it, I would have kept trying to figure out ways it could have happened.
So I think I will just have a quick reasonable explanation, and not go into any detail.
 
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