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The algae planet is an unnamed, habitable world possessing a debris ring, and oceans and seas on its surface. It is almost surrounded by an intense, blinding and highly-radioactive star cluster.
In "The Passage", the Fleet discovers its food stores are contaminated and sends out scouts to search star systems to find a new food source before the population starves. Sharon Agathon returns from her recon of the planet and confirms that edible, protein-rich algae grows there, but that the star cluster cannot be navigated around in time before food runs out; the Fleet must navigate through it. Using the radiation-hardened Raptors as guide ships, all but a few of the civilian ships manage to cross the star cluster and reach the planet. Once there, stations are set up on the planet to harvest and process the algae to resupply the Fleet.
After 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 4,000 years before. The Sacred Scrolls describe this as the location of the Eye of Jupiter, an artifact that points the way to the Thirteenth Tribe's destination, Earth. Shortly afterwards, a Cylon fleet appears over the planet, also seeking the Eye, resulting in the Battle of the Algae Planet (The Eye of Jupiter).
As predicted by Lieutenant Gaeta, the planet's unstable sun eventually goes nova. The Colonials evacuate the planet and both fleets jump away just as the nova's shockwave reaches and consumes the planet. The nova itself turns out to be the Eye of Jupiter, and a similar nova, which occurred around the time of the first exodus, gives the Colonials their next clue to the way to Earth (Rapture).