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").
After the battle, John Cavil questions Ellen Tigh about the events on the planet. Ellen confirms that the Final Five visited the planet on the way to the Twelve Colonies but they had nothing to do with the vision D'Anna Biers had of them while in the Temple of Five (TRS: "Rapture").
- Algae are simple aquatic organisms. Many are actually processed on the real-world Earth for use, among other things, as nutritional additives or foods.
- The algae planet parallels New Caprica as an intermediate home on the journey to Earth and appears to be a much more hospitable environment for human life. Its suitability as a permanent home, though, is rendered moot by the status of its sun, coupled with the fact that, like Kobol, it offers no protection from the Cylons.
- While there is no explanation outright given for Tyrol's ability to sense the Temple of Five while on the planet, its likely he was subconsciously guided there by his buried memories as he and the Final Five had visited the planet on their way to the Colonies.