In this article I follow the mystery of millions of tons of materials washed out to sea by the March 2011 Japan tsunami: a massive wave of lost materials expected to reach North American shores that never seems to officially arrive. I bring Gordon's conceptualization of haunting together with STS conversations about absence and invisibility to build on feminist approaches that do not take as given what is missing or what should be done. I begin by situating efforts to respectfully distinguish materials survivors call 'floating things' amidst a sea of concern for ocean plastic pollution. These efforts are then contrasted with what I initially perceived as the institutional erasure of floating things at sea, re-counting how some practices work to ensure materials can be ignored, cleaned-up, or used for other kinds of ocean science research. Yet, floating things refuse to disappear completely, as potential traces wash up on beaches, trajectories are modeled back into existence, and individual practices exceed institutional obligations. I argue that attending to hauntings by listening to ghosts and drifting with them is necessary for justice-oriented forms of care for absences. In the case of floating things, this means honoring survivor relations while resisting the perpetuation of Pacific narratives of danger from the outside.
Keywords: absence; environmental monitoring; haunting; invisibility; materiality; memory; ocean plastic pollution.