Currently it is northern winter on Vesta, and the northern polar region is in perpetual darkness.

FORBES: Stunning Photos of Vesta from Dawn

Nonetheless, at this time, the polar region would have been covered in forest.

BBC: Giant camel fossil found in Arctic

The five-week cruise set off on July 4 and is now in the sub-polar region of the North Atlantic between Greenland and Iceland.

CNN: Could volcanic eruptions signal boom time for ocean life?

Russia has updated a nuclear-submarine fleet, partly based in an Arctic port, and Canada has talked of beefing up a military presence in its vast polar region.

WSJ: Arctic Body Weighs China's Bid to Observe

Usually, the prevailing south-westerly wind would take the ash cloud away from Europe and over the polar region, but a high-pressure area is bringing it over Europe, where it is sitting and barely moving as the ash spreads.

BBC: Volcano cloud threatens Formula 1 preparations

The Arctic's importance has gained extra strategic and economic significance as melting ice in the polar region strengthens the feasibility of nations to use the Northern Sea Route (NSR) across the top of Russia and the Northwest Passage through Canada's Arctic archipelago.

CNN: China eyes Arctic options in energy, transport

"Climate change in polar regions is expected to be among the greatest of any region on the Earth, and it will cause major physical, ecological, sociological and economic impacts, " Dr Toepfer said.

BBC: Ice surprise for sailor