Plants on planets around red dwarves

[Space Nerd]

I'm making some space themed art featuring proxima b and trappist-1 e, and I drew purple and red plants on them for aesthetics (black doesn't look that good), is that scientifically plausible?

[Nightside]

15 minutes ago, Space Nerd said:

I'm making some space themed art featuring proxima b and trappist-1 e, and I drew purple and red plants on them for aesthetics (black doesn't look that good), is that scientifically plausible?

There are plenty of very dark purple/red plants here on Earth. The visible color of the plant is the wavelengths of light it does not absorb. For a sun that only puts out light in a limited (red) part of the spectrum I would guess that they would be trying to absorb as much red as possible, so maybe the plants would tend toward blue and violet.

[Spacescifi]

4 hours ago, Space Nerd said:

I'm making some space themed art featuring proxima b and trappist-1 e, and I drew purple and red plants on them for aesthetics (black doesn't look that good), is that scientifically plausible?

 

 

True scientific discoveries often don't match assumptions based on outdated theory still on paper and in use.

But I digress. Follow the evidence where it leads. Accept nothing else.

If and when humans or our machines ever reach Proxima, the plants we plant (which will require locally found or imported oxygen) would likely be that color.

But given the danger of the flares, I am guessing one would need a shielded habitat, or else it will be wrecked when the flare hits.

Other solar systems do not easily support life like our own.

 

 

https://www.google.com/amp/s/www.space.com/amp/42196-red-dwarf-star-hazflare-bad-news-life.html

 

Edited May 3, 2020 by Spacescifi

[kerbiloid]

As the soft red photons are soft, so photosynthetic reactions are not activated by such photons more often, I guess they would absorb as much as they can those strong, yellow-green-blue photons.
So, I would guess they are tending to be dark-red from this pov.

On another hand, there is a lot of red there, so quantity beats quality, so they should absorb red, so look dark-teal.

So, I would not be very surprised if they have two kinds of that, maybe in layers.
The upper layer of plants is dark-red, because it absorbs yellow-green-blue photons and grow faster.
And beneath it there are numerous dark-teal wide rounded leaves of low dark-teal plants, absorbing the scattered red.

[Wjolcz]

Or maybe photosynthesis is too much of a hassle around red dwarfs. As a plant you spend your already limited resources to grow leaves that don't make much energy. And, if there's any kind of ecosystem (and if we assume there are plants then there are also animals) those leaves are going to be eaten quick. So, harvest energy some other way?

Edited May 3, 2020 by Wjolcz

[munlander1]

10 hours ago, Wjolcz said:

So, harvest energy some other way?

So something like chemosynthesis?

[Scotius]

Or this:

https://en.wikipedia.org/wiki/Radiotrophic_fungus

Why not make use of those pesky radiation flares blasting the surface every now and then?

[Space Nerd]

So, I'll say both purple, indigo , and red plants are plausible, is that correct?

[Guest]

Chemosynthesis is extremely limited by the availability of reagents, so photosynthesis is still likely the best bet around a red dwarf. Radiotrophics require a consistent (or at least reasonably periodic), large flux of low energy ionizing radiation. Gammas will typically go straight through a typical microorganism, UVs are better at being absorbed. Using alphas and betas is also possible, if they reach the surface. Of course, if a radiotrophic ecosystem survives long enough, large organisms may evolve to absorb highly penetrating radiation better. Photosynthesis is a good bet because light is easy to absorb and there's so much of it even around a red dwarf.

[Wjolcz]

1 hour ago, Space Nerd said:

So, I'll say both purple, indigo , and red plants are plausible, is that correct?

Going with black is the safest bet. Reflecting red is probably a bad idea since these plants would want to absord as much light as possible. If red is bounced off then that leaves IR and maybe UV. IR is less energetic than red.

Although, maybe by absorbing infrared these plants could get hot and 'boil' some special absorbent to get energy. I don't know what kind of absorbent would be needed though.

One thing I know however is that siamese cats have a special protein which is supposed to produce melanin but because their bodies get too hot (for that special protein) it unfolds and never makes any melanin. That's why they are mostly white. So perhaps plants could figure out something similar but with sugars?

Edited May 4, 2020 by Wjolcz

[Space Nerd]

My logic is the red plants live closer to the substellar point, so they need to reflect infrared and red light in order to not overheat.

[sevenperforce]

2 hours ago, Space Nerd said:

My logic is the red plants live closer to the substellar point, so they need to reflect infrared and red light in order to not overheat.

Plausible enough.

[K^2]

Something that operates on longer wavelengths might use a pigment with metastable excited state using a double-photon absorption to get sufficient energy. There are known organic dies with fluorescence in near IR range that would be perfect starting point for such an energy-capturing molecule. Furthermore, if it has double captures in 800-1200nm range, it would imply another absorption band with single capture in the 500-600nm range, leading to a magenta appearance of the plant in the visible light. That's just one out of many, many possibilities. Most Earth plants have multiple pigments, which are effective at absorbing reds and blues. But far from all. We have pretty good variety even down here. It's hard to rule out any possibility for a plant living on another planet somewhere.

Edited May 4, 2020 by K^2