Humans have long imagined the kinds of creatures or peoples that might live on Earth's moon. This section briefly describes ideas about lunar life in the 17th, 19th the 20th centuries through a series of items from the Library of Congress' collections. By examining ideas about life on the moon, insights emerge about the interplay between imagination and rigorous thought in our developing understanding of the universe.

The Peoples of the Moon in 1638

Publication of Galileo's telescopic observations of the moon had an important effect on ideas about life on other worlds. The idea that the moon was a physical place, a world like the Earth, suggested that the moon could be inhabited by beings much like us. In this vein, in The Discovery of a World in the Moone (1638), English bishop John Wilkins, suggested it"tis probable there may be inhabitants in this other World." In 1638 another Englishman offered a fictional account of a visit to just such an inhabited moon.

Francis Godwin's The Man in the Moone, published in 1638, follows the exploits of Domingo Gonsales, a Spanish noblemen who after a series of adventures on Earth makes a voyage to the moon. After exploits in the East Indies, Gonsales finds himself on the island St. Helena where he discovers a species of swan like birds. Realizing these birds can carry an extraordinary amount of weight; Gonsales creates a harness system that he uses to fly around the island.  He tries to fly back to Spain, but the birds keep flying higher and higher, taking him all the way to the moon. When he lands he finds there is a whole new world there, which he refers to as another Earth.  It's a place with plants, animals, and most surprisingly, a utopian civilization of tall, Christian people.

From the moon, Gonsales observes the Earth moving through the sky. This shift in perspective is helpful for thinking about the relationships between heavenly bodies. Looking up at the sky from the moon's surface, it is the Earth that moves through the sky. Describing this frame of reference helps explain how a world (like the moon or the Earth) could be in motion yet seem like all the other heavenly bodies were moving around it.

Astronomers like Copernicus, Brahe, and Kepler had dismantled many of the components of Aristotelian framework for the cosmos.  One of the results is that the planets became physical places. The planets (and the moon) changed from being perfect celestial objects to being worlds like the Earth.

Flying Bat People on the Moon?

In 1835 the New York Sun published 6 articles describing the discovery of various species of creatures inhabiting the moon. Allegedly written by Dr. Andrew Grant, the stories claimed to report on recent discoveries from the prolific astronomer John Herschel. The articles were in fact written by Richard Locke, a reporter working for the New York Sun. In the articles, Herschel is alleged to have observed creatures that look like bison, goats, unicorns, and tail-less beavers in forests on the moon. The most stunning find, however, was the discovery of human-bat creatures who had constructed temples on the moon.

These stories brought considerable attention to the New York Sun. People around the world were interested in learning about the inhabitants of the moon.

Several weeks after publication these stories were dismissed as "The great moon hoax." However, if the public had responded differently it might just as well have become the "the great moon satire." The believability of the stories in their time speaks to ideas about the possibility of life on the moon in the 19th century.

In scientific circles the notion that there could be sophisticated life on the moon was quite plausible. John Hershel's father, astronomer William Hershel, had worked to document life on the moon. In 1778 William Hershel believed he had observed lunar towns, but by the 1830's observations of the moon were making it less likely that there were lunar civilizations.

Popular science writers continued to insist that the moon was inhabited.  In 1838, Thomas Dick, a popular writer on Christianity, philosophy and astronomy wrote ,"the Moon is inhabited by rational creatures, and that its surface is more or less covered with vegetation not dissimilar to our own Earth" and that from a telescope one can observe "great artificial works in the Moon erected by the lunarians." Similarly, the 1846 textbook The Young Astronomer External explained, "It is the general opinion of astronomers that the Moon is inhabited." In popular writing throughout the century authors suggested that life on the moon was practically a fact.

Richard Locke, the author of the stories that have come to be known as the "moon hoax", insisted that the stories were intended as satire. According to him, his goal was to lampoon what he thought were absurd ideas about lunar civilizations being presented as science by writers like Thomas Dick. The fact that this satirical account would become a hoax itself illustrates that at the time it was a plausible assumption that there was life on the moon. What he thought would be read as an absurd joke was largely accepted and believed as scientific fact.

Continued Interest in Life on the Moon

As more powerful telescopes and other techniques for modeling the gravity and atmosphere of the moon were developed it became harder and harder to support the idea that the moon could be an Earth like place. After recounting all of the reasons life on the moon is unlikely, a 1915 astronomy textbook notes, "Even with all this, still life in some weird form may exist on the Moon External." Indeed, ideas about weird forms of life on the moon found their way into science fiction.

H.G. Wells' 1901 novel The First Men in the Moon offered just such a weird form of life. Set in England, the story is narrated by a London businessman, Mr. Bedford who meets up Mr. Cavor, an inventor who created a new material called cavorite that negates the force of gravity. Mr. Cavor persuades Bedford to use this material to go on a trip to the moon with him. When they arrive on the moon it appears to be a barren wasteland until they meet Selenites, the insectoid lunar natives who live inside the moon. Both men are captured by the Selenites, but manage to escape. After their escape, Mr. Cavor is recaptured and Bedford returns to England. While the evidence had mounted for a barren lunar landscape, people were still interested in a good story about the kinds of strange life that could exist beneath its surface.

Biological Interest in the Moon and the Apollo Missions

In the 20th century, as the possibility of travel to the moon became reality in the Apollo missions, scientists explored the remaining possibilities what kinds of life could exist on the moon. For example, Carl Sagan wrote on the possibility of lunar organics as part of his doctoral thesis. When it came time to train Apollo astronauts regarding what they might run into on the moon, Sagan was chosen, along with other scientists, and the science fiction author Isaac Asimov, to develop a curriculum for them on the possibilities of lunar organic materials. The procedures for quarantining astronauts who return from the moon was in part shaped by Sagan's and other scientists work outlining the possible effects of organic material and microorganisms on the moon.

Persistent Notions of Lunar Life

As the Apollo missions advanced toward landing humans on the moon, fanciful ideas about exotic intelligent life forms on the moon persisted in popular culture.

Even Dick Tracy was discovering lunar civilizations. The comic strip, which began by following the tough but honest detective in 1931, brought in characters from the moon in the 1960s. In 1964 Dick Tracy rode a "space coupe" to the moon and on his visit discovered an advanced civilization. The daughter of the Governor of the moon, the Moon Maid became the liaison to Earth and a frequent character in the strip in the mid 60s. The Moon Maid married Tracy's adopted son, and gave birth to a child half way between the Earth and the moon.

As the real world moon landing came closer and closer to reality, the stories of the moon and the Moon Maid were largely left behind in the comic. Dick Tracy returned to stories of terrestrial crime fighting. The more we learned about the actual conditions on the planets with subsequent space exploration the less sustainable the fantasy of intelligent life in our solar system became.