The sun has fired imaginations since the dawn of time, and is glorified by most religions. Were it to perish, our planet would be cast into chaos; but its reliable reappearance every day has shaped the diurnal rhythm of humankind. Distant and powerful, the sun has long inspired people to wonder whether its extraordinary force could be harnessed to travel outside the Earth’s sphere toward far-flung stars. At the same time, it is dangerous to get too close to the sun, as warned by the myth of Icarus, whose waxed wings were melted by its heatIn the field of statistical thermodynamics today, heat refers to the transfer of the thermal agitation of the particles making up matter... . Over the centuries, literature has recounted a number of poetic examples of humankind’s fascination with our closest star as a source of life and, as described below, a source of propulsion.
Cyrano de Bergerac
“I planted my self in the middle of a great many Glasses full of Dew, tied fast about me; upon which the Sun so violently darted his Rays, that the Heat, which attracted them, as it does the thickest Clouds, carried me up so high, that at length I found my self above the middle Region of the Air. But seeing that Attraction hurried me up with so much rapidity that instead of drawing near the Moon, as I intended, she seem’d to me to be more distant than at my first setting out; I broke several of my Vials, until I found my weight exceed the force of the Attraction, and that I began to descend again towards the Earth.”
Many years later, Edmond Rostand revisited the same idea, this time in verse. In a scene from the third act of his play Cyrano de Bergerac, the lead character tries to distract a passer-by by proposing a multitude of ways to travel to the moon, including the use of the sun and dew:
“I might, stripping my body bare as a candle,
have caparisoned myself with crystal phials
filled with the tears of the dawn skies, while
in exposing my person to the sunlight, too,
the star would suck me up as it does the dew!”
It is a method that scientists would scoff at, but, in a poetic sense, the idea stems from one of humankind’s most ancient dreams: flying.
De Graffigny and Jules Verne
As noted several times before in these articles, literature from the 19th century often allies scientific concepts with fantastical elements. Although the term “science fiction” had not yet been coined, the core concept was there. In France, these forward-looking works of fiction tend to be confused with the prodigious output of Jules Verne. But he was certainly not the only one writing in the field, and other authors who have been largely forgotten also deserve recognition, including Georges Le Faure (1856-1953) and Henry de Graffigny (1863-1934). Le Faure was a prolific writer mainly specializing in adventure novels, particularly swashbuckling stories. De Graffigny, on the other hand, is difficult to define. Often popularizing science – inspired by Camille Flammarion, whom he admired – he dabbled in everything from astronomy to electricityForm of energy resulting from the movement of charged particles (electrons) through a conductor... , farming and futuristic fiction. In all, he wrote more than 200 books, including the fantastical The Extraordinary Adventures of a Russian Scientist, a partly collaborative effort with Le Faure published between 1888 and 1896, making both authors French pioneers of science-fiction. The five-volume story recounts the adventures of Russian scientist Ossipoff, who is launched off Earth by a cannon to explore space (which obviously brings to mind Jules Verne’s From the Earth to the Moon). The novel is clearly inspired by astronomy and is in fact prefaced by Camille Flammarion, famed for his popular science works on similar topics. At the time of publishing, Le Faure and De Graffigny were already well known as writers. The work’s four parts, which could be bought and read separately, are The Moon (1889), The Sun and the Small Planets (1889), The Giant Planets and the Comets (1891) and The Sidereal Desert (1896), which was intended to be named The Worlds of Stars. In all four installments, elements of fantasy are combined with the scientific, rigorous precision of astronomical, physical and chemical data. In The Sun and the Small Planets, published in 1889, Le Faure and De Graffigny dream up a spacecraft that uses a vast mirror to harness the force of sunlight: “Five days after this conversation, the huge parachute of selenium surrounded the sphere, attached by cables to the sleeping room for the travelers. The sphere itself, suspended from two metal masts, was placed at the middle of the curved reflector. All that was left to do was to center the mirrors for liftoff the next day.”
Jules Verne had a similar idea in From the Earth to the Moon, where he refers to solar sails, a propulsion technology that uses radiation pressure exerted by stars to travel through space like on a sailing ship. In his novel, the writer suggests using this method to propel the characters’ spacecraft: “Because, though we are floating in space, our projectile, bathed in the solar rays, will receive light and heat. It economizes the gas, which is in every respect a good economy.” In doing so, Verne depicts environmentally friendly travel before its time.
Solar sailing is not just the product of fiction. The 20th century saw a few actual spacecraft produced using this technology, most notably Japanese solar sailing probe IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun). Such devices work on the principle of radiation pressure emitted by stars (the photoelectric effect). Large “sails” are used to drive forward (and steer) a spacecraft, but the energy harnessed is not enough to launch a ship beyond the pull of the Earth’s gravity. However, the solar sails can propel the spacecraft once in space. The most advanced project produced to date is the Japanese IKAROS probe, with 173 square meters of sails, which was launched in 2010 and is still continuing its mission. The solar sails help slightly increase the initial speed.
There are actually quite a few references to solar sails in science fiction, including the spacecraft which is suddenly detected near the Earth in Larry Niven and Jerry Pournelle’s The Mote in God’s Eye (1974), Pierre Boulle’s famous Planet of the Apes (1963), Il Etait une Voile Parmi les Etoiles (The Sail Between the Stars) by Jean-Louis and Doris Le May (1976), and Bernard Werber’s 2006 work Le Papillon des Etoiles (The Butterfly of the Stars), where, to escape humanity’s self-inflicted destruction, the protagonist boards a solar sailing spacecraft as part of the aptly named “Last Hope” project. The spaceship is designed to take tens of thousands of passengers to find another planet where well-meaning people can live. Solar sailing also plays a central role in Gérard Klein’s novel Les Voiliers du Soleil, even lending its name to the title, which means “The Solar Sailing Ship”. One passage describes this type of propulsion: “Because the big spacecraft was a solar sailing ship. It looked like a flower, a huge circle of blossoming, shining petals, several kilometers across. This flower was a sail. It couldn’t be more different from the square or triangular sails blown by earthly winds. There isn’t the slightest breeze in space. The only wind in this void is produced by the sun: light.”
Find out more:
The writing of Cyrano de Bergerac can be read online, with most of his works available in full (in French) on the French National Library’s Gallica site. However, they require a good amount of concentration due to now-outdated words and, in particular, 17th-century French spelling.
The quote on Cyrano’s flight experience can be found on page 44 of this edition.
The quoted works by Jules Verne and Henry de Graffigny can be accessed freely online. In particular, the full text of Le Faure and De Graffigny’s The Extraordinary Adventures of a Russian Scientist is worth a read: the tone is more comic than in the works of Jules Verne, sometimes close to derision. The focus of the scientific content is certainly astronomy, but not without a healthy dose of imagination. Although his work was highly popular during his own lifetime, De Graffigny is no longer a household name, undoubtedly because his reluctance to use a serious tone did not help retain readers.
Key information on the Japanese IKAROS experiment can be found on https://global.jaxa.jp/projects/sas/ikaros/. Lastly, a few classics of French science fiction, which often refer to solar sailing for crossing long distances with no other powerIn physics, power is the amount of energy supplied by a system per unit time. In simpler terms, power can be viewed as energy output... source but radiation pressure, can be found via https://fr.wikipedia.org/wiki/Les_Voiliers_du_soleil