The Aldhan system (also spelled Ahldan) is a star system orbiting a single K class star in the Venturi sector. It includes 8 planets and an asteroid belt.

• Ahldan
  • Alhdan I
  • Aldhan II
  • Aldhan III ("Doorok")
  • Aldhan IV
  • Aldhan V
    • Asteroid belt
  • Aldhan VI
  • Aldhan VII
  • Aldhan VIII

Aldhan III, also known as "Doorok", is a Vulcan science colony that studies the native Silicon and Carbon based lifeforms that cohabit the planet. (TOS video game: Star Trek: Starfleet Academy - Strategic Command)