 Complete the following phrase:  Shackleton returned from the Antarctic having narrowly failed to reach the Pole, and this gave Scott the impetus to proceed with plans for his second Antarctic expedition. On 24 March 1909, he took the Admiralty-based appointment of naval assistant to the Second Sea Lord which placed him conveniently in London. In December, he was released on half-pay, to take up the full-time command of the British Antarctic Expedition 1910, to be known as the 