When Agarus was found in 2401, the explorers found numerous forerunner ruins and temples. ONI immediately red flagged the planet for colonization even though it was perfect for human life. In 2403 ONI began to construct dozens of science research and dig sites. By 2416 the research stations were complete and the scientists were brought in to reside in the bases while conducting their research. When the Covenant appeared in 2525 and they closed in on the inner colonies, ONI deployed numerous security teams to each of the research bases on the planet. In 2542 when an ONI security team went missing, ONI sanctioned the Spartans of Omega Company to investigate.