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Jyotisha is one of the six Vedangas, the auxiliary limbs of the Veda, and is traditionally called the eye of the Veda: the limb by which ritual finds its hour. Mesha is where its solar year begins, which makes it the sign most often read from a temple noticeboard rather than a chart.

Its lord Mangala is worshipped as a deity, not treated as a symbol. He is Angaraka, "the burning coal", and Bhauma, son of the earth-goddess Bhumi; his day is Tuesday, his colour red, his offering red lentils and red cloth. Mangalnath at Ujjain is held in tradition to be his birthplace, and Vaitheeswaran Koil in Tamil Nadu is his temple in the nine-temple Navagraha circuit of the Kaveri delta. In most South Indian temples he stands in the Navagraha shrine, nine figures in a grid around Surya, each facing its own direction and circumambulated in turn. Where a chart shows him afflicted, the classical remedies are graha shanti — japa of his mantra, homa, a Tuesday fast, donation of his grain and metal — and in popular practice the recitation of the Hanuman Chalisa.

The sign's nakshatras carry their own deities:

Nakshatra	Padas in Mesha	Deity	Graha
Ashwini	1–4	the Ashvini Kumaras, twin physicians of the gods	Ketu
Bharani	1–4	Yama, lord of the dead and of restraint	Shukra
Krittika	1	Agni, the fire that carries offerings	Surya

In muhurta, the election of auspicious time, Ashwini is prized for beginnings, journeys and medicine; Bharani, under Yama, is avoided for weddings and housewarmings. A horoscope is cast at the samskaras: at Namakarana the child's first syllable is taken from the pada of the Moon's nakshatra — Chu, Che, Cho and La for the four padas of Ashwini — and at Annaprashana, Upanayana and Vivaha the hour is chosen the same way. Mesha matters in marriage matching through the Bhakut kuta, one of the eight kutas scored out of thirty-six, and Mangala's placement raises the question of Mangal dosha, the single most-checked affliction in Hindu matchmaking.

Date	Event	Note
c. 1400–1200 BCE	Observations behind the Vedanga Jyotisha	Inferred from solstice positions; disputed.
c. 700–500 BCE	Vedanga Jyotisha of Lagadha	Earliest surviving Indian astronomical text. Range disputed; it has nakshatras but no rashis.
c. 2nd–3rd c. CE	Yavanajataka, Greek transmission	The twelve-sign zodiac enters Sanskrit. Pingree dated it 269/270 CE; Mak (2013) disputes both the date and the translation story.
499 CE	Aryabhata's Aryabhatiya	The computational basis for locating the Sun in a rashi.
6th c. CE	Varahamihira, Brihat Jataka and Brihat Samhita	Mesha's standard significations are fixed here.
c. 4th–10th c. CE	Surya Siddhanta	Wide, contested range.
~14 April, annually	Mesha Sankranti	The Sun's sidereal ingress, and the busiest solar-transit date in the Indian year.

Mesha Sankranti carries Vaisakhi in Punjab, a harvest day and a Sikh religious observance marking the founding of the Khalsa in 1699; Puthandu, the Tamil New Year; Vishu in Kerala, whose kani — the first sight on waking, arranged before an image of Krishna — is a domestic rite; Bohag Bihu in Assam; Pana Sankranti in Odisha; Pohela Boishakh in Bengal; and the Bikram Sambat new year in Nepal. Most are still kept as religious observances with temple visits and household ritual, not only as public holidays.

Mesha sits at the opening of the sidereal solar year, mid-April to mid-May — spring turning to heat across most of the subcontinent. It runs about twenty-four days behind tropical Aries, and the reason is precession: the March equinox slides westward along the ecliptic at roughly one degree every seventy-two years, so a zodiac pinned to the equinox has drifted about 24° from one pinned to the stars. Jyotisha keeps the stars and accepts the moving date; the Lahiri ayanamsa, India's standard since the 1955 Calendar Reform Committee, is the measure of that gap.

• Vedic Rashis
• World Zodiacs
• Aries — the tropical counterpart.
• Religion
• Calendar