Maarg Manthan · Topic 10.3

Astronomy (Aryabhatiya, Varahamihira, Observatories)

Art & Culture › Science & Technology in Ancient India · Topic 10.3

Ancient Indian astronomy, called Jyotisha, grew from the Vedic need to fix the calendar and ritual dates. The Vedanga Jyotisha is its oldest surviving text. Aryabhata, in the Aryabhatiya of 499 CE, held that the Earth rotates on its axis and explained eclipses by shadows. Varahamihira summarised five older schools in the Pancha Siddhantika, Brahmagupta wrote the Brahmasphutasiddhanta in 628 CE, and Bhaskara II wrote the Siddhanta Shiromani. In the 18th century Sawai Jai Singh II built five Jantar Mantar observatories, at Delhi, Jaipur, Ujjain, Varanasi and Mathura, of which Jaipur is a World Heritage Site.

5 min read · UPSC Prelims · Art & Culture · Science & Technology in Ancient India

At a Glance

Oldest text Vedanga Jyotisha
Aryabhata Aryabhatiya, 499 CE; rotating Earth
Varahamihira Pancha Siddhantika, Brihat Samhita
Observatories Jantar Mantar, Sawai Jai Singh II
World Heritage Jantar Mantar, Jaipur (2010)
Exam link UPSC Prelims, Art and Culture: Science & Technology in Ancient India

Where Does It Fit?

This topic follows mathematics in the macro on science in ancient India. Almost every astronomer listed here was also a mathematician, and their calculations served the calendar, the almanac and temple rituals. Previous topic: Mathematics (Zero, Decimal System, Aryabhata, Brahmagupta). Next topic: Medicine (Ayurveda – Charaka, Sushruta).

Which Astronomers and Texts Matter Most?

Astronomer or text	Period	Key contribution
Vedanga Jyotisha	Late Vedic period	Oldest text of the Jyotisha Vedanga, a calendar for fixing ritual times, linked to Lagadha
Surya Siddhanta	Early centuries CE, revised later	Standard Sanskrit work on planetary motion, with sine tables and a method of finding eclipses
Aryabhata	499 CE	Aryabhatiya, Earth rotates on its axis, eclipses caused by shadows of the Earth and Moon
Varahamihira	6th century CE, Ujjain	Pancha Siddhantika (five older siddhantas), Brihat Samhita, Brihat Jataka
Brahmagupta	628 CE	Brahmasphutasiddhanta and Khandakhadyaka, worked on planetary positions and eclipses
Lalla	8th century	Shishyadhividdhida, a work that followed and revised Aryabhata
Bhaskara II	12th century	Siddhanta Shiromani with sections on planets and the sphere, daily motion of planets
Mahendra Suri	14th century	Yantraraja, the first Sanskrit work on the astrolabe, written under Firuz Shah Tughlaq
Nilakantha Somayaji	15th to 16th century, Kerala	Tantrasamgraha, a planetary model close to later European ideas

What Are the Jantar Mantar Observatories?

Builder: Sawai Jai Singh II (1688 to 1743), the Kachwaha ruler of Amber, who founded Jaipur in 1727
Five sites: Delhi (1724), Jaipur (1728 to 1734), Ujjain, Varanasi and Mathura, and the Mathura observatory no longer survives
Largest: the Jaipur Jantar Mantar is the largest and best preserved
Samrat Yantra: a giant equinoctial sundial at Jaipur, about 27 metres high, which tells time to within seconds
Other instruments: Jai Prakash Yantra, Ram Yantra, Rashivalaya Yantra, Chakra Yantra and Narivalaya Yantra
World Heritage: the Jantar Mantar, Jaipur was inscribed in 2010, as an example of an astronomical observatory of the Mughal-era court
Material: built of stone and lime plaster, with brass fittings in some instruments
Purpose: to prepare accurate astronomical tables, the Zij-i-Muhammad Shahi, named after the Mughal emperor Muhammad Shah
Ujjain link: Ujjain was the old prime meridian of Indian astronomy, and its observatory is still active as a government-run site

What Else Should You Remember?

Jyotisha branches: Siddhanta (mathematical astronomy), Samhita (omens and weather), and Hora (horoscopes)
Nakshatras: 27 lunar mansions are mentioned early in Vedic texts and form the base of the Hindu calendar
Panchanga: the Hindu almanac gives tithi, vara, nakshatra, yoga and karana
Aryabhata on the Earth: he said the apparent westward motion of stars is due to the rotation of the Earth, which was a bold claim for the age
Heliocentric ideas: Aryabhata is sometimes said to have used a sun-centred scheme for inner planets, but scholars debate this, so it is safe to say only that he accepted Earth rotation
Varahamihira’s range: the Brihat Samhita also treats architecture, water divining, gems, omens and plant science
Ujjain as centre: Ujjain was a leading school of astronomy in Gupta and post-Gupta times, with Varahamihira and Brahmagupta linked to it
Kerala school: the Kerala astronomers kept careful observations until the 16th century and refined planetary theory
Modern institutions: the Aryabhatta Research Institute of Observational Sciences (ARIES) at Nainital and the Indian Institute of Astrophysics at Bengaluru continue the tradition in modern form
Space age link: Aryabhata was India’s first satellite, launched in 1975
Note on Konark: the wheels of the Konark Sun Temple in Odisha work as sundials, and this fits the sun cult but is a monument fact, not an observatory

Why Does It Matter for the Exam?

Author and text: matching Varahamihira, Aryabhata and Brahmagupta with their works
Observatories: Jantar Mantar sites, builder and the UNESCO year (2010)
Concepts: Earth rotation by Aryabhata and the Pancha Siddhantika summary
Statements: a common trap is giving the observatories to Akbar or Shah Jahan
Mains: topics on India’s scientific heritage can use astronomy with the mathematicians in Mathematics (Zero, Decimal System, Aryabhata, Brahmagupta)

As an analytical point, Indian astronomy served religion and the calendar, yet it kept a spirit of observation and calculation. Revival of public interest in observatories can link heritage tourism with science education.

Why Is This Topic Important?

Authors Text and author pairs
Sites Jantar Mantar facts
Concepts Earth rotation

What Came Next?

The next topic turns from the sky to the body, covering Ayurveda, Charaka and Sushruta. Next topic: Medicine (Ayurveda – Charaka, Sushruta).

Key People and Terms

Jyotisha Astronomy and astrology
Siddhanta Mathematical astronomy treatise
Panchanga Hindu almanac
Yantra Instrument
Nakshatra Lunar mansion
Zij Table of star positions

Study this topic together with these linked topics from other subjects.

Science and Technology in the Gupta Age (Ancient History)

Exam Corner

Points to Remember

Earth rotation: Aryabhata.
Pancha Siddhantika: Varahamihira.
Jantar Mantar: Sawai Jai Singh II, five sites.
Jaipur site: UNESCO 2010.
Oldest text: Vedanga Jyotisha.

Do Not Confuse With

Jantar Mantar sites Delhi, Jaipur, Ujjain, Varanasi, Mathura
Brihat Samhita and Brihat Jataka Encyclopaedia of omens versus a horoscope text
Siddhanta and Samhita Calculation versus omens and weather

Memory Hook

Aryabhata spins the Earth, Varahamihira sums five schools, Jai Singh builds in stone.

Mains Angle

Questions ask how ancient science can be preserved and presented. These points give a frame.

Science heritage Calendar, eclipses, observation
Conservation Jantar Mantar upkeep and tourism
Education Public science at heritage sites

A Question You May Face

An original practice question, not a past paper question.

“Discuss the contribution of ancient Indian astronomers and the significance of the Jantar Mantar observatories as scientific heritage.”

How to Answer

Texts Siddhantas and almanac.
People Aryabhata, Varahamihira, Brahmagupta.
Sites Jantar Mantar five.
Way Conserve and teach.

GS Relevance

Prelims: astronomers and texts, Jantar Mantar, Vedanga Jyotisha, Surya Siddhanta. GS Paper 1: Indian heritage and culture, contribution of ancient India to science.

Frequently Asked Questions

Who built the Jantar Mantar observatories?

Sawai Jai Singh II, the Kachwaha ruler of Amber who founded Jaipur, built five observatories in the first half of the 18th century. They stand at Delhi, Jaipur, Ujjain, Varanasi and Mathura, and the Mathura observatory has not survived. The Jaipur site is the largest and best preserved.

When was the Jantar Mantar at Jaipur made a World Heritage Site?

UNESCO inscribed the Jantar Mantar, Jaipur on the World Heritage List in 2010. It was cited as an outstanding example of an astronomical observatory with stone instruments, built under Sawai Jai Singh II between 1728 and 1734, and it contains the Samrat Yantra.

What did Aryabhata say about the Earth?

Aryabhata, in the Aryabhatiya of 499 CE, stated that the Earth rotates on its axis and that the apparent movement of the stars is due to this rotation. He also explained eclipses as the shadow of the Earth and the Moon, not the work of demons.

What is the Pancha Siddhantika?

The Pancha Siddhantika is a work of Varahamihira, written in the 6th century CE, that summarises five earlier astronomical schools, called the Paulisa, Romaka, Vasistha, Surya and Paitamaha siddhantas. It is valuable because several of the original works are lost.

What is the Vedanga Jyotisha?

The Vedanga Jyotisha is the oldest surviving text of Jyotisha, one of the six Vedangas, and is linked with Lagadha. It gives a calendar based on the Sun and Moon, used to fix the right days for Vedic sacrifices, and sets the base for the later Indian almanac.

PYQ Practice — Statement Analysis

1 Sawai Jai Singh II built five observatories called Jantar Mantar.

True

At Delhi, Jaipur, Ujjain, Varanasi and Mathura.

2 The Pancha Siddhantika was written by Aryabhata.

False

It is the work of Varahamihira.

3 The Jantar Mantar at Jaipur was inscribed by UNESCO in 2010.