Sky colour

[David Evil Overlord]

Plant colour would also be affected by the different light. It is green on Earth as it makes the best of the light from our sun, (help from biology bods please) it could be a much darker green or possibly red, I think I have heard the Earth was covered in red bacteria for a while.

For binary stars: http://www.cosmosmagazine.com/node/4243

For single stars with different wavelengths of light form Sol: http://www.cosmosmagazine.com/news/1160/nasa-predicts-colour-alien-plants

And that research brings up another question or two, Warren. Is your planet's star single or binary? And if binary, how do the two different star's light/colour mix when both are in the sky?

You might have your blue sky while one star is up, and a different colour when both are above the horizon. Again, I'm awaiting a real scientist to tell me why I'm wrong, but it's an idea.

P.S. This was the story that inspired my comment above about higher gravity/thicker atmosphere. The scientists speculate about elephant-sized fliers on such worlds...

http://www.cosmosmagazine.com/node/3615/full

 

[Warren_Paul]

I was originally going with a single star, but binary gives me ideas too. It reminds me of the movie "Pitch Black". I believe that planet had 3 stars didn't it? I'll have to check it out again, don't remember the sky colour on the planet.

 

[David Evil Overlord]

Or, you could go with this:

http://www.cosmosmagazine.com/news/5326/new-class-extrasolar-planet-a-waterworld

An exoplanet that might just be a hot and steamy waterworld.

 

[Glitch]

If your planet was actually a moon orbiting a large gas giant, could that giant have an effect on the moons sky colour?

Would a large orange gas giant give the moon an orange tint ?

 

[Warren_Paul]

Or, you could go with this:

http://www.cosmosmagazine.com/news/5326/new-class-extrasolar-planet-a-waterworld

An exoplanet that might just be a hot and steamy waterworld.

That's a good find, David.

230 degrees Celsius

- Apart from the burning to death bit...

will have to move the planet back a bit I think. Surprised to see they actually found a planet out there that might possibly support the theory of a water vapor canopy. Wonder if moving the planet would effect it, but then, this is such an unknown that not even educated readers would be refute the possibility.

Hot ice... interesting.

Oh and, after checking out trailers/screens of Pitch Black - Don't have the movie to actually watch at the moment - I believe the sunlight was almost florescent bright at points, the sky either white or brown/orange. - So multiple suns might work as well.

 

[David Evil Overlord]

One of the (many, too many!) stories I'm working on has a species of sentient alien adapted for high temperatures (not quite 230 degrees Celsius, but still...).

They are quite amazed to find our kind of life, where they always thought it was too cold for any life forms to exist.

 

[Bowler1]

Thank you Evil Overlord, the links posted were very informative and something I have been wondering about. My plants will now vary in colour. Life form convergence I think will hold, still lots of scope for fun there. Nice one guys.

 

[David Evil Overlord]

Glad to help you with your alien gardening, Bowler1.

 

[TheDustyZebra]

I don't know anything about the sky color stuff, but I wonder if you might be better off dealing with it as a biological problem rather than an astronomical one? The color of the sky is what our eyes make of it, after all. Scientists claim that various animals see in black and white, or varying degrees of the colors that people see, and then there are all the different types of color-blindness among people. Nothing looks precisely the same color to any two people, even if they aren't "color blind" as such. Your people could easily have some eyeball setup that makes the sky look purple, or red, or green, or whatever. It could be a different color to visiting aliens, if there were any.

 

[Warren_Paul]

Thanks guys, I think I'm going to take the multiple sun approach, that way I can time their passage through the sky so that the rayleigh scattering is like a sunset almost the whole time. It will also help contribute to the dry arid state of the planet. There will have to be a little bit of blue at one point of the day, but I could work that in to great effect.

I will also have longer days as a consequence.

 

[Glitch]

I think I'm going to take the multiple sun approach, that way I can time their passage through the sky so that the rayleigh scattering is like a sunset almost the whole time.

Doesn't that mean certain parts of the planet will be in constant daylight ?

Depending how you orbit the suns you can also have constant darkness. Might give you a small habitable zone in the twilight you seek.

 

[David Evil Overlord]

I thought of that for one world I created (and haven't written a story about). A world where a fierce blue star faced a world with orbit and rotation matching, so the same side always faced the sun. The habitable zone for humans was the twilight region, not too irradiated, not too eternal darkness.

The obvious name for the planet was Twilight. But a certain teenage vampire series ruined that for me, now didn't it?

 

[Ursa major]

I was about to ask WP if there were sparkly vampires on his world.


By the way, how close are these various suns to the planet and to each other? And perhaps it's just as well the place is arid, because I can't help thinking that in order to get day-long sunsets (and sun rises?) you would otherwise be paying for them with very complicated tides, amongst other things.

 

[Warren_Paul]

I was about to ask WP if there were sparkly vampires on his world.

... shudder ...

Doesn't that mean certain parts of the planet will be in constant daylight ?

Depending how you orbit the suns you can also have constant darkness. Might give you a small habitable zone in the twilight you seek.

That would be correct, on both counts. Its still just a concept for now. We often get at least temporary situations like that on earth. i.e. Alaska

 

[Glitch]

Would the twilight area be quite wet? Hot winds from the sunny side meeting the cold winds from the dark side - may the force be with you.

The obvious name for the planet was Twilight. But a certain teenage vampire series ruined that for me, now didn't it?

You could call it terminator, no vampires in that movie!

http://en.wikipedia.org/wiki/Terminator_(solar)

 

[Warren_Paul]

I'm am getting ideas here. The permanent night/day might separate the infected communities from the survivors on the planet... maybe. (see critique).

the survivors went were water is found, (twilight). the infected want the water supplies they have so attack the havens.

potential.

 

[Glitch]

Would they not have set up there to begin with?

Edit,

You could put the cities on the edge of the twilight / sunny side. Extra heat makes it a little uncomfortable to be outside for too long, and explains why they didn't start there in the first place.

 

[Warren_Paul]

Would they not have set up there to begin with?

That is true... anyway, something to think about.

 

[David Evil Overlord]

You could call it terminator, no vampires in that movie!

Or Terminus Est, in homage to Gene Wolfe's Torturer series.

I'm am getting ideas here. The permanent night/day might separate the infected communities from the survivors on the planet... maybe. (see critique).

the survivors went were water is found, (twilight). the infected want the water supplies they have so attack the havens.

potential.

One thing I saw in Italy was a town built on relatively flat ground, with a castle built behind it and higher up the hill, to protect the town and the spring which was the town water supply. This meant the town had a high stone wall with a triangular footprint, with the castle at the highest point/one corner of the triangle.

Readers might wonder why the towns don't use stone or concrete to build zombie-proof walls. I know stone requires stone, and skill to work it, while concrete requires water they may not be able to spare.

Of course, if your water sources keep drying up, then your settlements have to keep moving to follow the water. So building a castle is a waste of time and resources.

 

[Bowler1]

You could have water being brought in from outer space, i.e. comets. This is requires some effort to do, so build a castle/fort to protect the valuable water resource brought in from space. Some sort of space going cast system where the people with access to space technology rule, just an idea as it would provide a castle and water.

For Ursa Major, good point on tides but for human habitation there is a habitable zone so we can’t be too near the sun or the athmosphere would blow away, the suns cosmic stuff would do this! (I know what I mean but can’t think of the name this morning) or become a hot house, too far out and it gets chilly. However for a planet to stay spinning on a steady access, it has to have a moon. No moon and it would be a crazy spinning top. If Earth had no moon there would be a good chance humans would never have developed as north and south poles would switch on a regular basis with all the climate problems to boot. So a good planet with life should have a moon, this moon could be very close to the surface causing large tides. Phew!

Well done Paul, this thread has taken off.