The satellite picture shows a plume originating from the island's active crater known as Mt Curry, or sometimes also referred to as Mt Asphyxia. It is possible that the plume is created by lava flows in contact with sea water, as it appears to be mainly steam.
Not much else is known about the eruption, because the island is uninhabited and extremely remote and has no monitoring on the island. Most of the information about this eruption will rely on remote sensing (satellite observations). [less]