Games like Astrominer
Games like Astrominer include Terraria, Starbound, No Man's Sky, EVE Online, and Elite Dangerous. We matched them by the tags players give Astrominer on Steam (Adventure, Arcade, Exploration, Platformer, and Sandbox): closest matches first, and among equally close ones the better-known games.
Terraria
Shared: Sandbox · Adventure · Exploration
Starbound
Shared: Adventure · Sandbox · Space
No Man's Sky
Shared: Exploration · Space · Open World
EVE Online
Shared: Exploration · Adventure · Space Sim
Elite Dangerous
Shared: Exploration · Space · Space Sim
Rain World
Shared: Exploration · Platformer · Adventure
ASTRONEER
Shared: Exploration · Space · Open World
SPORE™
Shared: Sandbox · Exploration · Open World
Kerbal Space Program
Shared: Space · Sandbox · Space Sim
Hollow Knight
Shared: Platformer · Exploration · Adventure
Slime Rancher
Shared: Adventure · Exploration · Open World
Kerbal Space Program 2
Shared: Exploration · Sandbox · Space
Outer Wilds
Shared: Exploration · Adventure · Space
Core Keeper
Shared: Exploration · Open World · Sandbox
Avorion
Shared: Exploration · Sandbox · Space
The Forest
Shared: Adventure · Open World · Exploration
Spaceflight Simulator
Shared: Sandbox · Exploration · Space
The Long Dark
Shared: Exploration · Adventure · Open World
Empyrion - Galactic Survival
Shared: Space · Exploration · Open World
Keplerth
Shared: Adventure · Exploration · Sandbox
Fallout 4
Shared: Exploration · Adventure · Open World
FEZ
Shared: Platformer · Exploration · Adventure
Planet Centauri
Shared: Exploration · Sandbox · Open World
Don't Starve
Shared: Adventure · Sandbox · Exploration