Chandra married the 27 daughters (nakshaktras) of Prajapati Daksha. Chandra visited a Nakshatra each night in turn.
This story marks two astronomical facts. The night sky is divided into 27 nakshatras named after the prominent star in that section. The moon travels 13.3 degrees of the sky in each 24 hour period. Second, it marks the Sidereal (based on star) month, measured by the number of days it takes for the Moon to come back to the same Nakshatra, approximately 27 days.
The names of Nakshatras are the same in some of the oldest astronomical texts – Vedanga Jyotisha & Surya Siddhanta. The concept is ancient and like the Chinese concept of 28 lunar mansions. Greek & Mesopotamians did not have a direct equivalent.
The picture is a Wikimedia image of the 27 Nakshatras.

The star Rohini lies within 5 degrees of the Moon’s elliptic path (the apparent path that the moon takes when observed from the earth). As a result, the moon comes in front of Rohini more often than any other star. This is explained in puranas as Chandra’s excessive love for Rohini, at the cost of his love for his other wives. His other wives complained to their father Daksha, who then cursed Chandra. Ancient Indians observed this astronomical pattern and encoded the information through this story.
The sculpture is of Chandra and Rohini, Wikimedia

Daksha cursed the moon to die because he spent more time with Rohini and ignored his other 26 daughters. Chandra ran to Shiva for help. Shiva said the curse would stay but lessened the impact. He made Chandra wane to a new moon (death) and then wax back to life (full moon). This Skanda Purana story is about the Synodic month (when the moon returns to the same state of lustre) in approximately 30 days.
The Hindu luni-solar calendars follow this definition of a month. Each month is named after the star constellation in which the sun is observed during the advent of full moon. Karnataka, Maharashtra & Telugu states follow the amanta calendar marking a month from new moon to new moon. The 1st new moon day of the Chaitra month is the new year i.e Gudi Padwa & Ugadi. Northern states follow the purnimanta definition of a month (full moon to full moon). There the new year is on the 1st full moon day of Chaitra month – day after Holi.
Kerala, Tamil Nadu, Punjab & East follow solar calendar where the new year is on 1st day of Vaisakh month coinciding with Mesha Sankranti when Sun enters the Aries constellation (normally April 14th).
The picture is Shiva as Chandrasekhara capturing this story.

Markandeya Purana recounts how the wives left the Saptharishis and formed a constellation.
The Saptharishis conducted a Homa. During the Homa, Agni was besotted with their lovely wives. Agni’s companion Svaha seduced Agni by taking the form of these wives. People mistakenly complained that there was an illicit romance between Agni and the wives. The wives were shamed and embarrassed by this allegation. Six of the wives left the Saptarishis (Ursa Major/ Big Dipper, Great Bear constellation) and separately became the six sisters – Krittika (Pleiades constellation). The ancient Greeks too had a parallel but different story about the seven sisters.
Picture is Agni with Svaha, Wikimedia

Svaha could not impersonate Arundhati, Vashista’s wife, due to her purity. Therefore, Arundhati, remained with her husband forming the double star Mizar-Alcor in the Ursa Major constellation. She remains the epitome of virtue.
In traditional Indian wedding ceremonies, the pandit shows the newly-weds the Arundhati nakshatra in the sky. In most twin star systems, one star is stationary and the other revolves around it. Vasishtha & Arundhati rotate in synchrony – denoting mutual importance of both partners. Our ancients used an astronomical phenomenon to craft a beautiful lesson on marriage.
A wedding image of the couple watching Arundhati.

Vishnu Purana recounts the story of prince Dhruva. His father had ignored his mother, Queen Suniti, due to the influence of his other wife Suruchi. One day, Dhruva tried to sit on his father’s lap. But he was pushed aside by the stepmother who told him the he does not deserve the place. Dhruva was hurt by this. His mother told him to approach Vishnu. Dhruva did a penance to Vishnu seeking his place on the Earth. When Vishnu appeared before him and granted a boon, he just praised Bhagwan and said he was content. Vishnu made Dhruva an immobile star in the sky, and made all celestial bodies go in pradakshina of Dhruva.
Today, we have a relatively bright pole-star in the northern hemisphere called Polaris that we refer to as Dhruva. Long exposure photography shows the concentric paths that celestial bodies take around Polaris over several hours. Dhruva stays almost still, firmly in place as centre of rotation.
A Raja Ravi Varma painting of Dhruva and Vishnu.

Puranas tell us that the Vindhyas tried to compete with Himalayas in height. It started obstructing the sun. People invoked Agastya, Vindhyas’ guru. Agastya told Vindhyas that he was going south and he should stay prostrated till he returned. He never returned and therefore Vindhyas remained still and did not grow.
Some interpret this as the tale of Agastya going south to spread Vedic culture. He is traditionally credited with creating Tamil language.
Canopus, the 2nd brightest star is called Agastya in India. Due to the phenomenon of precession, it was not visible in India in ancient times. It is calculated that it became visible in Northern India only in 3000 BCE.
Source: KD Abhyankar, “Folklore & Astronomy: Agastya, A Sage and A Star”
Wikimedia image of Sage Agastiya

Swarbhanu is an asura mentioned in the earliest Rig Vedic books as being responsible for eclipses. In a popular Puranic story, he disguises himself as a deva and consumes Amrita (nectar) during samudra manthan. Surya & Chandra recognise him and point him out to Vishnu who cuts off his head. However, as he had already consumed amrita, the severed head became Rahu and the headless body became Ketu, both becoming immortal. To take revenge Rahu and Ketu periodically try to swallow the Sun and the Moon causing the solar and lunar eclipse.

Early Indian astronomy focused on the night sky & stars. Navgrahas (Nine planets) are a later addition and include Sun, Moon & five planets of the solar system—Mercury through Saturn, excluding Earth. Rahu and Ketu are two “dark” or “shadow” planets (tamograha or chayagraha) that complete the set. Astronomically, they denote the two points of intersection of the paths of Sun & Moon in the celestial sphere and are 180 degrees apart . The explanation that invisible planets cause eclipses is unique to India . Ketu in early Indian texts also refers to comets or meteors, bright flashes imagined as ill omens.

Navagrahas are believed to directly influence people’s lives and they have been worshipped in temples in human form since the 5th cent CE.

Source: https://www.britannica.com/topic/navagraha
Picture Credit: Bhagavatam Katha

Saturn takes 30 years to go around the sun, a slow moving planet. ‘Sanaischara’ means slow moving. Shani is slow but sure. One cannot fool him with offerings. He bestows grace based on one’s karma only.
Shani is the son of Surya & his junior wife Chaaya. Shani’s half siblings are Yama, Yami & Ashvins. Shani had strained relations with his family. In a fight, he injured his leg and became slow moving. But he propitiated Shiva and got the boon to be the most powerful in the navagrahas. Having suffered taunts as a child for his looks, he wanted to look beyond what is apparent and rewards people based only on their karma. Shani Sade Saati is the 7.5 year period in every person’s life that brings challenges. It is also a period of karmic cleansing.
Source: https://www.rudraastro.com/blogs/astrology/the-story-of-the-nine-planets-or-the-navgrahas
The picture is Shani Bhagwan deity, in open air, at Shani Shingnapur in Maharashtra

Jupiter’s revolution around the sun takes approximately 12 years. Kumbh mela is celebrated in four sacred sites (Haridwar, Ujjain, Nashik, Prayagraj) in a 12-year cycle. Each Kumbh Mela marks distinct set of astronomical positions of the Sun, the Moon, and Jupiter.
Jupiter is called Guru or Brhaspati, the teacher of the devas. Thus, it is associated with knowledge and gravity. Guru also means weight, the Sanskrit word for gravity is ‘gurutvakarshan’. The Sanskrit root ‘Brh’ represents big. Thus in astrology, Guru is large hearted and beneficent.
Source: https://www.britannica.com/topic/Kumbh-Mela

The planet Venus reaches its utmost brightness shortly before sunset or sunrise. Therefore it is called the Evening or Morning Star. It is associated with beauty. The Romans called it Venus, goddess of love & beauty. Because of its brightness, it is a celestial body that guides travellers.
Shukra is the master of wisdom. He is revered for his mastery of Mrita-Sanjeevani (bringing the dead to life) and teachings in Nitisara (statecraft). Shukra chose an unconventional path and sided with the Asuras inspite of his great scholarship. In the Vamana Avatar story, Sukhracharya recognises that Vishnu is coming in the form of Vamana and warns King Bali.
Sukracharya never shied away from pointing the right path to Asuras. Sukracharya always treated his opponents fairly. Puranas tell many stories of his duels with Brhaspati (Jupiter), guru of the devas and his pupils. Thus, as per astrology Shukra brings good relationships, beauty & abundance in life.
Source: Exotic India Art
Picture Credit: Odisha State Museum

Chapter 10, verse 35 of the Gita states, “māsānāṁ mārga-śhīrṣho aham ṛitūnāṁ kusumākaraḥ”

(Of the months I am Margsheersha, and of seasons I am spring, which brings forth flowers).

Margasheersha, Margazhi in Tamil and Agrahayana or Aghan or variations in other languages, falls in the late November – Mid January period. It is the ninth month in traditional calendars. It is perhaps considered auspicious because it is the main harvest month or because the Gita was delivered during the month. Some argue that when Krishna spoke the Gita, it was associated with spring season and not winter as he refers to margasheersha and spring together in the same line. The luni-solar calendar has slipped due to the earth’s precession and what was spring then, is now winter.

Source: https://www.holy-bhagavad-gita.org/chapter/10/verse/35/

The picture is the recital of sacred Thiruppavai (to Krishna primarily) in the Marghazhi month on the streets of Tirupati.