Canals Alleged straight-line markings on Mars found not to exist by spacecraft visits to Mars. Captured moons Satellites that did not originate in orbit around a planet but were captured into orbit from interplanetary space. A theory of origin of a planet-satellite or binary star system in which one body captures another body by gravity. Carbonaceous material Black material rich in carbon and carbon compounds, found in carbonaceous chondrites and believed to color many black comets and asteroids of the outer solar system. A series of nuclear reactions in which hydrogen is converted to helium, releasing energy in stars more massive than about 1.5 M .
Carbon is used as a catalyst.
The most prominent gap in Saturn's rings. An early scientific school which held that most features of nature formed in sudden events, or catastrophes, instead of by slow processes. Cause of eclipses The falling of a shadow of one body onto another body. The projection of the Earth's equator onto the sky. The projections of the two poles of the Earth's rotation onto the sky.