Binary opposition Binary opposition A nebular opposition (also binary system) is a pair of related terms or concepts that are opposite in meaning. Binary opposition is the system by which language and thought, two theoretical opposites are strictly defined and set off against one another. It is the contrast between two mutually exclusive terms, such as on and off, up and down, left and right. Binary opposition is an important concept of structuralism, which sees such distinctions as fundamental to all language and thought. In structuralism, a binary opposition is seen as a fundamental organizer of human philosophy, culture, and language. Binary
Contact binary (small Solar System body) Contact binary (small Solar System body) A contact binary is a small Solar System body that is composed of two bodies that have gravitated toward each other until they touch. This means contact binaries have odd shapes. Comet Churyumov–Gerasimenko and Comet Tuttle are most likely contact binaries. Asteroids suspected of being contact binaries include the unusually elongated 624 Hektor and the bilobated 216 Kleopatra and 4769 Castalia. 25143 Itokawa, which was photographed by the "Hayabusa" probe, also appears to be a contact binary which has resulted in an elongated, bent body. About 10–15% of near-Earth asteroids larger than 200 meters