Oozora 【大空】4 The Japanese surnames etymology dictionary.
① "Sheng" is a favorable character. Hyougo-ken Tatsuno-shi Miyazu told that Asagi was engaged in agriculture. Estimated in the Edo period. It is distributed in Okinawa-ken Ishigaki-shi . Same name including "Sheng" on the same place.
② variant of 大森 . Iwate-ken Hanamaki-shi Iwate-ken Morioka-shi Uchimaru reports that the lord of Morioka lord of the clan government gave a letter of "Sheng" and changed from Omori surname in the Edo period.