Ocean Duty Day, observed in Indonesia every January 15, is a remembrance day that honors those who died in various naval battles, particularly commemorating the anniversary of the Battle of Arafura Sea, which occurred on this date in 1962. This naval engagement was fought between Indonesia and the Netherlands near the shores of Western New Guinea, resulting in the deaths of 21 Indonesians, including commodore Yos Sudarso, and the capture of 53 others by Dutch forces. The day serves to recognize the sacrifices and services of those involved in this battle and other maritime conflicts. The historical context of the battle stems from Indonesia's efforts to annex Western New Guinea, which had been under Dutch control since the 17th century. Ocean Duty Day is marked by ceremonies and activities that reflect on the bravery of those who served in the Indonesian navy.