Juno was the third asteroid discovered, found by Karl Ludwig Harding in 1804. Its glyph is a sceptre crowned with a star, and unlike the symbols for Pallas and Vesta, which were proposed by other astronomers, this one was assigned by Harding himself, the discoverer, drawing on Juno's status as queen of the gods and her traditional emblem of royal authority. The sceptre and star appeared in the astronomical almanacs of the early nineteenth century alongside the glyphs for Ceres, Pallas and Vesta until the 1850s, when Encke's reformed numbering system in the Berliner Astronomisches Jahrbuch replaced individual symbols for newly found asteroids, though the original four kept theirs in reference use.
Juno's glyph, like the others, re-entered active astrological practice through Eleanor Bach's 1973 ephemeris of the four asteroids, which is the documented starting point for their sustained use as chart factors in Western astrology. Harding assigned the sceptre and star not long after Gauss and von Zach had already fixed symbols for Ceres and Pallas, so by the time Juno was named the practice of giving each new asteroid an individually designed emblem, rather than a bare number, was already an established custom among the small circle of astronomers involved in the search.