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Topography and ecology
Rahnelo was noted to look pristine from orbit. The planet has a thin equatorial band of deep greens and golden browns from native flora. From the equator, the planet's surface becomes colder and is completely covered in snow and ice, with polar caps that are icy blue in color. Rahnelo's star creates a sparkling effect on the planet when its light reflects off of Rahnelo's ice-covered surface. The northern hemisphere is home to craggy peaks. Rahnelo has a gravity that is slightly less than Sanghelios' gravity of 1.375 G. The du'nak are native to the planet.
In 2553, the defenseless Rahnelo was attacked by CRS-class light cruiser Spear of Light, commanded by Prelate Tem'Bhetek. The cruiser bombarded the planet's spaceport and bastion compounds, before deploying Jiralhanae infantry to the planet's surface to attack the colony's largest settlement. Rahnelo's residents were able to defend the head keep, but many Sangheili were killed by the Jiralhanae and Prelate. During the attack, Tem captured Kaidon Tulum 'Juranai and his two eldest sons, and left the system shortly after. In their absence, the kaidon's youngest son was given the title of kaidon over the settlement. Days later, CAS-class assault carrier Shadow of Intent arrived at Rahnelo, answering the planet's distress call. The attack on Rahnelo was to lead Shipmaster Rtas 'Vadum of Shadow of Intent into a trap at Duraan, which the Prelate subsequently attacked. However, 'Vadum and Tul 'Juran of Rahnelo were eventually able to locate and defeat the Prelate.
Government and society
The Sangheili of Rahnelo share a culture that is largely similar to that of Sanghelios. However, unlike on Sanghelios where Sangheili young seldom knew their fathers, Rahnelo's population was too small and clans were tighter knit to prevent the tradition from carrying on at Rahnelo. Like Sanghelios, only males could hold the title of kaidon; Tulum 'Juranai's youngest son became kaidon as a result, rather than his older daughter Tul 'Juran, the scion of Tulum 'Juranai's keep and captain of his guard. Native Sangheili spoke in the sharp, clipped cadence of Rahnelo's Sangheili dialect. Rahnelo was largely defenseless, with only local militias and bastion compounds protecting the colony. The Sangheili domesticated the native du'nak, and used them as beasts of burden or used their wool to create cloaks.
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