"Hydrocarbon lakes" refers to bodies of liquid made up of compounds called hydrocarbons. These hydrocarbons are molecules made of hydrogen and carbon atoms. It is similar to how regular lakes are made up of water molecules, but instead,
hydrocarbon lakes consist of different types of molecules such as methane or ethane. They can be found in places like the moon Titan, where conditions are such that hydrocarbons can exist as liquids.
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