The Time Capsule is a tool that is used during the endgame of Subnautica. A Time Capsule can be jettisoned via the Neptune Escape Rocket's Cockpit, and can be edited to include a screenshot, various items, and a message for later players to find.
Upon being sent, Time Capsules are sent to this website on which people can upvote and downvote Time Capsules. Capsules with enough upvotes, after being screened, will be seeded into the game world for players to find.
Time Capsules can be found at random points on the seabed, and can be opened to find various items, a screenshot and a message From the player who made the time capsule. Discovered Time Capsules are imported to the PDA and can be read again.
Data Bank Entry
These sturdy containers are designed to store written and photographic evidence for later retrieval, in addition to a number of small items. Time capsules are often fabricated by marooned survivors seeking either to aid those who find themselves in the same predicament in the future, or to leave evidence of their plight which may be found long after their bodies have disintegrated.
Most emergency escape vehicles are equipped with a time capsule by default, usually found in the cockpit, and be jettisoned on take off. Alterra requests time capsules be stocked with tools and resources which will aid those who may discover them in the future.