Stargate

Stellar gates, sometimes called stargates, use massive amounts of solar power in order to warp spacetime in order to literally reduce the distance beteen two such gates. Currently, seven exist inside the Solar System, each reaching nearby, major star systems. These giant megastructures reside some distance outside Neptune's orbit, providing (relatively) rapid transportation to nearby stars.

The massive energy required for these hundred-thousand kilometer behemoths makes it nearly impossible to use them around a red dwarf star, as even with the aid of mobius patterns, these seven gates require well over half of the sun's energy, averaging a need for thirty yottawatts of power each.

The seven gates so lead to the following star systems:

• Alpha Centauri (4.36) - The first gate constructed, activated in 2214 by the Centaurus Mission. It is sometimes called the Centaurus Gate. Alpha Centauri is host to the first gate not linked to the Solar System, connection the system directly to Sirius.
  • Alpha Centauri has one further gate under construction to Epsilon Indi.
• Sirius (8.58) - The second gate constructed, primarily because, as a brighter star, Sirius can be linked to more distant systems than Sol can. Sirius has both fully active gates not linked to Sol - to Procyon and Alpha Centauri. The former since the Concord has no desire to be reliant upon humanity for its resources, and Alpha Centauri's worlds are already host to nascent civilizations.
  • Another gate is under construction to reach Epsilon Eridani.
• Epsilon Eridani (10.32)
  • This system has two gates under construction. One with plans to reach Omicron Eridani, and another to Sirius.
• Procyon (11.40) - Host to the Procyon Concord, this gate was actually completed and fully active before Epsilon Eridani's was. It currently has only one additional gate active, giving the system direct access to Sirius.
• 61 Cygni (11.40)
  • One other gate is under construction in 61 Cygni - to Altair.
• Epsilon Indi (11.82)
  • Epsilon Indi has two further gates under construction, to Alpha Centauri and Delta Parvonis. Once completed, these gates, along with the one to Sol, will drain Epsilon Indi of nearly all of its light.
• Tau Ceti (11.88)
  • Tau Ceti has a single additional gate under construction, to link it to Epsilon Eridani.

Structure

Each of these will remain the seven largest megastructures created by human hands for some time, at least in terms of raw dimensions.