The study of Comet Halley in 1986 was a tremendous success giving a big boost to cometary science. In March of that year, six spacecrafts passed through Comet Halley as close as 600 km from the nucleus and made the "in situ" measurements of various kinds. These space missions to Comet Halley and that of the ICE spacecraft to Comet Giacobini-Zinner combined with studies, both ground-based and above the atmosphere, have increased our knowledge of cometary science in a dramatic way. This new edition of "Physics of Comets" incorporates these new and exciting findings. The emphasis of the book is...