From Halopedia, the Halo wiki
This memorial was a series of memorial plaques dedicated to deceased personnel of the Office of Naval Intelligence, located inside ONI Alpha Site. The memorial was destroyed when New Mombasa was glassed by the Covenant to uncover the Forerunner portal to the Ark.
The top of this plaque reads:
In honor of those men and women of Naval Intelligence who gave their lives in service of the UNSC in the war against the Covenant.
Below that it lists the names of many men and women:
The bottom states:
Their bold initiative, intrepid fighting spirit and unwavering devotion to duty in the face of certain death reflected great credit upon themselves and were in keeping with the highest traditions of U.N.S.C. Naval service. They gallantly gave their lives in defense of the human race.
The center plaque states the following from top to bottom:
SN: 03956-26127-PC +
At the top:
In honor of those men and women of Naval Intelligence who gave their lives in service of the UNSC at Reach.
Then it lists the men and women's names:
And at the bottom it states:
Their indomitable courage, inspiring initiative, and selfless devotion to duty in the great credit upon themselves and the U.N.S.C. Naval Service. They gallantly gave their lives in the service of the U.N.S.C.
The memorial has several conflicts with later media. For example, Preston Cole's date of birth is listed as April 4, 2484, when he was canonically born on November 3, 2470. The memorial also lists Michael Stanforth's birthday as July 3, 2486, which would mean he was an admiral at the age of seventeen, suggesting that it too is an error. Admiral Margaret Parangosky is listed on the memorial, even though she was not killed in the Human-Covenant War and plays a crucial role in the subsequent Kilo-Five Trilogy. Since all ONI personnel who had appeared in canon at the time of the game's release are listed on the memorial, one may assume that their commemoration on the memorial is an Easter egg instead of canonical evidence for their deaths.
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