Now limping back to Tasmania from the Antarctic under limited engine power, the 79-member scientific crew of an Australian icebreaker has gotten a first-hand lesson just how isolated you can be and still be in touch with the world. In the early hours of 22 July, a major engine-room fire aboard the 3,900-ton Class A icebreaker Aurora Australis left it powerless in the dark Southern Ocean, just 100 nautical miles from the Antarctic coast. The research and supply ship was on a rare venture into the bitter-cold southern winter to do marine research.
Within minutes of the fire breaking out, vessel Captain Tony Hansen sent out a distress signal via the Inmarsat A satellite system to Hobart, Tasmania, headquarters of the Australian Antarctic Division and the ship's owner, P&O Polar Australia Pty. Ltd.
At the time, the Aurora Australis was located at roughly 65 degrees south latitude. That far south, the Inmarsat satellite system, positioned in geostationary orbit over the equator, hangs just 15 degrees above the horizon. That is still above the 5 degree "look angle" below which contact becomes difficult, said Peter Yates, communications engineer with the Australia Antarctic Division in Hobart. In addition to Inmarsat A, the Aurora also was equipped with smaller, more portable Inmarsat C and M communications equipment, as well as high-frequency radio, and VHF marine radios, he said.
But while instantaneous satellite communications helped the Aurora get the word out, the vessel was still in deep trouble. It was dead in the pack ice 1,300 nautical miles south of Hobart, with virtually no one around. Knowing about a crisis and being able to get help are two different things.
Luckily, the ship escaped life-threatening damage by the timely use in the engine room of halon gas, which starved the fire of oxygen. Nonetheless, the icebreaker's main engine was knocked out, and for 60 hours the boat was adrift at the mercy of the ice and the frozen ocean.
During that time, the Australian Antarctic Division contacted other member nations of the Antarctic Treaty through the group's Council of Managers of National Antarctic Programs. While this is usually handled via email, it so happened that members of the group were engaged in a routine annual meeting in Concepcion, Chile.
As a result, Australia quickly canvassed rescue possibilities, said Rex Moncur, director of the Australian Antarctic Division. Sadly, none of the options looked very appealing. Only one other Antarctic Treaty signatory country had a vessel anywhere near the Aurora and that ship would need about five days sailing time to reach it, Moncur said. While helpful to know about, the faraway presence of the other ship would have provided cold comfort had the fire or further problems forced the Aurora's crew to abandon ship, either in life rafts or via the ship's two helicopters.
The choppers probably would have flown to France's Antarctic mainland Dumont d'Urville base. However, the small helicopters were built for limited research trips around the ship and couldn't have carried all the 79 scientists and crew in one go. What's more, a lengthy trip in vulnerable helicopters might have been just as risky as staying with the ship, given how quickly Antarctic weather conditions can change.
The other alternative in a deepening crisis would have been for the crew to abandon ship and take their chances on the drifting sea ice, Moncur said.
While the Aurora Australis, like most Arctic and Antarctic vessels, is well-equipped to call for help -- however distant -- its communications arsenal will shortly be boosted by another major tool: Iridium. Though the Iridium low earth orbit (LEO) satellite system is having troubles of its own, it is scheduled to start wireless communications services in September. Calls will be made from pocket-sized, battery-powered handsets that transmit conversations through the passing necklaces of LEOS.
"With polar orbiting satellites, the birds will concentrate over the Arctic and Antarctic on each sweep, meaning there's likely to be more calling availability in Antarctica than there will be on the equator," Moncur said. Ironically, given the architecture of Iridium, the regions of the earth with the fewest people -- the polar regions -- will have the highest density of orbiting Iridium satellites overhead.
While Iridium is unlikely to replace Inmarsat A for critical communications, it is likely to become very useful for field personnel spread out over the Antarctic continent during the southern summer, when lugging around the much heavier equipment needed to use Inmarsat would be impractical, Moncur said.
"The distance, the temperatures, and the fact that there are very few people around -- all make the Antarctic region a very special environment," Moncur said.
