HMS Magpie, the UK's newest commissioned warship, is carrying out a bathymetric survey near Portsmouth Harbour.
She will be spending the next few months analysing its seabed, to ensure it's safe for the enormous aircraft carrier HMS Queen Elizabeth.
The survey, being carried out by the vessel's Royal Navy personnel, is assessing whether there has been a change in the seabed ahead of the arrival of HMS Queen Elizabeth's sister ship, HMS Prince of Wales.
Approximately three and a half million cubic metres of clay, sand and gravel has already been excavated as part of improvements to the harbour costing around £100million.
Portsmouth Harbour is one of the busiest in Britain, seeing more than 230,000 vessels come and go throughout the year.
HMS Magpie and her crew have been given the task of ensuring new channels are clear.
They plan to survey the spot where the Mary Rose sank in a bid to recover any hidden artefacts from the famous Tudor navy ship.
They will also be searching for the remains of a French warship, that sank at the same time as the Mary Rose, to learn more about the Battle of the Solent.
HMS Magpie is the second smallest vessel in the Royal Navy's fleet. One of her predecessors was a frigate and the only vessel commanded by the Duke of Edinburgh during his naval career.
- Watch Richard Jones's report here.