purvam bhumim pariksheta paschaat vaastu prakalpayet ||

first test the earth (site); after that plan construction.

valmikena samayukta bhumirasthiganostu ya ||
randranvitha cha bhurvarjya gatighescha samanvita ||

land with ant hills, skeletons, full of pits and craters should be avoided

varnagandharasakaradishabdasparsanairapi|
parikshyaiva thathayogyam gruhniyaad dravyamuttamam ||

after examining the colour, smell, taste, shape, sound and touch (of the soil) buy the best material as found suitable,.

yavattatra jalam drushtam khanettavattu bhutale |

Till water is seen there (one) should dig the ground.

Ratnimaatramadhe garte parikshya khatapurane ||
aadhike sriyamapnoti nyune haanim same samam ||

it,(soil) should be tested by digging a pit of 1 arm length and refilling it (with the same soil). if (soil) is more, one wil beget prosperity; if short, one wil beget loss; if equal, it is normal.



source : matsya puranam, Adhyayah 253, slokah 11.(puranic period)
vastu puranam, slokah 5, viswakarma (6th century AD).
Bhrugu samhita, Adhyayah 4 (post vedic period)
kasyapa silpah, adhayah 4, (post vedic period)

Trinaabhichakramajaramanarvam yatrema
viswa bhuvaanani tasthuhuh |

the elliptical path through which all the celestial bodies move, is imperishable and unslackened.

source: rigveda samhita, mandalam 1, suktam 164, mantrah 2 (6000 BCE)

planetary motion

kakasha prathimandalaga bhramanthi sarve grahah swacharena |
mandochhadanulomam prathilomanchaiva shegrochhat ||

the mean planets move on their orbits and true planets on their eccentric circles. All the planets whether moving on their orbits or on the eccentric circles move with their own motion, anticlockwise from their apogees and clockwise from their perigees.

source: Arybhatiyam, Kalakriya-padah, chapter 3, slokah 17, aryabhatah (b.499)

orbiting planets- Concept of gravity

akristisaktisca mahi taya yat
khastam guru swabhimukham swasaktya |
aakrushyate tatpatativa bhaati
same samantaat kva patatviyam khe ||

the attracting (gravitational) force is the earth. that earth with that gravitational force of hers attracts towards herself the large objects in the sky. it seems as though she is falling. in space, with matching forces where wil she fall

source: siddantha siromanih, Bhuvanakosah 6, bhaskara 2.

Moon - A Satellite of the Earth

आयंगौ: प्रुस्निराक्रमिदसदंमातारम पुरः |

पितारँच प्रयांत्स्वः ||

Aayangauh prusnirakramidasadanmaataram purah |

pitarancha prayantsvah ||

"The moon, being a satellite of the earth, revolves a round its mother planet and follows in it its revolution round the self-luminous father planet (the sun). "

Source: Rig-Veda, Mandalah 10, suktam 189, Mantrah 1 (6000 BCE)

Astronomy - Lunar Eclipse

छादायती शशि सूर्यं शशिनं महती च भुछाया 

chadayati sashi suryam sasinam mahati cha bhuchhaya


"The moon covers the sun and the great shadow of the earth covers the moon"


Source: Aryabhattiyam, Golapadah, chapter 4, slokah 37 (b.499 A.D)

Astronomy - The Speed of light

तरनीर्वदार्स्हतो  ज्योतिस्क्रुदासी सुर्य  |

विस्वम्भासी रोचनम  ||

Tarnanirvisvadarsato jyotiskrudashi surya  |

visvambhasi rochanam ||

"Oh Sun! (You) overwhelm all in speed, visible to all, source of light. (You) shine pervading the Universe."

tatha cha smaryat 

yojanaanam sahasram dve dve shate dve cha 

yojane | ekena nimishaardhan kramamana namostute ||

तथा च स्मर्यत 

योजनानं सहस्रं ध्वे ध्वे  शते ध्वे च  

योजने | एकेन निमिषार्धन क्रममाना नमोस्तुते   ||

"It is remembered (that) salutations to Thee (sun), the traveller of 2,202 yojanas in half a nimisha"

Source: Rig-Veda-Samhita, Mandalam 1, suktam 50, Mantrah 4 (6000 BCE)