Solar analog (–0.21) for solar twin. 16 Cygni B is sometimes noted as twin, but is part of a triple star system and is very old for a solar twin at over 9 Gyr. Another way of defining solar twin is as a "habstar" — a star with qualities believed to be particularly hospitable to an Earth-like planet. Qualities considered include variability, mass, age, metallicity, and close companions. The requirement that the star remain on the main sequence for at least 3 Ga sets an upper limit of approximately 1.5 solar masses, corresponding to a hottest spectral type of F5 V. Such
Battle for Terra won the Grand Prize for Best Animated Feature at the 2008 Ottawa International Animation Festival. Mala (Evan Rachel Wood) and her friend Senn (Justin Long) are young alien creatures who live on Terra, a planet from a star system in the Milky Way. Terra is a peaceful planet of alien creatures who have a rich semi-advanced culture. One day a large, mysterious object blocks the Terrian sun, piquing the Terrians' interest. However, since the Terrian culture bans the development of new technologies, such as telescopes, without the approval of the ruling council, none of the inhabitants are able to get