Dark matter is entirely invisible, emitting no light or energy, making it undetectable by conventional sensors and detectors.

dark matter, a component of the universe whose presence is discerned from its gravitational attraction rather than its luminosity. Dark matter makes up 30.1 percent of the matter-energy composition of the universe; the rest is dark energy (69.4 percent) and “ordinary” visible matter (0.5 percent).

The Universe is all of space including everything that exists. Our planet, all other planets in existence, stars, and galaxies are all part of the universe. It was born more than thirteen billion years ago in the Big Bang. Scientists say that it is at least ten billion light-years in diameter. In this sense, the Universe means the Cosmos. The Universe is all time and space, i.e., spacetime. It includes all the galaxies, stars, planets, moons, and all other forms of energy and matter.

Science is the intellectual and practical activity encompassing the systematic study of the structure and behaviour of the physical and natural world through observation and experiment.