I am currently building a planet that weighs about 4 earth masses and is 2.3 earth radii long. It is an ammonia planet (as the title suggests), and has ammonia oceans with some dissolved water ice, methanol, hydrazine, chlorethane, and salts (sodium, chlorides, sulfates, potassium etc.). The average temperature is about 225ºK on the planet and the avg pressure at sea level is about 4 atm.

All of my organisms require one (or more) of these three compounds for their metabolism and need to breathe them in as a result: gaseous ammonia, ethylene, and/or methane. To transport these elements, I would like to understand what cofactor would replace iron in hemoglobin to carry each of these three compounds. They should also be stable when in contact with each other, work in cells with liquid ammonia as a solvent, and work in relatively cold temperatures.

Also, as I understand, these molecules need to be broken up into radicals and transported, and then they are recombined.

Bonus points if you say what color their blood would be in each case!

  • $\begingroup$ carbon maybe or maybe. Though it's more likely hydrogen this stuff is easy to transfer from chemical compounds. @Neil Iyer $\endgroup$ Apr 9 at 17:08
  • 1
    $\begingroup$ The planet "is 2.3 earth radii long" - "long" is not normally used to describe planets. Is it a weird shape (very difficult for a science-based answer at that mass) or are you describing the diameter (or something else)? It may not be directly relevant, but I assume you are describing the planet for the purpose of calculating surface gravity... $\endgroup$ Apr 11 at 4:37
  • $\begingroup$ Maybe that was a bit awkward but it means that the planet's radius is 2.3 times that of earth's. $\endgroup$
    – Neil Iyer
    Apr 11 at 13:21
  • $\begingroup$ @Neil Iyer that is a very big planet. Though i don't think that would change much about the blood. $\endgroup$ Apr 11 at 13:32
  • $\begingroup$ Yeah, it was supposed to be a terrestrial planet so large that it is almost a mini-neptune, and I also don't think that would change much about the blood. IIRC, temperature and the gas needed to take in matters more in these kinds of situations. $\endgroup$
    – Neil Iyer
    Apr 11 at 13:41


You must log in to answer this question.

Browse other questions tagged .