Comet is a popular-science book by Carl Sagan

Carl Sagan

Carl Edward Sagan was an American astronomer, astrophysicist, cosmologist, author, science popularizer and science communicator in astronomy and natural sciences. He published more than 600 scientific papers and articles and was author, co-author or editor of more than 20 books...

 and Ann Druyan

Ann Druyan

Ann Druyan is an American author and producer specializing in productions about cosmology and popular science. She made substantial contributions to the PBS documentary series, Cosmos, and was the wife of late scientist and educator, Carl Sagan.-Film career:Along with Carl Sagan and Steven Soter,...

. It describes the scientific nature of comets, as well as their varying roles and perceptions throughout history. The evolution of human understanding of comets is also detailed, and thinkers and astronomers such as Edmond Halley

Edmond Halley

Edmond Halley FRS was an English astronomer, geophysicist, mathematician, meteorologist, and physicist who is best known for computing the orbit of the eponymous Halley's Comet. He was the second Astronomer Royal in Britain, following in the footsteps of John Flamsteed.-Biography and career:Halley...

, Immanuel Kant

Immanuel Kant

Immanuel Kant was a German philosopher from Königsberg , researching, lecturing and writing on philosophy and anthropology at the end of the 18th Century Enlightenment....

, and William Huggins

William Huggins

Sir William Huggins, OM, KCB, FRS was an English amateur astronomer best known for his pioneering work in astronomical spectroscopy.-Biography:...

 are discussed.

The publication of the book was months ahead of the 1986 appearance of Halley's Comet.