Iriya no Sora, UFO no Natsu(イリヤの空、UFOの夏lit. Iriya's Sky, Summer of the UFOs) is a Japanese sci-fi light novel series written by Mizuhito Akiyama with illustrations by Eeji Komatsu that centers on the relationship between Kana Iriya, a high school girl who has to fight alien invaders, and Naoyuki Asaba, a member of the school newspaper club and one of her few friends. There were four light novels published by MediaWorks under their Dengeki Bunko imprint; the series was once nominated for the Seiun Award. Later, a six-episode original video animation adaptation was created based on the novels; the DVDs were released in Japan between February 25 and July 29, 2005. Two sound novel video games for the Nintendo DS were released in Japan; the first in January 2007 and the second in October 2007.