Given that the moon-earth distance varies, these planets would, twice a month at around the half moon, fit in <i>exactly</i> with no space left over<p>It varies between 360000km and 405000km ish
<a href="https://en.wikipedia.org/wiki/Lunar_distance" rel="nofollow">https://en.wikipedia.org/wiki/Lunar_distance</a>
I'm pretty sure I've seen an infographic of this maybe a decade or more ago, but it was also a fact on No Such Thing As A Fish (the QI elves podcast) recently. I wonder if the Reddit poster picked it up from them.<p><a href="https://pscrb.fm/rss/p/pdst.fm/e/arttrk.com/p/ABMA5/dts.podtrac.com/redirect.mp3/audioboom.com/posts/8428369.mp3?modified=1704994321&sid=2399216&source=rss" rel="nofollow">https://pscrb.fm/rss/p/pdst.fm/e/arttrk.com/p/ABMA5/dts.podt...</a> - "513: No Such Thing As Upside-Down Space Rain", 4m36<p>Shout out to AntennaPod, installed from F-Droid app store; far-and-away the best podcast listening app I've found.
This is not quite what it seems.<p>What happens as you pile mass into a planet is that the planet becomes <i>dense</i>, not <i>large</i>, and this is because of gravity.<p>Jupiter has more than twice the mass of Saturn, but is only moderately larger in diameter.<p>You can keep dumping mass into a planet, and it just won't get much bigger, until you have <i>enough</i> mass that fusion kicks off, and then suddenly the now-a-star inflates, because it becomes extremely hot and then you have something the size of the Sun.
This is one of those things that seems incredible at first, but when you think about it, isn't actually that strange at all: Yes, some of these planets are massive, but the problem has always been (in observing or visiting them) their vast distance from Earth, not their actual sizes.