This is nuts. It looks like a whole chunk of the island, including much of the volcano's cone itself, has subsided into the ocean.
This is a view into the (now, it seems, non-existent) crater from the rim that I took in more a more peaceful 2012:
Shot from nearby Rakata:
We are a group of people who share an interest in walking, trekking, hiking, bushwalking, tramping, rambling, trail running, camping, climbing, mountaineering, and other outdoor adventuring!