Giant comets and human culture

Our understanding of Earth history on geological timescales is in a state of flux due to the realisation in recent years that the Earth is a bombarded planet. However recent findings suggest that a celestial input may also be important on much shorter timescales. Apart from the current hazard, the night sky in prehistoric times appears to have been dominated by a giant, short-period comet and its debris, and interactions with this material may have had a strong influence on human cultural development. This revised version was published online in August 2006 with corrections to the Cover Date.