Tula

Tula is the seventh rashi, the Vedic sign of the balance or scales, corresponding to Libra. In jyotisha it is ruled by Venus (Shukra), and it is the sign of Saturn's exaltation, where Saturn is held strongest. Its quality is movable (chara), the cardinal mode, and its element is air (vayu tattva). Jyotisha reads Tula through Venus's sense of proportion and the scales' weighing: relationship, fairness, agreement, and the balancing of one against another. As a sidereal sign it is fixed to the stars and sits roughly 24 degrees behind tropical Libra. Venus's rulership and Saturn's exaltation here are dignities shared with Western astrology, and both traditions treat Tula as the sign most concerned with partnership and equilibrium.

Tula, balance, translates the Greek zygon, properly the beam or crossbar of a balance rather than the whole instrument, so the Sanskrit broadens the image slightly in naming the scales as a complete object; the transmission runs through the Yavanajataka, a versification of a Greek astrological text of roughly the second through fourth centuries CE, built in turn on the twelve equal signs Babylonian celestial divination had fixed by the fifth or fourth century BCE, a scheme absent from the older Vedic corpus entirely. Tula is also the only rashi named for a man-made object rather than a creature, a distinction it shares with the equivalent tropical Libra; Venus's rulership and Saturn's exaltation here belong to the later classical layer codified in compilations such as the Brihat Parashara Hora Shastra of roughly the seventh or eighth century CE.

Sources Brihat Parashara Hora ShastraSage Parashara (attributed) with The Yavanajataka of SphujidhvajaDavid Pingree, Jyotihsastra: Astral and Mathematical LiteratureDavid Pingree

Shukra, Venus, owns Tula, the second of his two signs, and the house Tula occupies is read through his condition wherever he stands.

Shani, Saturn, is exalted in Tula, with the twentieth degree given as the exact point, and Surya, the Sun, is debilitated here, with the low point at the tenth. This is the exact inverse of Mesha, where the Sun is exalted at ten degrees and Saturn falls at twenty. The two signs are opposite one another, and the arrangement is deliberate: in jyotisha a graha's exaltation sign and debilitation sign always stand opposed, so the Sun and Saturn trade positions across the Mesha and Tula axis. A practitioner who has read one end of that axis has, in a formal sense, already read the other.

Saturn exalted in a sign of Venus is one of the placements the classical literature treats most favourably for Saturn, whose reputation elsewhere is severe. The reasoning given is the friendship reckoning: Saturn and Venus are counted as natural friends, so Saturn in Venus's sign is a guest on good terms rather than an intruder.

Three nakshatras cross Tula. Chitra supplies its last two quarters, Swati lies wholly within, and Vishakha contributes its first three quarters before passing into Vrishchika. Their vimshottari lords are Mangala, Rahu and Guru. Swati, ruled by Rahu and sitting at the middle of the sign, is the arc most often singled out in the classical texts for independence of movement, and its placement inside a Venus-ruled sign is a standing example of how the mansion and the sign are read as separate voices.