The mysterious debris, initially thought to be tar balls, began appearing on beaches in Sydney last monthThe composition of the mysterious balls that washed up on the shores of Australia last month has been revealed — and scientists say the truth is "much more disgusting" than they initially thought.

Scientists have solved the mystery of sticky black balls that began washing on beaches in Sydney, Australia last month. Thousands of the strange balls first began appearing in mid-October, including at the city's famous Bondi Beach,