Every Major Celestial Event
With the IQ Layer

Neither planet reverses. Retrograde is a line-of-sight effect: as Earth and a planet pass each other in their orbits, the planet appears to drift backward against the stars for a few weeks.

Babylonian scribes logged these stations in their Astronomical Diaries, and tied Mercury to Nabu, god of scribes. The Maya tracked Venus across its 584-day cycle in the tables of the Dresden Codex. The modern “communication breakdown” reading of Mercury retrograde is a 20th-century popularisation.

Leonids hit the atmosphere at about 71 km per second, the fastest of the major showers. In November 1833 the stream produced a storm of tens of thousands of meteors an hour over North America. Yale’s Denison Olmsted collected eyewitness reports through the newspapers and showed the meteors radiated from a point in Leo — the start of modern meteor science.

Lakota winter counts held by the Smithsonian record that winter as the one when the stars fell. Leo’s brightest star, Regulus, was “the King” in Babylonian star lists.

“Supermoon” is not an astronomer’s term. The astrologer Richard Nolle coined it in 1979; the technical name is a perigee-syzygy full Moon. The difference in size is real but modest, a few percent wider than an average full Moon.

The Pleiades the Moon passes were MUL.MUL, simply “the Stars”, and head the list of constellations on the Moon’s path in the Babylonian compendium MUL.APIN. “Beaver Moon” comes down through the North American almanac tradition.

Almost every major shower comes from a comet. The Geminids come from 3200 Phaethon, a rocky asteroid discovered in 1983 in data from the IRAS satellite, the first asteroid found by a spacecraft. It is named for the son of Helios who lost control of the Sun’s chariot.

This is also a young shower: reports begin only in the mid-1800s, so there is no ancient Geminid lore to quote, and we will not invent any. The radiant’s constellation is another matter. Gemini’s two bright stars were the “Great Twins” in Babylon and Castor and Pollux, protectors of sailors, to the Greeks and Romans.

The cause is Earth’s 23.4° tilt, not its distance from the Sun. “Solstice” is Latin for “Sun stands still”: the sunrise point on the horizon stops drifting south and turns back.

Newgrange in Ireland, Maeshowe in Orkney and Stonehenge’s midwinter sunset axis were all built around that turning point. In the tropical zodiac this is the moment the Sun enters Capricorn, which is how the Tropic got its name.

Full Moons near the December solstice climb highest in the northern sky, because the full Moon sits opposite the low winter Sun. That is why this one lights the night for so long.

“Cold Moon” and “Long Night Moon” are names from the North American almanac tradition. Astrologers place this full Moon in Cancer, opposite the Capricorn Sun.

The shower is named for Quadrans Muralis, the Mural Quadrant, a constellation introduced in 1795 and left out when the International Astronomical Union fixed the list of 88 constellations in 1922. The meteors kept the name. The radiant now lies in Boötes.

This eclipse belongs to Saros series 131. The Saros is a cycle of 18 years, 11 days and 8 hours after which Sun, Earth and Moon return to nearly the same geometry. Babylonian record-keepers found the pattern in centuries of eclipse observations; Edmond Halley gave it the name “saros” in 1691.

Mercury does not change direction. Earth and Mercury are both moving, and for about three weeks our changing viewpoint makes the planet appear to slide backward. Babylonian astronomers recorded planetary stations as routine data. The idea that the period disrupts messages and machines is a modern reading, widely popularised in the 20th century.

On equinox afternoons, shadows on the north staircase of El Castillo at Chichén Itzá form a rippling line that meets a carved serpent’s head. Whether the builders designed it that way is still debated by archaeoastronomers. In the tropical zodiac the March equinox defines 0° Aries, even though the Sun now stands among the stars of Pisces on that date.

The Moon’s shadow will pass over Luxor and Karnak, temple complexes raised to the sun god Amun-Ra. The eclipse belongs to Saros 136, the series that has produced the longest totalities of the last hundred years. Astrologers will place it in Leo, the sign the tradition gives to the Sun.