Mai Kondo

Mai Kondo was a 52nd century alien environmental science student. The Tenth Doctor met her on Winter Wonderland, where she accidentally surfed into the TARDIS. She was on the planet for her thesis. The Doctor took her to 1814 to see the beginning of the Industrial Revolution. To save the Earth from a Hyban looking for energy, they brought it back to Winter Wonderland, where its natural cooling abilities could counteract the rising temperatures due to the planet's orbital decay. (PROSE: The Frozen)