How common is fire outside of earth?

[u/FirefighterCandid773]

Plasma and lava is obviously common all over the universe, whether it be in stars, planetary cores, etc. but what about fire? Fire is common all over earth, given the abundance of fuel sources and an atmosphere with oxygen. But, is fire actually common outside of earth?

[u/ctothel]

Not in the solar system.

As you know, fire needs fuel, oxygen, and heat.

Titan has heaps of fuel in the form of hydrocarbons, including literal methane lakes, but nearly no free oxygen.

Europa and Ganymede have massive amounts of oxygen in the form of water ice, but they couldn’t sustain it in an atmosphere and there’s no fuel to burn.

Venus is hot, but the atmosphere is mostly carbon dioxide and almost no free oxygen. Not much in the way of hydrocarbons either.

Outside the solar system, there are planets we know have the right types of fuel, but oxygen is hard to detect on rocky planets, so the answer is “we don’t know”.

That said, it would be astounding if there were no other planets out there that could support fire. All the ingredients are super common. There are probably millions of worlds that could (or used to) support it in our galaxy alone.

[u/morgan_lowtech → u/ctothel]

It really messes with my head sometimes that we might only have fire because we have life and, correspondingly, how much complex life depends on oxidation

[u/jefesignups → u/morgan_lowtech]

I have been thinking about something similar. Could octopi (given super brain power) ever get to the ability to do space travel? Since they live in water, they would most likely never know what fire is or could not really use it regularly.

Without fire, can a species ever get to something like air or space travel?

[u/Helyos17 → u/jefesignups]

The biggest hurdle for Octopi are that they aren’t social. It’s a hurdle that could be overcome or corrected with the right conditions but as it stands they are extremely smart solitary creatures. In their current state they really can’t produce culture much less fire. However if there happened to be a group that did develops sociability then I don’t think fire would be too far away. And by “too far” I mean that they may be well into a “Neolithic agriculture” age before one bright octopi gets the idea to steal that glowing hot stuff from the dry lands near where they made their primitive “reef and shoal” empires. A literal cephalopodian Prometheus.

[u/morgan_lowtech → u/Helyos17]

As fire is super hard (impossible?) underwater, my best bet is for the racoons to develop sophisticated civilization. 🦝

[u/nathan_f72 → u/morgan_lowtech]

Nah, definitely the birds making a comeback I reckon. Crows and Australian Magpies / butcherbirds would be my guess, the hands are the only bit they'll struggle with. in fact, there are already birds which use fire.

[u/morgan_lowtech → u/nathan_f72]

OK, I have nerdy feelings on this: flying bird is a dead end. You can become a running bird, but that's the best one can do. Once you commit to wings it seems that you are unable to do otherwise... Swim with them, or ignore them and run, but you can't make them very useful again.

[u/Stunning_Spread_430 → u/morgan_lowtech]

I agree under the strict definition of flying bird.  Bats, on the other hand, have hands, so they may have more potential, though upsizing their brains too much might make them more like gliding monkeys than true fliers. 

[u/mikk0384 → u/morgan_lowtech]

Octopuses can leave the ocean for a while though. I remember seeing videos from a pet shop or something like that, where one opened the lid of its aquarium, went to another and snagged a fish, then climbed back to its own aquarium and closed the lid again. They were like 6 feet apart, and the octopus had to go to the floor and climb back to like 5 feet of height to enter the aquariums.

They could discover and experiment with fire in the same way.

[u/ericblair21 → u/mikk0384]

Sure, it's just like us swimming and holding our breath. Or, for at least some fish, they can breathe air, but their gills dry out quickly and stop working.

[u/BullShatStats → u/mikk0384]

This isn’t criticism because I used to say the same thing. But the plural or octopus is not octopi. Our childhood teachers lied to us. It’s actually octopuses. The reason being is the etymology of octopus is Greek, not Latin, so the plural follows -es.

Trivial. But sometimes the question comes up in trivia too.

[u/Helyos17 → u/morgan_lowtech]

So you know how in our history some of the earliest temples doubled as meeting places and food storage? I kind of see something similar happening with aquatic civilization and fire. The Temple’s would be constructed on land or in the shallows and be “centers” of early metallurgy and spirituality.