DARK MATTER (YET TO BE UNSOLVED)
Dark Matter is the hypothetical substance but cannot be detecting by telescope. Its presence can only be detected from its gravitational effect. It covers 27 % matter of our universe. It can hold the galaxies which can quickly apart from each other; the reason is these galaxies which are rotating too fast, even gravity cannot hold these galaxies. But these exists certain type of energy which holds all these galaxies together like a (functioning of glue). (NOTE): Dark matter is estimated to contribute 84.54% of total energy of our universe. From the concept of dark matter we conclude that this matter is dark means it is invisible matter. (REMEMBER): The Hubble Space Telescope shows a ring of dark matter in the galaxy cluster CL0024+17. The fact is that if we add all the stars, planets, gas clouds and other celestial objects, the galaxies still fall short in the gravitational field. Dark matter was first postulated by Jan Oort in 1932, there was insufficient evidence, to repre