Astroengineering (Earth-2915)

Astroengineering is name given to the construction of megastructures in space by technologically advanced beings. It is a form of megascale engineering, but deals with structures that are "easily observable" from interstellar distances with 20th century astronomical instruments: e.g. a space elevator is an example of megascale engineering, but it is not an example of astroengineering. A notable example of astroengineering are the Halo rings, built by the technologically advanced forerunners.

Construction of these megastructures are restricted to either Tier Zero, Tier One or Tier Two civilizations. As a Tier Three civilization, humanity has no astroengineered structures.

Source

 * https://www.halopedia.org/Astroengineering