Off on a Comet

In Jules Verne's 1877 science fiction novel Off on a Comet (originally titled Hector Servadac), a comet grazes Earth and sweeps away a handful of people and debris. The comet then travels through the solar system before eventually bringing its passengers back to Earth.

Synopsis

The story begins on January 1 of an unspecified year in the 1880s, near Gibraltar, when a comet named Gallia strikes the planet. Thirty-six people—French, English, Spanish, and Russian—are carried off on the chunk of territory torn away. Initially, they mistake the event for an earthquake. Soon, strange phenomena emerge: Captain Servadac’s adjutant, Ben Zoof, leaps 12 meters high; day and night cycle in just six hours; east and west are reversed; and water boils at 66 °C, revealing a thinner atmosphere and lower pressure.

The travelers spot Earth and its Moon but mistake them for an unknown planet. They explore by ship, also taken by the comet, and discover a mountain range blocking what they think is the Mediterranean. On the island of Formentera (formerly part of the Balearic Islands), they find French astronomer Palmyrin Rosette, who explains everything: they are on a comet he discovered a year earlier and predicted would hit Earth, but thick fog prevented anyone from believing him.

A later expedition measures Gallia’s circumference at 2,320 kilometers. Rosette calculates the comet’s mass at 209,346 billion tonnes using a spring scale and forty 5-franc silver coins (which weigh exactly 1 kilogram on Earth).

However, the scale’s owner, Isaac Hakkabut, had rigged it, so the result must be reduced by a quarter. The castaways cannot farm the barren comet and survive on animals left behind. The sea does not freeze despite sub-zero temperatures—until a stone is thrown in, at which point it instantly freezes into smooth ice for skating and sleigh sailing.

Old Earth rivalries persist: French and English officers claim authority, arguing over Spanish Ceuta, now an island. Servadac tries to occupy it but fails, discovering the English have already taken it and communicate with Gibraltar via optical telegraph.

Gallia reaches its farthest point and heads back to Earth. In early November, Rosette’s refined calculations show a second collision on January 1, exactly two years after the first. The group decides to escape in a balloon made from ship sails.