The universe is a strange and wonderful place, primarily empty space with a smattering of galaxies scattered about. Each galaxy has hundreds of billions of stars and the universe itself is so vast that it has one hundred billion galaxies. The enormity and scale is impossible to get our heads around and it takes rare geniuses like Einstein, Newton and even Hawking who have the uncanny ability to visualise, scrutinise and probe the depths and workings of the universe. Even the nearest star to us is 4 light years away, which in layman’s terms is a staggering 40 trillion kilometers, that is 40 with 12 zeros after it. The Voyager 1 spacecraft, launched in 1977 to study the solar system travels at 62,000 km/h. At this speed, It would take 73,000 years to get to the nearest star and a cool 640 million years to get to the centre of our galaxy!
It gets even stranger, the universe is expanding, it’s getting bigger and bigger. Conversely last week it was smaller and even smaller still two weeks ago. Follow this logic through and we arrive at the big bang. A point in space and time when the universe burst into existence and filled the nothingness with matter and time. Since that point 13.8 billion years ago the universe has been rapidly expanding and continues to do so, driven apart by a mysterious force called dark energy.
Our Sun and solar system including Earth sparked into life 4.5 billion years ago, formed from clouds of gas and dust from previously burnt out stars. You and I, and the world around us is made from chemical elements forged in the nuclear furnace of these stars when they were alive, and from the heavier elements made when they blew themselves to bits billions of years ago.
And that is just the stuff we can see. The universe of normal matter and energy that we can observe, accounts for a mere 5 % of the total universe. Dark matter, stuff we can’t see directly or don’t know what it is exactly, makes up 25 % of the universe, with the aforementioned mysterious dark energy making up the remaining 70 %. In 1927, the biologist J.B.S. Haldane summed it up quiet nicely. “My own suspicion is that the universe is not only queerer than we suppose, but queerer than we can suppose”.