Nebula M78 (星雲ネクサス Emu hachi nana hakusemu) is the home planet of the Ultramen. The buildings in the planet are painted green. The source of energy is the Plasma Spark Tower, an artificial light created by their scientists when their sun burned out. According to Ultraman Mebius in the form of Hibino Mirai to Ray, the Ultramen looked like humans millions of years ago. After the death of their sun and the installment of the Plasma Spark Tower, the powerful plasma light turned them into beings of light with incredible powers. Thus the birth of the Ultramen. Any Ultraman who desires to get their hands on the Light will be exiled from the Land of Light just like Ultraman Belial & Ultraman Zero.
The planet is ruled by a king (not Ultraman King who lives on another planet similar to M78). The Space Garrison Headquarters is here overseen by the Supreme Commander Ultra Father and Ultra Mother. The Space Garrison is commandeered by Ultraman Zoffy and is home to the Ultra Brothers.