August 22, NAME_1 moored at Kilo Wharf in Apra Harbor, Guam, for a four-day liberty port visit; Conducted a replenishment-at-sea with the USNS NAME_2 (T-AKE 3), while underway in the Philippine Sea, on Sept. 1; Conducted a replenishment-at-sea with the USNS NAME_3 on Sept. 5; Conducted a replenishment-at-sea with the USS Mustin on Sept. 7.

Perform the following actions:
Step1: Identify all events according to date from  the news.
Step2: Extract the following items for each event:
    - date
    - Subject 
    - Object 
    - Location
    - activity

The date must be extracted from the text.
Output each event in JSON format with the keys: "date", "subject", "object", "location", "activity".
If the information isn't present, use "unknown" as the value.