X-Ray Pleiades . ... Credit T. Preibisch ( MPIfR ), ROSAT Project, MPE , NASA Explanation: The Pleiades star cluster is one of the jewels of the northern sky . To the unaided eye it appears as an alluring group of stars in the constellation Taurus , while telescopic views reveal cluster stars surrounded by delicate blue wisps of dust-reflected starlight . ... The green boxes mark the position of the seven brightest visual stars.) ... NASA Web Site Statements, Warnings, and Disclaimers . ...