Planetary symbols

Ma 540)[2] shows the seven planets represented by portraits of the seven corresponding gods, each a bust with a halo and an iconic object or dress, as follows: Mercury has a caduceus and a winged cap; Venus has a necklace and a shining mirror; Mars has a war-helmet and a spear; Jupiter has a laurel crown and a staff; Saturn has a conical headdress and a scythe; the Sun has rays emanating from his head; and the Moon has a crescent atop her head.

The written symbols for Mercury, Venus, Jupiter, and Saturn have been traced to forms found in late Greek papyri.

[4] A diagram in the astronomical compendium by Johannes Kamateros (12th century) closely resembles the 11th-century forms shown above, with the Sun represented by a circle with a single ray, Jupiter by the letter zeta (the initial of Zeus, Jupiter's counterpart in Greek mythology), Mars by a round shield in front of a diagonal spear, and the remaining classical planets by symbols resembling the modern ones, though without the crosses seen in modern versions of Mercury, Venus, Jupiter and Saturn.

According to Maunder, the addition of crosses appears to be "an attempt to give a savour of Christianity to the symbols of the old pagan gods.

"[5] The modern forms of the classical planetary symbols are found in a woodcut of the seven planets in a Latin translation of Abu Ma'shar al-Balkhi's De Magnis Coniunctionibus printed at Venice in 1506, represented as the corresponding gods riding chariots.

[8] A related usage is for the 'worker' or 'neuter' sex among social insects that is neither male nor (due to its lack of reproductive capacity) fully female, such as worker bees.

[10][e] Arising from the biological convention, the symbol also came to be used in sociological contexts to represent women or femininity.

This gendered association of Venus and Mars has been used to pair them heteronormatively, describing women and men stereotypically as being so different that they can be understood as coming from different planets, an understanding popularized in 1992 by the book titled Men Are from Mars, Women Are from Venus.

It possibly represents Apollo's golden shield with a boss; it is unknown if it traces descent from the nearly identical Egyptian hieroglyph for the Sun.

[10] The symbol dates from at latest the 11th century, at which time it was an arrow across or through a circle, thought to represent the shield and spear of the god Mars; in the medieval form, for example in the 12th-century Compendium of Astrology by Johannes Kamateros, the spear is drawn across the shield.

Salmasius and earlier attestations show that the symbol for Saturn, ♄, derives from the initial letters (Kappa, rho) of its ancient Greek name Κρόνος (Kronos), with a stroke to indicate an abbreviation.

[10] By the time of Kamateros (12th century), the symbol had been reduced to a shape similar to a lower-case letter eta η, with the abbreviation stroke surviving (if at all) in the curl on the bottom-right end.

Claiming the right to name his discovery, Urbain Le Verrier originally proposed to name the planet for the Roman god Neptune[25] and the symbol of a trident,[26] while falsely stating that this had been officially approved by the French Bureau des Longitudes.

[30] Professor James Pillans of the University of Edinburgh defended the name Janus for the new planet, and proposed a key for its symbol.

[26] Meanwhile, Struve presented the name Neptune on December 29, 1846, to the Saint Petersburg Academy of Sciences.

The original planetary symbol for Pluto was , a monogram of the letters P and L. Astrologers generally use a bident with an orb.

Encke (1850) used symbols for 5 Astraea, 6 Hebe, 7 Iris, 8 Flora and 9 Metis in the Berliner Astronomisches Jahrbuch.

But by 1851, the spate of discoveries had led to a general abandonment of these symbols in favour of numbering all asteroids instead.