Comet 67P/Churyumov-Gerasimenko, composite image. This comet is famous for being studied by the Rosetta spacecraft which entered orbit around it in September 2014. Comets are bodies of ice and dust that enter the inner solar system from the outer solar system. As they approach the Sun, the heat boils the ice, producing a coma around the nucleus, along with a tail stretching out behind it. This comet was discovered in 1969. It has an orbital period of 6.45 years. It reached perihelion (closest approach to the Sun) on 13 August 2015. These six images were obtained from September to November 2015.