They may or might be implemented.
This part or feature is not in the game, but could be added in a future update.
Astronauts are human beings that can go to space using a rocket. They usually sit in the capsule during most of their mission.
Astronauts are yet to be added in the game, but were also made by the players by clipping fuel tanks together to show what they might look like once released.

Picture of an astronaut in the game files.
Rumours[]
Astronauts will be able to do EVAs and they will run out of oxygen. Stef has previewed an infinite oxygen cheat.
According to the game's code, their oxygen supply will last for 7200 seconds (or 2 hours), and can be used as a backup RCS propellant if out of fuel. The code also suggests that they will be able to pick up and store planet rocks in their inventories.
Astronaut-related parts include an Crew Seat and a Lander Can. These objects were found in the game's files but are hidden. There are also a few achievements that people have found:
Collected a rock from the surface of the Moon
Performed a spacewalk in low Earth orbit
Performed a spacewalk on the surface of the Moon
Information[]
- The astronauts appear to be able to collect rock samples from planets and bring them back to Earth, however, it is unknown what these rock samples will do.