The Song of Urania

We turn to the astronomy of Mesoamerica, with a particular focus on the Maya and Aztec. The central feature of their astronomy was a pair of interlocking calendars which regulated all aspects of life. The surviving Maya manuscripts also deal extensively with the motion of Venus, which may also have driven decisions to go to war. We also look at the famous Aztec Sun Stone, the 2012 phenomenon, and the fall of the Itzá Kingdom. NOTE: The Song of Urania will be going on hiatus and will return on the first full moon of 2026.

Aboriginal Australian societies are believed to be among the oldest continuous cultures on the planet. Some of their oral traditions appear to preserve a cultural memory of celestial events from multiple millennia in the past. Aboriginal Australians were also keen observers of the heavens and recognized phenomena both common and rare, from the solstices, to solar eclipses, to auroral sounds, and stellar variability.

After the fall of the Mongol Yuan Dynasty, the Ming Dynasty drove the few small Nestorian Christian communities in China underground and largely closed China off to foreigners. Only in the 16th century with the arrival of Portuguese traders did contacts with the West begin to be revived. The newly founded Jesuit order organized a mission to China led by Matteo Ricci. After finding his efforts at establishing a presence in the country stymied by the government, Ricci discovered that the key to securing a permanent Jesuit presence in China was his knowledge of Western astronomy.

After Wang Mang deposed the Han Dynasty and instituted his new Xin Dynasty, he needed to promulgate a new calendar to mark the occasion. One of his court astronomers, Liu Xin, developed a new calendar that integrated the lunar and solar cycles with the planetary cycles and imbued it with numerological significance. We then talk about how Huan Tan, another astronomer of the era, would have gone about measuring the lunar mansions.

We turn to the ways that the Chinese Emperor's astronomers predicted and interpreted eclipses, as well as the so-called "guest stars" that they occasionally reported observing in the skies. Then we discuss the role of the planets, particularly Jupiter. Towards the end we hear a few examples of astronomy in Chinese folklore.

We start to explore the relationship between the heavens and the Earth in Ancient China, along with the role of astronomers. One of the most important concepts in Chinese political thought to emerge from this was the Mandate of Heaven. Finally, we look at the oldest record of Chinese astronomy, the story of the astronomers Xi and Ho.

We delve into the contents of the Vedanga Jyotisha, the earliest Indian text to deal explicitly with astronomy. Then we turn to early Hindu cosmology and their explanations for various celestial phenomena, from the phases of the Moon to solar eclipses. Lastly, we briefly cover the unique cosmology of the Jains.

We take a break from the main narrative in honor of this month's blue moon and turn to a somewhat more frivolous topic — how the term "blue moon" came to mean the second full moon in a calendar month.

Before getting back into Egyptian astronomy proper, we start by looking at Nabta Playa, a site of megalithic activity in the Nubian desert during the late neolithic. Then we turn to the megaliths the Egyptians are best known for — the pyramids. The pyramids have remarkably precise alignments to the cardinal directions and the techniques the Egyptians used to set these alignments remains a mystery. Finally, we look at the largest of the pyramids, Khufu's pyramid, whose so-called ventilation shafts have a possible astronomical connection.

The oldest plausible astronomical artifacts known are African, as are many of the oldest megaliths, around 10,000 of which dot the Sahara and whose orientations are astronomical in character. We then briefly survey some of the creation stories and sky myths from a number of the peoples of sub-Saharan Africa. Finally, we turn to a few of the more unique calendars in the region.

In this episode we examine the work of two Roman astrologers to see how Roman astrology worked in practice: Marcus Manilius, who wrote Astronomica, and Firmicus Maternus, who wrote the Matheseos.

This month the full moon falls on Three Kings' Day, traditionally a day that celebrates the adoration of the magi, so we investigate the famous Star of Bethlehem story. Through the centuries there have been dozens of astronomical and astrological theories put forward as to what the Star of Bethlehem was. We look at a few of the more prominent theories and their shortcomings, finishing with what is plausibly the leading candidate, the astrological theory of Michael Molnar, though as we'll see, this explanation, too, is not without its problems.

During the half millennium of the Roman Era in Ancient Greece, only two astronomers made any major advances. At the beginning of the Roman Era, Posidonius measured the size of the Earth and discovered the relationship between the Moon and the tides. But the triumph of Greek astronomy came 300 years later with the intricate planetary model of Ptolemy, which stood unchallenged for some 1400 years.