People can fall: â  from the edge of a completed roof; â  from the edge where work is being carried out; or â  through openings or gaps. Edge protection Unless the roof parapet provides equivalent safety, temporary edge protection will be required during most work on flat roofs.
Why is astronomy considered the original science? Astronomy is the oldest science for our ancients either drew or made structures according to seasons or movements of celestial bodies in our Universe.
Definition of astronomy: Astronomy is the study of the sun, moon, stars, planets, comets, gas, galaxies, gas, dust and other non-Earthly bodies and phenomena.uccinctly put, astrophysics involves the study of the physics of astronomy and concentrates on the behavior, properties, and motion of objects out there. However, modern astronomy includes many elements of the motions and characteristics of these bodies, and the two terms are often used interchangeably today.