Ask ARSE: How Big is the Universe?

Another young Astro enthusiast has dropped us a line so let's go ahead and: Ask ARSE.

"Hi ARSE, my dad said that the universe is bigger than the Solar System and the galaxy we are in. Is this true? How big is the universe?"
Thank you,
Greg, 47."

Thank you for the interesting question George!

To put it in no uncertain terms, the universe has no centre, no edge and is rapidly expanding ever since the "Big Bang" some 13.8 billion years ago. So to quantify just how "large the universe is" has proven quite difficult. 

The big bang infogrpahic

To rationalise it so that a layman such as yourself can comprehend: if light takes 4 years to travel to earth from a neighbouring star, we consider this 4 lightyears away.

Light travels at around 299,792 kilometres per second and the universe is ever expanding. So for light to travel from the stars you see in the sky to earth to be observed, it must have travelled 13.8 billion light years to your eye.

The speed of light

Also, if you had a car that could travel at the speed of light, you would die of dehydration and hunger before you could reach any significant space structure, permitting the car was suitable to withstand the crushing pressure of zero atmosphere. 

We hope this has shed some light on your query and keep looking to the skies in wonder.

Remember to like and share on your social media platforms.

#Space_Aus