China started its 21st Antarctic expedition Monday hoping to beat other countries to arrive at "the inaccessible pole" by land.

A total of 146 people boarded the Xuelong ship at Shanghai's Minsheng Lu Dock to kick off the 150-day expedition.

The major goal is to climb the highest icecap of the South Pole, said Wei Wenliang, a senior official with the Chinese Arctic and Antarctic Administration.

Other research that will be undertaken include investigating the psychological environment of the polar ocean, and data collection of polar bio-ecology and physical oceanography.

It is the 11th polar exploration trip for Xuelong, a polar science research ice-breaker. This one, however, is considered to be its most difficult mission to date, said sources with the State Oceanic Administration during the send-off ceremony.

The ship will also travel through westerly winds in areas where huge crests and gales are likely to test the staff on board.

"This expedition is going to be a milestone in the history of China's Antarctic exploration," Wei said.

Chinese scientists plan to conduct scientific experiments on the peak of Dome A and collect some ice samples. They will also put up a temporary weather observatory there.

Located far away from the coastline in the interior Antarctica, Dome A has a rigorous climate and a dangerous reputation. It has been named "the inaccessible pole."

The average temperature is minus 50 C in summer and minus 70 C in winter.

If the expedition is successful, China will be the first country to enter the area by land.