From Halopedia, the Halo wiki
The Elduros system is a planetary system located among humanity's Outer Colonies centered around the unstable star Elduros. The star is orbited by two planets, the second of which is the human Outer Colony of Aleria.
Shortly after Aleria was first colonized by the Unified Earth Government, Elduros ended a millennia-long period of low solar activity. The star's recommenced instability led to the rise of temperatures on Aleria, eventually leading to a drought in 2453 that is still ongoing as of 2556. The UEG has since abandoned the planet due to financial concerns, and Aleria is now under the control of various courier guilds.
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