Comets

Ragnarok: The Age of Fire and Gravel

Ignatius Donnelly

Comet in Moominland

written and illustrated by Tove Jansson ; translated by Elizabeth Portch.

The Skies of Pern

McCaffrey, Anne.

In the days of the comet

H.G. Wells ; introduction to the Bison books edition by Ben Bova.

Now and Forever

Ray Bradbury

Magicians of the Gods: Updated and Expanded Edition - Sequel to the International Bestseller Fingerprints of the Gods

Graham Hancock

Hector Servadac

by Jules Verne

Centrifugal force and gravitation: a lecture

by John Harris.

What killed the dinosaurs?

by Isaac Asimov ; with revisions and updating by Richard Hantula.

L. Annei Senecae Naturalium quaestiunum libri VII.: Matthaei Fortunati in eosdem libros annotationes.

Seneca the Younger