Ask Ethan: What if the Sun were a grain of sand?

From the perspective of a human being, it’s almost impossible to fathom just how mind-bogglingly large the cosmic scales are. An average human is a little less than 2 meters in height, but planet Earth is more than 12,000 kilometers in diameter. The Sun is larger, at 1.4 million kilometers across, and incredibly far away: some 150 million kilometers distant. And these numbers, grand though they may seem, are paltry compared to what lies beyond our inner Solar System. Neptune is more than 4 billion kilometers away; the next-nearest star, Proxima Centauri, is 4.2 light-years (or ~40 trillion km) distant, while the Milky Way itself is more than 100,000 light-years across. All of that doesn’t even take us beyond our own galaxy, to the trillions of others stretched across the observable Universe. Yes, it’s incredibly hard to fathom, but what if we shrunk those scales down to something more familiar? That’s the idea of <a href="https://www.patreon.com/startswithabang" rel="noopener ugc nofollow" target="_blank">Patreon supporter</a> Pete Smoyer, who wants to know: <a href="https://medium.com/starts-with-a-bang/ask-ethan-what-if-the-sun-were-a-grain-of-sand-d0b041c9c734">Learn More</a>