Shackleton was treated as a hero on his return to England .
The increase of more than six degrees south from Scott 's previous record was the greatest extension of Farthest South since Captain Cook 's 1773 mark .
Shackleton was treated as a hero on Captain Cook 's return to England .
The increase of more than six degrees south from Scott 's previous record was the greatest extension of Farthest South since Captain Cook 's 1773 mark .