An aurora was a natural light display in the sky. It was caused by particles excited by energetic charged particles travelling along magnetic field lines into a planet's upper atmosphere. (COMIC: The First [+]Daniel McDaid, DWM Comics (Panini Comics, 2007).)
In northern latitudes this effect was known as the aurora borealis. Goronwy saw such an effect in the skies of Wales. (TV: Delta and the Bannermen [+]Malcolm Kohll, Doctor Who season 24 (BBC1, 1987).) The Sixth Doctor compared the colourful sky of Capron to the aurora borealis. (AUDIO: The Macros [+]Ingrid Pitt and Tony Rudlin, adapted from The Macro Men, The Lost Stories (Big Finish Productions, 2010).)
In southern latitudes this effect was known as the aurora australis. The Tenth Doctor and Martha Jones visited Antarctica in 1915 to watch the aurora australis, (COMIC: The First [+]Daniel McDaid, DWM Comics (Panini Comics, 2007).) while the Twelfth Doctor and Clara Oswald later saw it after their adventure involving Dr Patricia Audley and her immoral experiments. (COMIC: Blood and Ice [+]Jacqueline Rayner, DWM Comics (Panini Comics, 2015).) The aurora australis was also visible when the First Doctor, the Twelfth Doctor and Archibald Hamish Lethbridge-Stewart met in Antarctica, and when the three, along with Bill Potts, escaped from Testimony's spaceship. (TV: Twice Upon a Time [+]Steven Moffat, Doctor Who Christmas Special 2017 (BBC One, 2017).)
During his first visit to Vortis, the First Doctor saw lights in the sky which looked like the aurora borealis. (PROSE: The Lost Ones [+]The Dr Who Annual 1966 (Doctor Who annual, 1965).) On a subsequent visit, both he and Ian Chesterton saw these lights, the latter also comparing it to the aurora borealis. (TV: The Web Planet [+]Bill Strutton, Doctor Who season 2 (BBC1, 1965).)
The Fourth Doctor and Sarah Jane Smith visited to the Sigimund Galaxy to watch the aurora arctialis, which was caused by three suns. (COMIC: The Traitor [+]Doctor Who Annual 1978 (Doctor Who annual, World Distributors and Ltd, 1977).) In an alternate universe, Omega saw the aurora arctialis. (PROSE: The Infinity Doctors [+]Lance Parkin, BBC Books (1998).)
The Tenth Doctor and Rose Tyler visited to Serac to see its aurora. (COMIC: The Betrothal of Sontar [+]John Tomlinson and Nick Abadzis, DWM Comics (Panini Comics, 2006).)