GENERAL KNOWLEDGE

Detailed explanation-1: -The physical universe is defined as all of space and time (collectively referred to as spacetime) and their contents. Such contents comprise all of energy in its various forms, including electromagnetic radiation and matter, and therefore planets, moons, stars, galaxies, and the contents of intergalactic space.

Detailed explanation-2: -Over 80% of all matter in the universe is made up of material scientists have never seen. It’s called dark matter and we only assume it exists because without it, the behaviour of stars, planets and galaxies simply wouldn’t make sense. Here is what we know about it, or rather, what we think we know.

Detailed explanation-3: -There are basically three possible shapes to the Universe; a flat Universe (Euclidean or zero curvature), a spherical or closed Universe (positive curvature) or a hyperbolic or open Universe (negative curvature).