The moon is a reliable friend. It waxes and wanes on a regular schedule and helps us mark the passage of time. It lights up the night sky, glowing white and providing relief through the darkest hours. So it’s no wonder that, once upon a time, when the moon glowed red and disappeared during a lunar eclipse, humans were terrified.
The second blood moon of 2018 will occur on July 27. Before and after the moon is obscured completely for an hour and 43 minutes—the longest totality of the 21st century, NASA predicts—it will seem to bleed, glowing an eerie red. Now we know the strange occurrence simply means the moon is transiting through the shadow of our planet and not reflecting the light of the sun. And though we may find it amazing to observe, we mostly aren’t afraid that a lunar eclipse is a bad omen—except for those who believe a blood-moon prophecy in the Bible predicts the end of days.
Historically, however, the disappearance of the moon—and the accompanying bloody hue of a lunar eclipse—was experienced as extremely meaningful and disconcerting, according to the 1899 book, The Story of Eclipses (pdf) by George Chambers. In the chapter entitled “Eclipses of the moon mentioned in History,” Chambers tells the sometimes scary tale of blood moons over millennia.
The first record of a total lunar eclipse comes from China. It occurred on Jan. 29, in 1136 BC, Chambers writes, or “in the 35th year of Wen-Wang on the day Ping-Tzu.” He cites the Chou-Shu, or book of the Chou Dynasty for the record, saying it was found in 280 AD in the tomb of an emperor deceased for centuries.
This chronicle of early China’s Warring States Period found in the tomb of King Xiang of Wei that Chamber references is better known as the “Bamboo Annals” (竹書紀年 Zhúshū Jìnián). The text actually refers to a total lunar eclipse thought to have taken place in 1059 BC, during the reign of the last king of the Shang dynasty. Reportedly, the moon’s disappearance was regarded as an important omen, signaling to the vassal king Wen of the Zhou dynasty that it was time to challenge his Shang overlord.
On Aug. 27 in 413 BC, or the fourth year of the 91st Olympiad by the ancient Greek calendar, a lunar eclipse led to disaster for the Athenian army. The troops were in Sicily fighting Syracusan forces and doing poorly. Sickness broke out among the soldiers and their commander Niclas decided that the Athenians should leave the island. Plutarch, in his Life of Nicias, writes:
Everything accordingly was prepared for embarkation, and the enemy paid no attention to these movements, because they did not expect them. But in the night there happened an eclipse of the Moon, at which Nicias and all the rest were struck with a great panic, either through ignorance or superstition. As for an eclipse of the Sun, which happens at the Conjunction, even the common people had some idea of its being caused by the interposition of the Moon; but they could not easily form a conception, by the interposition of what body the Moon, when at the full, should suddenly lose her light, and assume such a variety of colours. They looked upon it therefore as a strange and preternatural phenomenon, a sign by which the gods announced some great calamity.
The calamity came to pass, as expected. Chambers protests, ”But only indirectly was it caused by the moon!” The Syracusan army captured the panicking Athenian soldiers before they could flee.
The 19th-century scholar and clergyman archdeacon Edward Churton tells a story of what may have been one of the first attempts to gain power with fake news. But the archbishop of Canterbury, Thomas Bradwardine—also known as Doctor Profundus—used astronomy to thwart the tricks of a witch.
As the story is told, one “fine summer’s night” in 1349, while the moon was suddenly eclipsed, a witch tried to take responsibility for its dramatic disappearance. Churton writes, “‘Make me good amends,’ said she, ‘for old wrongs, or I will bid the Sun also to withdraw his light from you.'”
Bradwardine, a mathematician and philosopher who had studied with Arab astronomers, wasn’t duped by the ruse. He was familiar with both solar and lunar eclipse predictions. Churton explains, “‘Tell me’, he said, ‘at what time you will do this, and we will believe you; or if you will not tell me I will tell you when the Sun or the Moon will next be darkened, in what part of their orb the darkness will begin, how far it will spread, and how long it will continue.'”
With this, Bradwardine proved that the greatest witchcraft and most powerful magic is knowledge.
In 1504, Christopher Columbus pulled off an eclipse trick not dissimilar to the one the witch attempted in the 14th century, using knowledge of the kind Bradwardine wielded to thwart her manipulations.
As Duncan Steel explains in his book Eclipse: The Celestial Phenomenon that Changed the Course of History, in June of 1503, a shipworm epidemic destroyed two of Columbus’s four ships, forcing him to land on the Caribbean island now known as Jamaica. The island’s indigenous Arawak people for six months fed the uninvited guests. Eventually, however, they grew annoyed and stopped wanting to give up their cassava and fish. Columbus’s Spanish sailors mutinied, massacred Arawaks, and stole food.
Columbus had to do something. Three days before a lunar eclipse was to occur on the night of Feb. 29, he told the Arawak chief his Christian god was angry because the locals were no longer being generous. Evidence of his god’s displeasure would be revealed in three days’ time, when the moon would disappear from the sky and turn red with fury. He based this on knowledge of a coming lunar eclipse, noted in the 15th-century astronomer Johannes Müller von Königsberg’s almanac with astronomical tables, which sailors relied upon.
Indeed, three days later, the moon disappeared and seemed to bleed. Terrified, the Arawaks came running to the Spanish ships laden with provisions and beseeching Columbus to intercede with his god on their behalf.
The Spaniard pretended to consider the requests while he waited in private for the moon to re-emerge from the Earth’s shadow. Finally, Columbus said he’d negotiated a peace, premised on the Arawaks continuing to feed the Spanish.
Nearly a year and a half after they landed on the island, the Spanish headed home. Soon after, the conquest of the Caribbean and the North and South American continents began in earnest. If Columbus hadn’t tricked the Arawaks, it’s possible neither he nor his crew would have made it back to Spain. The world might be very different today.
It’s unlikely that the July 27 eclipse will have a similarly dramatic effect on history. We can still hope for a colorful show like the one of Oct. 13, 1837. Chambers writes that the range of hues the moon displayed that night were “very remarkable.” The celestial orb went beyond blood moon, transforming from copper to sea-green to a neutral tint to silvery.