Purple planet

I saw this type of planet in a Celestia add-on for Alpha Centauri. What atmospheric chemistry would be possible that would result in a purple planet (purple sky, oceans, etc.)? Could this be possible, or not?

Remember that most of the Celestia add-ons aren't scientifically valid at all. I would guess though, that some combination of blue oceans + reddish atmosphere might do the trick. But I really don't know.

T dwarfs would supposedly appear purple, but this is the case of an isolated object glowing from its own internal heat. What a T dwarf being illuminated by a nearby star would look like, I don't know.

So, maybe an icy planet around a T dwarf (MOA-2007-BLG-192Lb perhaps?) would look sort-of purplish?

Sirius_Alpha wrote:Remember that most of the Celestia add-ons aren't scientifically valid at all. I would guess though, that some combination of blue oceans + reddish atmosphere might do the trick. But I really don't know.

You're probable right, I guess I was fooled. Either way, it was worth the ask

Sorry to bring this up again, but I think I found something. I ran into something that Ammonia planets may have a purple atmosphere and (in turn) purple oceans. Could this be the possible chemical? If not, what color would an Ammonia planet be?



Also, here is the Celestia look at this "planet" (just so you get an idea of what I was talking about).

Blue ocean and red atmosphere is not possible. Since the water is a reflective color of the atmosphere. Unless there is something else I'm missing.

Purple planets could have an atmosphere similar to rare purple eye human. People with purple eyes are albinos with high collagen structures that causes Rayleigh effect. Blue + Red = Purple. So, a planet's atmosphere that has a lot of dust or structures that causes blue Rayleigh to reflect back out along with the red surface could produce a purple planet or of that tint.
http://en.wikipedia.org/wiki/Image:Human_eye_color.PNG

marasama wrote:Blue ocean and red atmosphere is not possible. Since the water is a reflective color of the atmosphere. Unless there is something else I'm missing.

I think that some of the blue colour of the water comes from the Rayleigh effect.

... you haven't answered any of my questions.

NuclearVacuum wrote:... you haven't answered any of my questions.

1) One possibility could be the red surface and an atmosphere of particles that give blue light. Hence, making a purple color.
2) The atmosphere is filled with floating bacterium or life that is colored purple.

As for chemicals, I cannot think of any. A few minutes search on google for gas, atmosphere, and water yield zero finds.

marasama wrote:

NuclearVacuum wrote:... you haven't answered any of my questions.

1) One possibility could be the red surface and an atmosphere of particles that give blue light. Hence, making a purple color.
2) The atmosphere is filled with floating bacterium or life that is colored purple.

As for chemicals, I cannot think of any. A few minutes search on google for gas, atmosphere, and water yield zero finds.

I also asked what color Ammonia planets would be.

I'm not so sure there is a simple answer to your question. As far as I know, the colours of plants are related to the wavelength they absorb. Earth-like plant life in a red dwarf system are speculated to be darkly coloured to absorb more IR light--the primary output of a red dwarf star.

Here are some links that might help you.
http://www.sciam.com/article.cfm?id=the-color-of-plants-on-other-worlds
http://www.space.com/scienceastronomy/070411_nongreen_plants.html
Sadly, the picture is gone. I did DL'ed the picture, though.

But again, the colors depend on the senario of evolution. On Earth, the green plants reject the best color that our Sun give. This is probably due to evolution where it had to compete with Purple Bacterium. Since the purple bacterium are absorbing most of the lights in green, the plants had to get the remainder of the lights, blue & red. Hence, that is why are plants are green (if of course, the theory holds true).
http://www.livescience.com/environment/070410_purple_earth.html

Other planets, it will depend on their evolution. We even got fungus on earth that photosynthesis gamma-ray light. So, infinate possibility.
http://en.wikipedia.org/wiki/Radiotrophic_fungus

Here's a list of chemicals I compiled over the years.
http://marasama.googlepages.com/PlantColor.html

Another rule to remember, the color of the plant will likely be the color it rejects. Remember, a red cup is every color but red (roughly), 'cause red is the color that is bouncing off the cup and entering our eyes.

So the answer for the plant color is, "any color you want".
Hope this helps.

Oh yeah, the plants can also be a variety of colors on the same planet, too.