To some 21 June may have been just another Sunday but to the Royal Australian Navy it was significantly World Hydrography Day.
The day may not be marked by many, but its significance is not lost on professional mariners.
Coordinated by the International Hydrographic Organization, the day highlights the important role that hydrography plays in our day-to-day lives.
The theme this year was ‘Our seas and waterways - Yet to be fully charted and explored' and concentrated on the fact that much of the world’s oceans, seas and navigable waters still remain unsurveyed.
There are higher resolution maps of the moon and Mars than for many parts of seas and coastal waters.
HMA Ships Paluma and Mermaid from the Australian Navy's Hydrographic Service embarked on a 12 week survey deployment leaving Cairns in early May to assume survey operations on Australia's North-West Kimberley coast.
Using state-of-the-art hydrographic survey equipment and processes, the ships ensure that the accuracy and adequacy of today’s charts reflect the seafloor bathymetry.
Commanding Officer Paluma Lieutenant Commander Peter Locke said his ship’s company marked their special day on passage from Darwin to Troughton Passage survey grounds.
"The purpose of the survey is to facilitate the safe navigation of coastal shipping transiting through the area," he said.
"In recent years the Kimberley coast has become an eco-tourist Mecca for boaties, yachties and cruise ship operators.
"The region caters for those that want to experience one of Australia’s last wilderness frontiers in its rugged and largely untouched beauty."
Troughton Passage lies between East Holothuria Reef and Bougainville Peninsula.
"The Kimberley coastline has a distinctively French and English feel due largely to the works our of ‘marine surveying’ forebears, namely; the Royal Navy’s Phillip Parker King and the lesser known, yet highly accomplished, French explorer Nicolas Baudin.
"Paluma and Mermaid are doing their bit to realise this year's theme by continuing the works of these early marine surveyors some 200 years later," he said.
This survey will ensure mariners can safely navigate the Kimberley coast using a tangible and superior product that will remain applicable for a further 200 years.