Nibiru

Nibiru was a pseudo-intangible Dyson Sphere that build by Anunnaki as their Military base in our Solar system

History and Specs
following the War in Heaven(aka the war that (nearly) killed the Dinosaurs in 65 million BC, and Anu's subsequent ascension into Godlike Hyperdimensional galaxy brain), the Anunnaki people are undergoes Cosmic diaspora across the Multiverse, Enlil's old Vessel(that buried in it's watery grave in what later known as Bermuda Triangle just after crushed to death(in it's mecha) by an asteroid that wipe out dinosaurs) laid foundation of teleport beacon(that's looks like Pyramid on Bermuda Triangle's seabed) by the transmutation of it's old vessel that lead to the interior of Nibiru

the Nibiru itself was built on a star named Zaos where the Shell of Nibiru can make itself(and anything it envelopes inside) are both Intangible and Invisible due to the use of hyperdimensional physics, and the use of non-euclidean drive prevents the shell of this Dyson sphere from having any of it's parts pulled apart by Zaos' gravitational pull

the outer side of Nibiru was sparse features as it's Intangible and Invisible, but the inner side of Nibiru has lot of features: from Anunnaki offices, Factories, Laboratories,  and so on to the zoo that houses Extinct animals such as Dinosaurs(which explains 21st-century sightings of Extinct dinosaurs and the like due to the zoo's possible ties to Earth's ley-line nexus), sometimes the Animals that live here in it's Zoo are mutated and/or evolved into strange creatures due to Mutation from exposure to Empyrean(that allows their Physics-defying Biology to function), making them a basis for Magical Creatures in Real Life.

it's earthly access points are lies in Bermuda Triangle where everything that disappeared in Bermuda Triangle are goes into Nibiru, where everyone that disappeared here are used as hostage for Anunnaki for Power Plants as well science experiments and food source

the glimpse of Nibiru's inner side was once driven Jacques Cousteau to suicide

it's intangibility as well Vacuum of Space(that make Space silent) make it's further mysterious

and the total thickness of it's hull are about little thicker than Earth's crust