... Credit: Rogelio Bernal Andreo (Deep Sky Colors) Explanation: Have you ever seen the Pleiades star cluster? ... Also known as the Seven Sisters and M45 , the Pleiades is one of the brightest and closest open clusters. Hurtling through a cosmic dust cloud a mere 400 light-years away, the Pleiades or Seven Sisters star cluster is well-known for its striking blue reflection nebulae . ... Publications with keywords: dust - open cluster . Publications with words: dust - open cluster . ...