Games like Periapsis: Gravity Slingshot
Games like Periapsis: Gravity Slingshot include Kerbal Space Program, Universe Sandbox, X4: Foundations, Stellaris, and Elite Dangerous. We matched them by the tags players give Periapsis: Gravity Slingshot on Steam (Space Sim, Simulation, Strategy, Space, and Physics): closest matches first, and among equally close ones the better-known games.
Kerbal Space Program
Shared: Simulation · Space · Space Sim
Universe Sandbox
Shared: Simulation · Space Sim · Space
X4: Foundations
Shared: Simulation · Space Sim · Space
Stellaris
Shared: Strategy · Space · Simulation
Elite Dangerous
Shared: Space Sim · Space · Simulation
Hardspace: Shipbreaker
Shared: Simulation · Space · Physics
Kerbal Space Program 2
Shared: Space · Exploration · Physics
Spaceflight Simulator
Shared: Space Sim · Simulation · Space
Dyson Sphere Program
Shared: Space · Simulation · Resource Management
Empyrion - Galactic Survival
Shared: Simulation · Space · Space Sim
SPORE™
Shared: Simulation · Space · Exploration
FTL: Faster Than Light
Shared: Strategy · Space · Sci-fi
No Man's Sky
Shared: Space · Exploration · Procedural Generation
Space Engineers
Shared: Space · Simulation · Physics
Space Haven
Shared: Strategy · Space · Simulation
Oxygen Not Included
Shared: Resource Management · Simulation · Strategy
Totally Accurate Battle Simulator
Shared: Simulation · Strategy · Physics
Solar Expanse - Space Exploration Manager
Shared: Simulation · Space · Physics
EVE Online
Shared: Space Sim · Exploration · Simulation
X Rebirth
Shared: Simulation · Space · Space Sim
Cities: Skylines
Shared: Simulation · Strategy · Resource Management
Cosmoteer: Starship Architect & Commander
Shared: Space · Space Sim · Strategy
Universe Sandbox
Shared: Simulation · Space · Physics
SpaceEngine
Shared: Space Sim · Space · Casual