From Halopedia, the Halo wiki
Triangulation is the process of determining the location of a point by measuring angles to it from known points at either end of a fixed baseline, rather than measuring distances to the point directly. The point can then be fixed as the third point of a triangle with one known side and two known angles.
In the Halo universe
The possible triangulation of human carriers signals broadcast from Earth in antiquity was a major concern of Hypodermic-FXT-J, a document authored by Admiral Preston Jeremiah Cole. The document suggested that ONI Section II immediately begin Slipspace attentuated broadcasts of the signals from various locations to mask the location of Earth. Cole expanded upon this concern in UNSC Transmission 102482-02, sent to Admiral Michael Stanforth in 2531.
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