Yajnavalkya's theory of heliocentrism

Yajnavalkya's theory of heliocentrism is the heliocentric model of the Solar System mentioned in the Vedic text Shatapatha Brahmana. It was proposed by the Indian philosopher Yajnavalkya.

Background
Yajnavalkya proposed a heliocentric model of the Solar System between 9th-7th Century BCE stating that the Sun was "the center of the spheres". The theory proposed is also known as Yajnavalkya Heliocentrism.

According to his concept the Solar system, the Earth is spherical and the Sun is at the center of the spheres. It is mentioned in his work Shatapatha Brahmana as

"The sun strings these worlds – the earth, the planets, the atmosphere – to himself on a thread.”" He recognised that the Sun is much larger than the Earth. He also invented the method of measuring the relative distances of the Moon and the sun from the Earth. He used mathematics and geometry in some religious rituals in the Vedic Tradition. According to some scholars that, he measured the relative distance of the Sun and the Moon from the Earth to an accuracy of 108 times the respective diameters of these celestial bodies, which was close to the modern measurements of 107.6 for the Sun and 110.6 for the Moon.

Sun's Orbit
In Yajurveda, Yajnavalkya had also mentioned about the motion of the Sun. According to Yajurveda 33.44, "“The sun moves in its own orbit in space taking along with itself the mortal bodies like earth through force of attraction.'"According to the verse, the sun has its own orbit, that means the sun is revolving around a centre. This centre is the centre of masses in Solar system. The verse also introduced the concept of the attractive force between the sun and the earth, which is also the concept of the gravitational force in Yajnavalkya's work.