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The algae planet is an unnamed, habitable world possessing a debris ring, and oceans and seas on its surface. It orbits an unstable sun, and is located in close proximity to an intense, blinding, and highly radioactive star cluster.
After the fleet of surviving Colonial ships discovers its food stores are contaminated and sends out scouts to search for a new food source, Sharon Agathon returns from her recon of the planet and confirms that edible, protein-rich algae grows there. The fleet makes the dangerous crossing of the star cluster, and sets up stations on the planet to harvest and process the algae (TRS: "The Passage").
Two weeks later, as harvesting is wrapping up, Galen Tyrol is inexplicably drawn to a mysterious structure, the Temple of Five, which was built by the Thirteenth Tribe approximately four thousand years before. The Sacred Scrolls describe this as the location of the Eye of Jupiter, an artifact that can potentially point the way to the Thirteenth Tribe's destination, Earth. Shortly afterwards, a Cylon fleet appears over the planet, also seeking the Eye, leading to the Battle of the Algae Planet (TRS: "The Eye of Jupiter").
As predicted by Felix Gaeta, the planet's unstable sun eventually goes nova. Before escaping the planet's surface, Tyrol realizes that the nova itself is the clue, leading the fleet to the location of a similar nova millennia earlier. Both fleets jump away just as the nova's shockwave consumes and obliterates the planet (TRS: "Rapture").