|This article is about a/an planet in Chikyuu Sentai Fiveman.|
Doctor Hoshikawa and his wife left Earth for Sidon in 1962, with the hopes of trying to colonize and ultimately terraform the dead world to make it habitable. Living within the base of Magma Base with two alien assistants and their robot, Arthur G6, the duo work on a lab to develop life while having five children themselves.
By 1970, after eight years of development and work, Doctor Hoshikawa finally completes his greatest success: a plant successfully grown and a flower successfully blooming on Sidon's harsh soil! However just as the celebrations were occurring, the Silver Imperial Army Zone invade the world, deciding to intervene to immediately crush any possibility of life on the planet and make sure the world remains dead and destroyed. The Zone forces kill the Hoshikawa's alien assistants and force them to retreat, with the mother and father choosing to make a final stand on the world and instructing Arthur to take the children back to Earth. Zone's forces overwhelm Doctor and Midori Hoshikawa, presumably killing them as Magma Base departs Sidon with the five Hoshikawa children under Arthur's protection as they head for Earth.