From Halopedia, the Halo wiki
Xenoarchaeology is a form of archaeology concerned with the study of the physical remains of past—though not necessarily extinct—alien cultures. The UNSC is known to have practiced xenoarchaeology on various worlds occupied by the Forerunners in the past, such as Onyx, Heian, and Reach. Many of these sites were classified top-secret by the Office of Naval Intelligence. After the Human-Covenant War, many researchers in the universities of Edinburgh and Calcutta were hired by the ONI to investigate Forerunner relics.
Known practitioners of xenoarchaeology include Dr. William Arthur Iqbal, Esko Korpijaakko, Laszlo Sorvad, Luther Mann, and Sandra Tillson. There are only a handful of experts in the field of xenoarchaeology, most of whom are recruited by ONI.
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