From Halopedia, the Halo wiki
A kelguid is a kind of technology employed by the Covenant. Kelguids are interactive holographic star-maps used by navigators to plot journeys through slipspace. The Covenant developed the kelguid technology through reverse-engineering Forerunner equivalents.
Covenant Intrusion corvettes carried a kelguid. During the Battle of Seoba in 2526, the kelguid of the Worthy Silence was recovered by UNSC Task Force Yama, and later used by Doctor Catherine Halsey to find the Covenant supply world of Zhoist. When Halsey waved her hand inside the kelguid's projected hologram, she reported a "cold tingle" in her arm. Despite this, Fleetmaster Nizat 'Kvarosee believed that humans were not intelligent enough to operate the device.
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