Overview
The "science" of boom tubes has never been explained, (as is normal for the New Gods, though Orion, in the first issue of New gods, says that a tube "stems from the waves of the mind") but they allow people to travel interstellar distances, and between dimensions, quickly by creating an apparent tube between two points through which people can travel. When used, a low humming accompanies the formation of the "tube" - a tunnel of rippling circles of light - which increases as the tube is maintained and traversed, ultimately culminating in a loud "booming" noise when it closes. This "boom" has been known to knock bystanders off their feet and shatter glass, and gives the technology its name. The tubes need to be generated or opened by another device, commonly a Mother Box. Boom tubes are powered by the mysterious X-element, which serves as a matter threshold.
The initial Kirby comics depict boom tubes as a sort of quasi-technological equivalent of Bifröst, the Rainbow Bridge linking Asgard and Earth; indeed, boom tubes are described as a "bridge to Earth." Subsequent writers have allowed the tubes to be used for point-to-point transport between various locations on New Genesis, Apokolips, Earth, and other planets, thereby making them near-ubiquitous for the travel of the New Gods. Boom tubes replaced other mostly undefined concepts like the Electron Road, the Matter Threshold and the Star Gate, all of which have been used by the New Gods for travel from either New Genesis or Apokolips.
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