The first thing that jumped to my mind when I read that No Man's Sky would have 18 quintillion planets is that I would need to make space on my already packed hard drive. Fortunately — and almost miraculously — it turns out the game will not take up much space at all.
In fact, the entirety of No Man's Sky is only 6 GB on a PlayStation 4 disc and 10 GB to download from Steam.
This is incredibly small compared to other games.
When you look at modern games — especially on PC — it often seems assumed that the game will take up a sizable chunk of space. Grand Theft Auto V requires at least 65 GB of space to download off Steam, while and expansive MMO like World of Warcraft is nearing 50 GB of space.
Even a small indie game like Stardew Valley takes up at least 500 MB of space. Which, yes, is quite a bit less than the 10 GB a PC will need for No Man's Sky but comparatively, No Man's Sky has practically endless content.
This probably seems like an impossibility when compared to other games — heck, I'm still wrapping my mind around it all — but it can actually be explained relatively simply.
The small size is thanks to the way the game generates planets.
As we've discussed before, the game has a special way of generating planets for players to keep it from having any load times. This means that the only code the game needs to store is the code that tells the computer how exactly to generate content on the fly. In his tweet, Sean Murray revealed that this means most of the space requirements are actually due to audio!
The rest of the space not dedicated to audio or the planet-generating code is likely taken up by static assets such as your ship, your gun, or the upgrades you can apply to them.
The best news? The team is already working on the next No Man's Sky update.
In a follow-up tweet, Sean Murray mentioned that Update 1 is already in the works. There was no mention of what would be included in the update, but depending on the content, it's hard to imagine any updates for the game would take up very much space.
However, with the number of planets set and limited by the 64-bit system, it seems unlikely that updates would make changes to planets. More than likely, updates would include different ways to customize your ship, gun, or other ways to help you explore and survive on other planets.