The Aurora was an energy being that came to Earth after the Ninth Doctor's crash. They were made of charged plasma. They needed to regularly get energy. The Doctor told them to not feast on Fridtjof Nansen and Hjalmar Johansen due to their historical significance. They fixed the TARDIS and left to explore the universe. (AUDIO: Northern Lights [+]Robert Valentine, Pioneers (The Ninth Doctor Adventures: Series 3, Big Finish Productions, 2023).)
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