Johannes Kepler (1571–1630)

Somnium is a fantastic blend of science and enchantment, perspectives that seemed to co-exist happily in the minds of the scientists of the 17th century. Kepler himself embodies that blend, as in the mixture of musical harmony and hard math behind “the harmony of the spheres” and his third law of planetary motion.

Somnium has been called the first science fiction novel, having been written in 1608 and published in 1634.

The story is a recounting of a dream. The narrator says that in his show more dream he was reading a book by an Icelandic man named Duracotus. Duracotus’s mother asks that a teacher she has known tell Duracotus of the island Levania.

The teacher tells about the journey up to Levania, our Moon, and about the nature of its two hemispheres, Subvolva and Privolva. Subvolva is so named because, from it, you can view Volva (Earth). Volva is stationary, not seen from Privolva and always seen in the same position in the Subvolvian sky.

The rest of the story is description — really the geometry of the Earth/Moon system, how it produces eclipses, the length of the Levanian day, and its seasons. And how all of these things generate the kind of life that is possible for the Levanians. It is a brilliant piece of imagination mixed with science.

Kepler knew of the Moon’s phases, its rotational period, its apparent size, and, placing all this into a larger geometry, he reached conclusions about how heat must build up during the long lunar day and how that heat must somehow be dissipated in order for life to be possible there. He concluded that “a serpentine nature is predominant,” with serpents living in caves coming out to expose themselves to the Sun but always able to retreat quickly back to the cool of their caves.

All of the story maintains a kind of descriptive distance — there are no adventures on Lavonia itself, just a description of its characteristics and large scale features, like a recitation of a body of scientific knowledge. But the knowledge is reached imaginatively and presented through the device of a dream.

To us, I think the inter-weaving of mysticism and science feels odd. I suspect it did not to Kepler, just as the combination of musical harmony and mathematics in the orbits of the planets is natural to him.

The book is very short (45 sparsely printed and unnumbered pages, with a very brief introduction). It doesn’t stand as an engrossing story in its own right, but is certainly interesting and provocative as an artifact of the time, and of the workings of a mind steeped in an amalgam of what we now separate into astronomy, alchemy, mathematics, and astrology. show less

This is a rather juvenile edition of an interesting work. I understand why Donahue feels the need to include large introductions and even paraphrases of obscure sections of the text. But replacing a proof by Kepler with an easier alternative - as Donahue does in Chapter 32 - is going too far. The only good use of this book is as a supplement to a full translation of the Astronomia Nova.

I just read this in the first edition, 1610, at the Houghton Library, Harvard. I was looking up Kepler's four references to Giordano Bruno, two in his Introduction (essentially half the 76pp) and two in the work itself. In the Intro Kepler mentions Bruno and Pythagoras together as positing other worlds--in relation to Galileo's observing "new worlds," the moons of Jupiter which he "sells" to the Florentine Medici as a worthy memorial, more worthy than a statue. Galileo calls the four moons show more he sees (out of 63 now identified) the "Medici Stars."
Kepler considers, what Bruno asserted, the possible inhabitation of the Moon. Kepler has a telescope, which Bruno never did. On the basis of observing the lunar surface, Kepler says, "If men live on the Moon, they must live in caves (speluncas), because their day is fifteen times as long as ours." show less

Easier to read than Huygens (perhaps the translation was better), but seemed the story was just the beginning of a much longer work, felt like it was cut short. Still, very amusing and entertaining quick read.
Duracotus from Thule. Levania (the moon).
Fiolxhilde, mother. Subvolva (side of the moon facing the earth), privolva (far side of the moon). Volva (the earth)
Sublovians and privolians are tall, live brief lives, but the latter are more wild than the former.