A vast "raft" of volcanic rocks stretching over 150 sq km (58 sq miles) is drifting through the Pacific Ocean, scientists say.
The sea of pumice - the size of 20,000 football fields - was first reported by Australian sailors earlier this month.
Experts say the mass likely came from an underwater volcano near Tonga which erupted around 7 August according to satellite images.
Image: MICHAEL HOULT Image caption Sailor Michael Hoult was one of the first to report the volcanic rock raft
