The Seven Sisters, also known as the Pleiades, were a group of stars visible from Earth. Once Ian Chesterton showed them to Vicki Pallister in the Earth sky and commented about their position related to Andromeda and Pegasus. (PROSE: Byzantium!) The Pleiades were visible from the planet Menda. When looking at the stars from Menda, the Eighth Doctor pointed out the Pleiades and Crab Nebula to Julya. (PROSE: The Janus Conjunction)