Somnium by Johannes Kepler

Somnium by Johannes Kepler is considered the first Science Fiction ever written. Kepler wrote this book in 1608 in Latin and it was published in 1634 posthumously. I found an English translation for this book and after having it on my TBR for years together, I finally read it.

If you are not sure who Kepler was, he was a German astronomer who developed the laws of planetary motion. Copernicus discovered that planets revolved around sun and that Earth was not the center of the Universe. Kepler figured out that the planets revolved in elliptical orbits and that all these orbits follow some laws of Physics. Somnium in Latin means “Dream”.

This book is about a dream that Kepler had. It’s about an Icelandic boy, Duracotus whose mother is a witch and can talk to spirits from moon. One such daemon is invoked and he tells them the story of voyage to moon, to an island called Levania. The book is pretty interesting to read as it was written at a time when they had very basic telescopes to observe moon, they had not even developed airplanes and forget about traveling to moon, people couldn’t even travel to another country by air. It must have required so much of out of the box thinking and imagination on the part of the author to have written a book about traveling to and living on the moon.

  • Kepler assumes that there must be water on the moon and that the living beings there lived in “hollow caverns and continuous caves” and “deep and wide valleys” in the ground. People back in 17th century had no idea about meteroids and craters so he came up with his own explanation about the craters on the moon I guess.
  • Even though he had no idea about escape velocity or rockets, he talks about gravity and this is how he describes leaving Earth which is so accurate – “he is spun upward as if by an explosion of gunpowder and he flies above mountains and seas”.
  • He also talks about the difficulties that come when you leave Earth’s atmosphere, which is also correct – “Then he will face new difficulties: Intense cold and impaired respiration”.
  • He even mentions air pressure from such a travel. He even talks about using some special sponges around nostrils to enable us to breathe where there is no air.
  • Far side of the moon. He even talks about it. How one side of the moon always faces Earth and the other side doesn’t. He calls the two hemispheres of moon, Subvolvans and Privolvans. “Privolvans are completely deprived of the sight of their Volva”. Volva here refers to Earth. If you didn’t know, this is the reason for seeing only one side of the moon from Earth always – “One side of the moon always faces Earth because of what’s called synchronous rotation. That is, the moon rotates, or spins on its axis, in the same length of time it takes to orbit Earth” (from Link).
  • He says that Earth would appear four times bigger on moon compared to the size of the moon as seen from Earth.
  • I especially loved the description of day and night on moon and what it feels like to see Earth rise up in the sky on moon. Our one month will correspond to their one day – which is marked by the rising and setting of Earth in their sky, according to him. According to today’s science, Earth goes through phases similar to moon phases that we see on Earth and he even talks about that.
  • He also talks about long nights and days on moon which makes sense since Moon takes a month to rotate on its axis.
  • He also goes in depth about the eclipses – what a partial eclipse or a total eclipse would look like when you are standing on the moon. There will be very frequent solar eclipses on moon according to scientists today.
  • He mentions that creatures living on moon must be of monstrous sizes and that they had short life span.

I found this video which shows how Earth looks like from the moon –

It is a very short book, just around 30 pages but it was a fascinating book. There isn’t much to the story but considering this was written by a man in 17th century, I was in awe. How brilliant must he have been to have calculated and come up with so many facts about moon when not even a reflecting telescope had been invented or gravity was discovered. Reflecting telescope was invented much later by Newton in 1668 and his work was based off of Kepler’s. People who read this book when it was just released must have found it so much more interesting and magical. I am always amazed by the inventors and scientists from ancient past who advanced science by leaps and bounds when we hardly knew anything about the world we lived in.

Do read it if you are fascinated by history of science or science fiction. I gave this book 4 stars.

From what I gather, Kepler’s notes about this story is missing from this edition of the book. I am not sure where to find them. I got this book just for my collection as I am a fan of collecting older science fiction novels. But I am glad I read it. It’s amazing and just blew my mind!

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