... Many of the brightest blue images are of a single, unusual, beaded, blue, ring-like galaxy which just happens to line-up behind a giant cluster of galaxies. ... M27: Not a Comet . ... Announcing Comet Catalina . ... Completing an orbit of the Sun once every 6.45 years, perihelion distance for this periodic comet is about 1.3 astronomical units (AU), still outside the orbit of planet Earth (at 1 AU). ... Dusty debris from periodic Comet Swift-Tuttle was swept up by planet Earth this week. ...