As they dropped robotic devices into the middle of the Indian Ocean, the closest people to the crew of sailboat Lady Amber were on the international space station.
This week, the self-described "rough group of sailors" arrived in Fremantle after a four-month journey from the boat's South African base during which they battled 7m seas, dodged cyclones and evaded pirates in the name of science.
The crew of five dropped the 2m Argo floats in seas so remote that research and cargo ships seldom go there. While deploying floats off the east coast of Africa, they were warned about pirates but on the way to Fremantle, they went 30 days without seeing another boat.
In all, they dropped 55 robotic floats, costing up to $20,000 each.
The robots feed data to satellites on water temperature, oxygen concentration and salinity in the top 2km of the ocean, used to inform sectors including agriculture, fisheries, oil and gas, and meteorology.
Capt. Peter Flanagan, along with partner and first mate Rika Botha, volunteered for the voyage out of passion for the marine environment. Ms Botha was so dedicated to the expedition that when she had to be taken ashore in Mauritius with a broken leg, she refused to hand over computer passwords so she wouldn't be left behind.
"I have been at sea for 48-odd years, so this (research) is the way we can give something back after what it has done for us," Capt. Flanagan said. "That's the message: one person, even one rough group of sailors, can make a difference."
Over 10 years, more than 3000 floats have been placed.
The CSIRO-funded Lady Amber project was part of the research by UNESCO's Intergovernmental Oceanographic Commission, which has a base in Perth.
WA Science Minister John Day said the Government recognised the Indian Ocean's importance and had provided $2 million to IOC in Perth.