I'm trying to create a fictional world where the primary species breathes in gaseous nitrogen to survive (and hence relies on ammonia). I'm currently working with a planet that would be about the same distance from its star as Earth is from the Sun (as it is most ideal distance for life to flourish). I realize this may be a bit of a stretch, as already Earth has an atmosphere primarily made up of nitrogen, but I'm looking to make the world more structured in gaseous nitrogen than Earth is (of course, still mixing other gaseous elements in the atmosphere such as oxygen and argon).

Would this be possible (even in fiction) or are these specifications going to ensure life is impossible on the planet? Would the weather have to be a certain temperature and type? Could this species survive on earth?

*Edited to make the question simpler, correct wording, and make more precise.

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    $\begingroup$ Our very own planet has an atmosphere which is 78% nitrogen. So your planet could be exactly like Earth. $\endgroup$
    – Tim
    Oct 18, 2017 at 6:04
  • $\begingroup$ Earth atmosphere is made primarily of nitrogen, and we have bacteria that use nitrogen from air. Not exactly "breathe" it, but still. I don't think you gave any requirements that would make your world not Earth. $\endgroup$
    – Mołot
    Oct 18, 2017 at 6:05
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    $\begingroup$ Nitrogen is very stable with that triple bond it has, so it may be difficult to breathe it in order to metabolize. $\endgroup$
    – timuzhti
    Oct 18, 2017 at 6:06
  • $\begingroup$ How hot is your planet? Nitrogen can be used, Oxygen is just better. Nitrogen wouldn't be optimal under otherwise earth-like conditions. One of the reasons why earth has so much nitrogen in the atmosphere is because the molecule is so stable. also consider: oxygen is a pretty common element and water (contains oxygen) is the best solvent we know for life. so not having it in the atmosphere could be interpreted as not having life on the planet - I'd advice to have no liquid water on your planet : courses.lumenlearning.com/cheminter/chapter/… $\endgroup$
    – Raditz_35
    Oct 18, 2017 at 6:13
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    $\begingroup$ It is customary here to wait at least 24h before accepting answers. This site is used by people all over the world. At any given hour most of them are at work or it's night where they live. By accepting so soon you tell them their contribution is no longer needed, and you don't even know what pieces of knowledge and creativity you are losing. $\endgroup$
    – Mołot
    Oct 18, 2017 at 7:45

2 Answers 2


If you want to have a life based on Nitrogen, you need to have environmental conditions which enable the presence of liquid and gaseous ammonia (NH3), more or less like we have on Earth with water. This because you need a solvent where all the reactions needed for life can take place. Since you want to have nitrogen-based life, ammonia (NH3) seems the most logic choice.

A biosphere based on ammonia would likely exist at temperatures or air pressures that are extremely unusual in relation to life on Earth. Life on Earth usually exists within the melting point and boiling point of water at normal pressure, between 0 °C (273 K) and 100 °C (373 K); at normal pressure ammonia's melting and boiling points are between −78 °C (195 K) and −33 °C (240 K). Chemical reactions generally proceed more slowly at a lower temperature. Therefore, ammonia-based life, if it exists, might metabolize more slowly and evolve more slowly than life on Earth

I assume that with "green life" you mean organisms capable of photosynthesis. On Earth this happens by intake of CO2 and H2O and release of O2 and CxHyOz. Since you are replacing CO2 with NO2, your world would be more on the reddish aspect. So I doubt a strictly "green" life could be possible.

This is how an ammonia based world could look like (same source as above).

enter image description here

  • $\begingroup$ Wow, the planet looks so cool! $\endgroup$ Oct 18, 2017 at 16:54

Edit after update of the question : maybe like Precambrian Earth

It will be purely gaseous planet, Obnoxious gas clouds at some high pressure regions, life forms are impossible as there is no hydro carbon or basic CHON compounds or minerals

It's more of cloud than planet, I'm not sure if gravitational force can hold the planet

Even if is possible, it would be a dark frozen planet, Temperature would be sub zero, color of cloud/planet would be grayscale

  • $\begingroup$ While you are right, I think that the OP meant atmosphere rather than the entire planet. $\endgroup$
    – Olga
    Oct 18, 2017 at 5:58
  • $\begingroup$ The OP never specified the distance from the star, size and mass of the planet. How can you venture forth without those info? $\endgroup$
    – L.Dutch
    Oct 18, 2017 at 5:59
  • $\begingroup$ It's impossible to have atmosphere 100% of only N& O gas unless the entire planet is made up of it $\endgroup$
    – Wynn
    Oct 18, 2017 at 6:02
  • $\begingroup$ Recalling what I learned in science, the distance Earth is from the Sun is the "ideal" location for life to form on a planet (due to radiation from the sun, etc.), so the distance between my imaginary "planet" and its star would be similar to that of Earth and the Sun. Venturing to size and mass, I'll admit I have not taken that into account yet (I'm only just working out the intricate details to the fictional planet, which is why I'm here asking questions :D). $\endgroup$
    – Bookkitty
    Oct 18, 2017 at 6:03
  • $\begingroup$ I have pre assumed some assumptions, please make sure of your question $\endgroup$
    – Wynn
    Oct 18, 2017 at 6:14

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