Symbols for the classical planets, zodiac signs, aspects, lots, and the lunar nodes appear in the medieval Byzantine codices in which many ancient horoscopes were preserved. In the original papyri of these Greek horoscopes, there was a circle with the glyph representing shine () for the Sun; and a crescent for the Moon.
The written symbols for Mercury, Venus, Jupiter, and Saturn have been traced to forms found in late Classical Greek papyri. The symbols for Jupiter and Saturn are monograms of the initial letters of the corresponding Greek names, and the symbol for Mercury is a stylized caduceus. A.S.D. Maunder finds antecedents of the planetary symbols in earlier sources, used to represent the gods associated with the classical planets. Bianchini's planisphere, produced in the 2nd century, shows Greek personifications of planetary gods charged with early versions of the planetary symbols: Mercury has a caduceus; Venus has, attached to her necklace, a cord connected to another necklace; Mars, a spear; Jupiter, a staff; Saturn, a scythe; the Sun, a circlet with rays radiating from it; and the Moon, a headdress with a crescent attached. A diagram in Johannes Kamateros' 12th-century Compendium of Astrology shows the Sun represented by the circle with a ray, Jupiter by the letter zeta (the initial of Zeus, Jupiter's counterpart in Greek mythology), Mars by a shield crossed by a spear, and the remaining classical planets by symbols resembling the modern ones, without the cross-mark seen in modern versions of the symbols.

The modern sun symbol, pictured as a circle with a dot (U+2609 ☉ SUN), first appeared in the Renaissance. (The conventional symbols for the signs of the zodiac also develop in the Renaissance period as simplifications of the classical pictorial representations of the signs.) The modern sun symbol resembles the Egyptian hieroglyph for "sun" – a circle that sometimes had a dot in the center, (U+131F3 𓇳 EGYPTIAN HIEROGLYPH N005). Similar in appearance were several variants of the ancestral form of the modern Chinese logograph for "sun", which in the oracle bone script and bronze script were . It is not known if the Egyptian and Chinese logographs have any connection to the European astrological symbol.
Symbols for Uranus, Neptune and Pluto were created shortly after their discovery. For Uranus, two variant symbols are seen. One symbol, , invented by J. G. Köhler and refined by Bode, was intended to represent the newly discovered metal platinum; since platinum, sometimes described as white gold was found by chemists mixed with iron, the symbol for platinum combines the alchemical symbols for iron, ♂, and gold, ☉. An inverted version of that same symbol, was in use in the early 20th century. Another symbol, , was suggested by Lalande in 1784. In a letter to Herschel, Lalande described it as "un globe surmonté par la première lettre de votre nom" ("a globe surmounted by the first letter of your name"). After Neptune was discovered, the Bureau des Longitudes proposed the name Neptune and the familiar trident for the planet's symbol, though at bottom may be either a cross or an orb . Pluto, like Uranus, has multiple symbols in use. One symbol, ♇, is a monogram of the letters PL (which can be interpreted to stand for Pluto or for astronomer Percival Lowell), was announced with the name of the new planet by the discoverers on May 1, 1930. Another symbol, popularized in Paul Clancy's American Astrology magazine, is based on Pluto's bident: .
The astrological symbols for the first four objects discovered at the beginning …

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