Give this Wikipedian a Cookie.

One of my Top Ten Favorite Wikipedia Articles is "Hypothetical types of biochemistry". While I do think that the fact that our ecosystem is based on carbon, water, and oxygen gas is pretty strong evidence that life elsewhere in the universe will be similar, I do not think it wise to treat this as a guarantee.

I've heard the term "silicon-based life" brought up before, and I've seen aliens that require methane and/or ammonia in sci-fi before.

On that last note...


"Ammonia World" by Ittiz - Own work. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Ammonia_World.jpg#mediaviewer/File:Ammonia_World.jpg

This picture is half the reason why this is one of my favorite Wikipedia articles. LOOK AT IT. It looks like Earth, only palette-swapped. Now I'm not going to just say that when you write your sci-fi planets you should palette-swap and call it a day; if you watched NatGeo's Extraterrestrial, which I linked to in my previous post, recall that both Aurelia and Blue Moon were predominantly blue planets like our own. But this guy/gal gives a clear and concise rationale for why it looks the way it does if you scroll down to read the image description:

-Dissolved alkali metals producing rust-brown oceans
-Oxides of nitrogen producing a reddish-orange atmosphere.
-Colder climate means the plants are black to absorb more light (an idea that's had some scientific evidence for a number of years now).

This is exactly the kind of thing I've been talking about. A world where life thrives but profoundly different than our own, at least in appearance. This is a world I can believe could exist. According to the Wikipedia article, ammonia is liquid "between −78 °C (195 K) and −33 °C (240 K)". That's a pretty narrow range- but that's just at standard Earth atmospheric pressure. Increase the pressure to 60 atmospheres, and "ammonia melts at −77 °C (196 K) and boils at 98 °C (371 K)". That's a pretty wide range. Maybe then the plants wouldn't have to be black.

I'd love to don a spacesuit and visit a world like this, and see how its ecosystem has thrived in an ammonia-rich environment.

So Ittiz, whoever you are, if you're reading this, I salute you and your creativity mixed with attention to scientific detail.

(A planet like this needs a good name though. Unfortunately I can't think of one appropriate to ammonia oceans and black plants.)