Data drops
From Halopedia, the Halo wiki
The data drops is are a six-part series of documents made by 343i to reference other Halo story material and establish links between them.
Data drop #1
The first data drop is very brief, and shows the star chart Dr. Catherine Halsey recovered from CASTLE base. The chart displays the position of Onyx, a planet officially nonexistant due to sensitive ONI research in the area.
Data drop #2
The second data drop is an email from Admiral Michael Stanforth to ONI chief Margaret O. Parangosky regarding the recent Battle of Sigma Octanus IV in July 2552. The end of the email establishes the admiral's knowledge of the Onyx and Reach artifacts and suggests a possible link between the three.
