Just How Big Is The Universe?
We know that galaxies can be millions of light-years away, but these numbers tend to just go over our heads, so let’s find out just how big the Universe really is.
How many times have you heard that the Universe is staggeringly vast? Scientists still can’t decide whether it is infinite in size (though due to the speed of light’s universal speed limit, it doesn’t matter). Still, the part we can see, the ‘visible Universe’ is so expansive that we struggle to get our head around how many billions of light-years wide it is. So, let’s take the time to zoom out of our macro world, see the big picture and get a grip on how tiny we are compared to this seemingly endless stage upon which we enact our lives.
Let’s start with something we can understand, the Earth. It’s a sizeable soggy ball with some rather astounding creatures inhabiting its surface. All known life exists here apart from a few lucky apes who are currently whizzing around it in a space station called the ISS. This station isn’t as far away as you might think as it orbits at only 408 km from the surface of the planet.
Let’s look at some figures to put the size of the Earth into perspective. The Earth has a diameter of 12,742 km (7,917.5 mi) and a circumference of 40,075 km…
