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Gulliver's Travels

Seeing stars: Baffling astronomical knowledge from history

First edition of Gulliver's Travels in which Jonathan Swift accurately predicts the existence of Mars' two moons | Image: Wikipedia | Public Domain

From the discovery of Uranus in 1781 to the 2016 discovery of a galaxy 32 billion light-years away, the modern telescope has allowed humanity to explore more and more of the vast universe.

Mysteriously, there have been cases in history where a person or peoples have demonstrated knowledge of celestial bodies that they could not have seen, either with the technology they had or with the naked eye.

Here we explore several intriguing examples of such cosmic cognizance.

Swift's moons: The writer who predicted the Martian satellites

Anglo-Irish writer Jonathan Swift (1667-1745) is best-known for his 1726 fantasy Gulliver’s Travels. The novel follows the eponymous hero Lemuel Gulliver a ship’s captain and surgeon who finds himself in a series of strange lands after a shipwreck.

In Part III of the book, a marooned Gulliver is picked up by the tiny flying island of Laputa. The learned Laputans are keen stargazers and in one passage we are told how they’d observed two ‘satellites’ of Mars, with their distances from the planet’s surface and their orbital periods.

The two moons of Mars are Phobos and Deimos, and these were not discovered until August 1877 when Asaph Hall spotted them with a 26-inch refracting telescope.

How accurate was Swift?

Regarding the distance of Phobos from Mars, Swift’s prediction was out by more than double. The real average orbit distance (9,376 km) equates to about 1.4 times that of the planet’s diameter, while Swift gave a figure of three times its diameter.

Regarding Deimos’s distance, he was a bit more accurate, with the real average orbit distance (23,458 km) equating to around 3.5 times the planet’s diameter, Swift having given five times the diameter.

Regarding Deimos’s orbital period, the real duration is 30.3 hours. Swift gave 21.5. For Phobos, the real orbiting time is 7.6 hours. Swift gave 10 hours.

How did Swift know?

At the time Swift penned his famous novel, the two closest planets to the Sun, Mercury and Venus, were not known to have any moons (which they don’t). They knew of course that the next closest, Earth, had one moon, and astronomers up until that point had discovered four and eight moons respectively for the fifth and sixth in line from the Sun, Jupiter and Saturn. Estimating two moons for the fourth closest planet to the Sun, Mars, must have seemed in 1726 to be a good punt.

'Internal evidence suggests that Swift was no Martian...'

Carl Sagan

This way of thinking about the number of moons in the solar system originated with Johannes Kepler (1571-1630). It turned out to be true for Mars, but not as a rule of thumb for all the planets (Jupiter for example has far more than four moons – it has 79!).

It has also been pointed out by experts that if Swift believed in the existence of moons that couldn’t be seen, he would have inferred they were very small and very close to Mars, hence the great rapidity of Phobos.

However some writers have postulated the notion that Swift might have been a Martian.

Erich von Däniken (1935-) mentions Swift in his famous 1968 book on ‘alien astronauts’, Chariots of the Gods?, and Russian scientist V. G. Perminov even suggested that Swift may have stumbled across secret Martian records left on Earth.

American astronomer Carl Sagan poured cold water on the Martian idea in his 1973 book The Cosmic Connection: ‘Internal evidence suggests that Swift was no Martian, and the two moons can almost certainly be traced back to Kepler’s speculation.’

Despite the fame of Swift’s ‘prediction’ of the Martian moons (a crater on Deimos is named ‘Swift crater’) the author himself was scornful of astrology and in one famous event poked fun at astrologer John Partridge (1644-1714) by falsely predicting Partridge’s death in a letter written under the pseudonym, Isaac Bickerstaff.

Swift’s moons were likely a calculated guess rather than a prophecy of the variety made famous by French astrologer Nostradamus (1503-1566).

Harpoons and moons: The Efé people's esoteric knowledge

The famous Katanda harpoon, a ninety-thousand-year-old tool found in the modern-day Democratic Republic of the Congo, is believed to have been used by the ancestors of the Efé tribe to hunt catfish.

According to the Belgian anthropologist Jean-Pierre Hallet (1927-2004), who lived with the Efé in the 1950s, this group had long referred to Saturn as ‘the star of the nine moons’.

Saturn’s ninth moon was discovered in 1899, and then a tenth was spotted in 1966.

While the oral tradition of the extremely old Efé tribe should not be dismissed lightly, it does seem too much of a coincidence that they apparently knew how many moons Saturn had according to what was currently known by science at the time.

You cannot be Sirius: The Dogon people and Sirius B

One of the most well-known examples of ‘ancient astronauts’ literature is Robert Temple’s 1976 book The Sirius Mystery. Temple believed that Mali’s Dogon tribe may have had a long history of contact with intelligent aliens.

Central to this is the claim that the Dogon people had long known about Sirius B, a star discovered in 1862 and invisible to the naked eye. The Dogon’s chief priests had apparently told anthropologists in the 1930s and 1940s that the tribe had preserved ancient knowledge of the universe, and that the Sirius system was for them the focal point. They believed Sirius was the home system of the beings they called the ‘Nommos’. These were apparently amphibious extra-terrestrials that they’d worshipped in antiquity.

The Dogon apparently knew that Sirius B was very dense and that it took 50 years to orbit Sirius A.

While the Dogon mystery makes for a rollicking good story, it has been shown by scientists that the Sirius star system is highly unlikely to be harbouring any intelligent life. The prevailing view about the Dogon’s knowledge of Sirius B is that it came from modern French ethnographers.

I'm not Kidinnu: Did the Ancient Mesopotamians know about Axial precession?

Axial precession is the change in the angle of the Earth’s daily rotation, top to bottom, like a spinning top.

One way this change can be observed is by the pole star. Because the direction of where the North Pole is pointing changes one degree every 71.6 years, the role of the North Star passes from one star to another over time

The completion of this cycle - known as ‘The Great Year’ –takes 25,772 years.

Precession is generally thought to have been discovered by Greek astronomer Hipparchus (c. 190 – c. 120 BC).

There is a theory however that Chaldean astronomer Kidinnu discovered precession 250 years before Hipparchus, in the middle of the 4th century BC. This notion was championed by German historian Paul Schnabel (1887-1947) in the 1920s and was robustly disproved in subsequent decades by such experts as Otto Neugebauer.

Other writers – such as the authors of Hamlet’s Mill (1969) - have suggested that much more ancient peoples discovered precession, such as the Sumerians.

The seminal Sumerians flourished for thousands of years, between around 5300 BC and 1940 BC. Their astronomy and maths influenced later Mesopotamian civilisations and then the Ancient Greeks. They were keen on the number 60, giving us minutes and hours. It was also the ancient Sumerians who first began plotting constellations.

Proponents of the theory of Sumerian knowledge of axial precession argue that the ancient epic poem the Epic of Gilgamesh is in fact a history of astronomical events. The ‘battles’ described in the epic such as the slaying of the bull are said to signify a precessional change in the constellations, in this case from Taurus to Aries (which occurred about 1750 BC).

Today, the academic consensus is that nobody knew about axial precession before Hipparchus, and it was only scientifically calculated as recently as the 17th century, by Sir Isaac Newton.

While there is undoubtedly much more to learn about the Sumerians, the suggestion that they had knowledge of axial precession seems to be based on an interpretation of their mythology that doesn’t stack up.

While much of the literature mentioned here is quite rightly classed as pseudoscience, hypotheses such as these are still undeniably intriguing and thought-provoking. Ancient and primitive peoples clearly had a relationship with the night-sky that we still do not fully understand.