Cosmology is a grand science; it takes our imagination into the vast depths of the Universe. The Universe is so big that we cannot, in principle, see the whole of it. The universe, observable to earth-dwellers, is only 46.5 billion lightyears in every direction from our Earth, where each lightyear is a length of 9.46 trillion km.

The awe is stretched to its limit when we come to know of galaxies that are huge bunches of maybe a thousand or a 100 million or even a hundred trillion stars. The stars in each of these galaxies, though millions of miles apart, co-travel as if fastened with perpetual glue. These stars altogether hover around the centres of their galaxies, which are commonly homed by supermassive blackholes.

The universe doesn't have these galaxies in the hundreds or thousands, rather cosmologists estimate them to be 200 billion to 2 trillion, in the observable universe alone. These galaxies, again, travel together forming humongous galaxy 'filaments', many of whom, when put together, make galactic walls and sheets. These walls and filaments make the universe look like a three-dimensional woven mesh of long threads dangling in space-time. If one, someone like God, could look from outside, He would say, 'And the heavens made of woven strips, firmly tied together', Ad-Dhariaat (6).

Then, the Universe is also not static; it is constantly changing, moving and expanding. Stars and galaxies are moving away from each other at high speeds. In fact, the expansion rate accelerates by 73km/sec after every megaparsec (3.26 million........

© The Express Tribune