A Space Monster is Born on Earth (地球生まれの宇宙怪獣 Chikyū Umare no Uchū Kaijū) is the twenty-seventh episode of Ultraman Cosmos.
Space Monster Zaranga suddenly arrives. But apparently, it came to give birth. Because its temperature rises when it's close to giving birth, Zaranga has an instinct to give birth in Earth's ocean. But, this time, Zaranga appeared in the mountains...
A space monster fell on the mountains, apparently its body remain submerged after the impact from the fall. Cosmos successfully dislodged it when Team EYES fail and after learning that she was pregnant, he pacify her into sleep with Full Moon Rect.
"The flaming beast from heaven. From the sea rose to heaven large and small."
- ―Records of Edo period.
Mr. Ikeyama from SRC arrived and reveal the monster's name to be Zaranga, who came to Earth once in a while to give birth to a child by diving itself into the ocean. Its earliest record of arrival was from the Edo period of Japan and Zaranga's reasoning is also to cool off its drastically increasing body temperature as a result from the pregnancy. Zaranga was supposed to dive into the sea, but her trajectory because of the firework festival (and as Ayano summed it up, pregnant women has aversion for burnt stench).
Fearing that an awakened Zaranga will walk into the residential area, EYES planned to divert her path so she could made it to the sea without any casualties. Musashi and Fubuki use the Shepherd patrol car as baits but the plan was almost sidetracked due to an unexpected group of tourists. Cosmos appears and cool off the heating Zaranga before he dragged her into the ocean. She gave birth to her baby without much trouble and the family pair departed for space.
- Musashi Haruno (春野ムサシ Haruno Musashi): Taiyo Sugiura (杉浦 太陽 Sugiura Taiyō)
- Captain Harumitsu Hiura (ヒウラ ハルミツ 隊長 Hiura Harumitsu Taichō): Daisuke Shima (嶋 大輔 Shima Daisuke)
- Shinobu Mizuki (ミズキ シノブ Shinobu Mizuki): Kaori Sakagami (坂上 香織 Sakagami Kaori)
- Keisuke Fubukiフブキ ケイスケ (Fubuki Keisuke ): Hidekazu Ichinose (市瀬 秀和 Ichinose Hidekazu)
- Koji Doigaki (ドイガキ コウジ Doigaki Koji): Koichi Sudo (須藤公一 Sudō Kōichi)
- Ayano Morimoto (モリモト アヤノ Morimoto Ayano): Mayuka Suzuki (鈴木繭菓 Suzuki Mayuka)
- Ultraman Cosmos (ウルトラマンコスモス Urutoraman Kosumosu (Voice) : Hiroyuki Sato (佐藤浩之 Satō Hiroyuki)
- Ultraman Cosmos
- Luna Mode
Ultraman Cosmos Volume 6 features episodes 25-28.