|Darkseid's Stargate Portal|
These portals allow people to travel interstellar distances, and between dimensions, quickly by creating an apparent tube between two points through which people can travel.
They are powered by the mysterious X-element, which serves as a matter threshold.
- Boom tubes first appeared in Forever People, Vol. 1 #1 (March, 1971).
- They were created by writer-artist Jack Kirby.
- Boom tubes are described by Jack Kirby as a "bridge to Earth."
- The "science" of boom tubes has never been explained.