Welcome to Day 2 (Part 1) of Ocean Worlds Week!

For today's first thread, I'm going to quickly discuss how life could possibly exist on some of these ocean worlds, specifically using Europa and Titan as examples, which is super exciting! Let's get started! #scicomm (1/11)

So you might be wondering how exactly life could live on another planetary body that isn't Earth, and what it may look like. Well, it's a lot more plausible than you may think! Let's take our first example, Europa. This Galilean moon has an icy shell that probably hides... (2/11)

...beneath it a liquid water ocean. An energy source that may be available to theoretical organisms living there may be produced through a combination of Jupiter's radiation and the plumes on Europa. These plumes expel water from the subsurface ocean and radiation... (3/11)

...breaks down the water into hydrogen and oxygen. The hydrogen floats away, leaving the oxygen behind, helping create the thin oxygen-rich atmosphere on Europa. If this oxygen was somehow able to reach the subsurface ocean, it could be utilized as an energy source! (4/11)

Another possible energy source may come from within the ocean itself. It's pretty salty, containing the same kind of salt we need to harbor life here on Earth, so we're off to a good start. Interactions between the salty ocean and the rocks on the seafloor bed could... (5/11)

...be a source of energy for organisms to live. Also, the existence of hydrothermal vents could be helpful as well, as they are able to bring in heat and transport material from Europa's interior to the seafloor bed, possibly providing nutrients.

Since life on Europa... (6/11)

...would depend on chemical reactions, the type of life we would most likely find is microbial, so no space whales yet!

There is a mission that has been developing called the Europa Clipper that is going to do extensive research on all this (I'll do a thread on it soon!) (7/11)

Now onto Titan, which is a completely different beast. Titan is really really interesting because not only does it have a subsurface ocean, it has rivers and seas on its surface of liquid hydrocarbons such as methane or ethane. Some use this as an argument against the... (8/11)

...hypothesis of life existing there. There is also the fact that any water on its surface would be frozen solid due to its cold surface temperature. Though this may possibly feed into the idea that we don’t know whether non-water-based life could exist, which is wild! (9/11)

Titan also has a full-fledged atmosphere that is thick and contains organic compounds meaning organisms could possibly utilize these compounds as an energy source.

There's a robotic mission planning on going to Titan called Dragonfly that'll look for life! (Thread later) (10/11)

So that's how life could possibly exist on ocean worlds! Later today I'll post a short FAQ thread answering some questions some people have asked before, so if you have any, please make sure to reply below! (11/11)

Question: Do you think we'll find life on one of these moons?