Humans are very arrogant creatures, and we often forget just how small we are in relation to the rest of the Universe. So much so that our units of measurement are very impractical to use on a larger scale, so we will mostly be using light seconds, minutes, hours, day, months and years to talk about the size of the Universe. Light travels at a speed of about 299,792 km/s, which means that light can travel around the Earth’s equator (40,030 km) almost 7.5 times in 1 second. That’s pretty fast, especially when you consider that a flight from Columbus, OH to Nashville, TN takes about an hour. With this concept of light speed in mind, consider the fact that it would take light 4 hours to reach Neptune and 1.87 years to reach the edges of the solar system. Remember, this is the same speed as the one that could circle Earth 7.5times in a single second. To keep going, the closest star to our own, Proxima Centauri, is 4.22 light years away! At its current rate, it would take Voyager-1 (the fastest man-made object) 73,000 years to reach this star!!
To zoom out even more, you would find that our galaxy is 1,000,000,000,000,000,000 km in diameter (which is 100,000 light years). So yeah, our galaxy is pretty big. Now take that galaxy and shrink it down even more as it starts to become indistinguishable among the other galaxies until you are at roughly 13.8 billion light-years from our Sun. This is the edge of the observable universe, not to be confused with the actual size of the universe. We call it this because the universe is only 13.8 billion years old, so the light from beyond that edge does not exist yet (from Earth’s prospective) To put it simply, as we look further into space, we also look further back in time so we cannot look further back than the start of the Universe. NASA scientists estimate the actual size of the universe to be 93.6 billion light years away.
So, the next time you forget just how small we all are relative to the size of the universe, take a quick look at the video below from Youtube:
Interplanet Ira 
TA comment: Good job on describing some of the overall distances of the universe. I find that the concept of scale always hits me the hardest when looking at actual numbers like these. I got excited to see that my car has been driven the equivalent of around the Earth a few times now, but it’s still nothing compared to the distance that light travels in one second.
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