M2SL Recovery Station
From Halopedia, the Halo wiki
The M25L Recovery Station was a UNSC medical station. This is the station that Spartan-117 and Sergeant Johnson went to for medical checkout and debriefing after the events on Installation 04, and Operation: FIRST STRIKE. It is probable that Spartan-043, Spartan-104, and Spartan-058 recovered on this station as well.
Cassandra, a former Spartan soldier too wounded to continue active duty, lived on M25L. She wrote to Spartan-117 several times[1].