Time to think big!
Just how big, is big? An elephant? A blue whale? A skyscraper? The moon? The burden of guilt you’ve carried since grade 3 when you lied to your teacher about stealing a packet of Sakatas but your classmate Steven took the fall and ended up with a 15 minute detention? Well, I can definitely tell you, we can go a lot bigger (maybe not bigger than that last one though… Steven if you’re reading this, I never meant for you to get caught up in it all, Ms Clancy was a damn scary teacher). So buckle up and get ready to take a tour through the massive objects we can find in our universe.
Star-ting small (but really, quite big)
To start our journey into the world of big, lets first take a look at our very own star, the Sun. Weighing in at 330,000 times the weight of the Earth (1.989 x 10^30 kg), this bad boy accounts for 99.8% of the mass of the entire solar system! Diameter wise, though, only 109 of Earth could fit along the face of the Sun (1.4 million km), and volume wise it only takes up a smidgen of all the space in the solar system. We could go on about the Sun all day, but I’m sure there are some of you reading who might get fed up pretty quickly… so time to move on to other stars!
If you thought the Sun was big, get ready for a big surprise. As far as stars go, the one we orbit really ain’t that much to talk about. To kick things up a gear, we can start with Aldebaran. This red-orange giant star, located around 65 light years away from us, is 150 times brighter than our Sun, and is as wide as 52 Suns lined up! That’s 5668 Earths! We are only on the second item in our ‘list of big’ and we’ve reached sizes that are pretty hard to comprehend.
Next up is the first of the super-giants, Rigel. It is about 85,000 times brighter than the Sun, and has a width 70 times larger than the sun. But stars can get so much bigger! So let’s quit beating around the bush and move on to the biggest: VY Canis Majoris. This baby has a diameter of 2.7 billion km. This means that lined up side to side, you could fit 2000 of our sun in that space. Volume wise, you could fit 9.3 billion of our Sun in there. What’s more, is Canis Majoris is expected to explode in around 100,000 years in a supernova! Fortunately, this star is around 4,900 light years away from Earth, so if anyone is around when this guy blows, all they might see is an extra bight twinkle in the night sky.
Scaling up to galactic proportions
The next big step up is onto galaxies, massive systems comprised of millions or billions of stars, dust, and gas, held together by the force of gravity. The Milky Way, our own galaxy, is believed to contain upwards of 150 billion stars. How big is it then? 100,000 light years! Sizes like this are when you really have to stretch your imagination to think about how big they really are. If you were to drive at 110 km/h, it would take 1 trillion years to cross the diameter of the Milky Way. Unfortunately there won’t be many service stations in space, so refuelling and pee breaks might be stretched thin!
However, galaxies themselves can cluster into groups, also held together by gravity. Moving onto these galactic clusters, we are finally approaching the biggest structures in the universe. The Milky Way itself is a part of the small ‘Local Group’ that is comprised of around a couple dozen galaxies. Included in this cluster is our closest neighbouring galaxy, the Andromeda galaxy (Fun fact: in around 4 billion years, the Milky Way and Andromeda will actually collide!).
Finally, to top it all off, galactic clusters can also cluster! These incomprehensible structures are not so imaginatively called superclusters. The biggest of them all, the biggest known structure in the observable universe, is called the Great GRB Wall, and is 10 billion light years across. As a matter of fact, this has confounded astronomers, as theory suggests structures this size shouldn’t be able to exist!
We’ve now reached the end of the list, and ticked off the biggest structure within our universe. So hopefully this can provide you with some insight to the guilt I have felt towards the Steven Sakata Saga.
Tune in next week, when we discuss the smallest things in the universe, such as atoms, electrons, the Planck distance, or the amount of will I have left stopping me from dropping out of uni and taking up a career as a demotivational speaker.
PS. If visual comparisons are more your thing here’s a great (albeit, a bit long) video showcasing the true scale of the things I mentioned in this post: