Four huge underwater volcanoes have been discovered off the coast of Sydney.
The discovery was made accidentally by scientists who were looking for lobster larvae.
The cluster contains four volcanoes, thought to be about 50 million years old and stretching across 20km. They are close to 5km underwater and were discovered using sonar mapping of the sea floor.
Professor Iain Suthers, a marine biologist at the University of New South Wales told Guardian Australia: “My jaw just dropped. I immediately said, ‘What are they doing there and why didn’t we know about them before?’ It really backs up the statement that we know more about the surface of the moon than our sea floor."
The discovery was made using Investigator, a new high tech sonar mapping research vessel which was introduced in Australia in 2014.
Unlike previous models, it is able to map the sea floor in 3D at any depth. The custom built ship cost $120 million to complete.