Feasibility of life on a Flesh Planet?

Question

The context is a spacefaring civilisation decides to dump its refuse and biomatter into space. Due to a technical error, the biomatter doesn't fall into the nearby star but instead finds a stable orbit around it. Or it finds itself in a lagrange point, maybe one which protects it from the star's solar radiation. With enough organic material, it would become the size of an earth-like planet.

If the biomatter being launched into space is thick enough, then I envisioned it acting like a spaceship for bacteria, insects and small mammals. They would be protected from the elements by the flesh and biomatter and would also have instant access to stores of food. Those that survived the trip would merge with the rest of the flesh planet.

With enough mass, I saw the decomposition of the flesh by the bacteria would allow for an atmosphere to form. Life would then be able to burrow itself to the surface and live on a flesh planet. With constant dumping of flesh and biomatter, I was hoping that the planet would maintain the same physical characteristics of flesh.

Would this or any similar scenario be possible?

Answer 1

An answer to a sort of similar question has been provided in XKCD What if 4

What would happen if you were to gather a mole (unit of measurement) of moles (the small furry critter) in one place?

Mammals are largely water. A kilogram of water takes up a liter of volume, so if the moles weigh $4.52×10^{22}$ kilograms, they take up about $4.52×10^{22}$ liters of volume. You might notice that we’re ignoring the pockets of space between the moles. In a moment, you’ll see why.

let’s gather the moles in interplanetary space. Gravitational attraction would pull them into a sphere. Meat doesn’t compress very well, so it would only undergo a little bit of gravitational contraction, and we’d end up with a mole planet a bit larger than the moon.

The planet would start off uniformly lukewarm—probably a bit over room temperature—and the gravitational contraction would heat the deep interior by a handful of degrees.

The mole planet is now a giant sphere of meat. It has a lot of latent energy (there are enough calories in the mole planet to support the Earth’s current population for 30 billion years). Normally, when organic matter decomposes, it releases much of that energy as heat. But throughout the majority of the planet’s interior, the pressure is over a hundred megapascals, which is enough to kill all bacteria and sterilize the mole remains—leaving no microorganisms to break down the mole tissues.

Closer to the surface, where the pressure is lower, there’s another obstacle to decomposition—the interior of a mole planet is low in oxygen. Without oxygen, the usual decomposition doesn’t happen, and the only bacteria that can break down the moles are those which don’t require oxygen. While inefficient, this anaerobic decomposition can unlock quite a bit of heat. If continued unchecked, it would heat the planet to a boil.

But the decomposition is self-limiting. Few bacteria can survive at temperatures above about 60 °C, so as the temperature goes up, the bacteria die off, and the decomposition slows. Throughout the planet, the mole bodies gradually break down into kerogen, a mush of organic matter which would—if the planet were hotter—eventually form oil.

The outer surface of the planet radiates heat into space and freezes. Because the moles form a literal fur coat, when frozen it insulates the interior of the planet and slows the loss of heat to space. However, the flow of heat in the liquid interior is dominated by convection. Plumes of hot meat and bubbles of trapped gases like methane—along with the air from the lungs of the deceased moles—periodically rise through the mole crust and erupt volcanically from the surface, a geyser of death blasting mole bodies free of the planet.

Answer 2

If couched in Lovecraftian prose, then yes.

I propose you live up to your moniker, Felix. Set aside your astrophysics and biology knowledge; someplace you can find it later. Then get reading - dig in to that Lovecraft and break it up with Rime of the Ancient Mariner and a little Poe. Then take yourself back a century and describe just as you propose, but lean into it. Fantastic horrific flesh worlds are fine Lovecraftian horror fiction.

Answer 3

When matter the mass of Earth clumps due to gravity, about 2*10^32 J of gravitational potential energy is turned into heat. (That is the gravitational binding energy of Earth)

The Earth has a volume of 10^12 km^3. Flesh is basically water, so this flesh planet has a mass of 10^24 kg.

It takes 4000 J to heat 1 kg of water by 1 K, so 4 * 10^27 J increases the meat-planets temperature by 1 K.

So this places the planet at 50,000 K. Which is, of course, ridiculous; what really is going on is that this measures how much heat the meat planet has to bleed off in order to form.

The resulting structure isn't going to be very biology based. Biochemistry will be sterilized.

Now this flesh sphere will not have the same density as Earth; it will be about 5 times less. That lowers binding energy for the same radius by a factor of 25, so down to 2000 K. So you'll end up will a bunch less heat to bleed off. But it will still far surpass sterilization levels.

The material will differentiate, and you'll get a core of solid carbonish stuff wrapped in a boiling ocean, above which you'll have a mostly steam atmosphere with impurities.

The body has to be pretty small not to boil. A way of looking at it is that any "planet" sized body got hot enough to melt the rocks that formed it into a sphere, and that requires less heat than sterilizing flesh.

Answer 4

Randel Monroe's Mole of Moles essay does not apply here

The Mole of Moles essay assumes that all of the biomass is added at once in the absence of outside forces, meaning the stuff in the middle will not be able to decompose, but this planet is formed through accretion over time which yields a very different outcome.

Depending on how close you are too the star, this biomatter will either be frozen or cooked by the star's radiation before accreting. Since your civilization was aiming for the star, I will assume that you looking at very close orbit like mercury allowing most of the biomass to be very thoroughly cooked before it accretes. Cooking the biomass means that most of the gaseous elements (Like Hydrogen, Oxygen, and Nitrogen) will be liberated from the biomass and pushed off into deep space by solar winds while the less easily vaporized elements like carbon, calcium, and phosphorous will remain behind. This will result in an orbiting cloud of ash BEFORE it can come together to form a planet.

Over time this ashy cloud will form into asteroids that will collide forming bigger and bigger asteroids yielding increasingly energetic impacts until you get something big enough to sweep the orbit forming a planet. Since the new planet's core is non-ferrous, it will not form a magnetic field to protect it from solar radiation; so, any last remnants of water vapor or other gasses released will be quickly blown away into space. It also lacks enough radioactive isotopes to maintain a molten core; so, the core will quickly cool down and harden making it volcanically inert.

This will basically leave you with a planet made up of about 85% carbon, 7% calcium 5% phosphorous, 1.5% sulfur, and 1.5% other stuff.

In the birthing stage of your planet, rapid powerful accretion impacts will cause crystallization and shattering to occur meaning that your planet will likely have a regolith surface similar to the moon, but instead of being made mostly of oxides and silicates, it will be made mostly of things like graphite, diamonds, calcium carbide, and calcium phosphate.

So, to answer your question about the viability of life, you are missing many helpful ingredients like an atmosphere, magnetosphere, water, etc. However, the planet will contain a high volume of industrially useful compounds not widely found on normal planets; so, you may find intelligent life showing up to mine the place...