Linux

Warning: this is definitively doable, but messier than it looks like. I'd recommend you to partition it manually, before installing any distro, like this:

• one partition per distro. For sizes check their requirements. Given 500GB I'd probably reserve 60GB for each, perhaps a bit more if I know that I'll install a lot of stuff in that distro.
• one swap partition, that'll be accessed across distros. Optional if you have 16GB+ of RAM.
• use the leftover space for a "storage" partition, for personal files that you won't save in someone else's computer (i.e. the cloud). That allows you to mess with the distros without risking your personal files.

Don't worry too much on getting the space right though - if necessary you can always resize a few partitions after installation. It's a bit of a bother though.

Do not share /home across distros, it's simply more trouble than it's worth. Instead, mount that "storage" partition in each distro, inside your /home/[$username] directory.

Another thing that you might want to consider is virtualisation. Odds are that you won't use a lot of those distros in your everyday, and that you're just curious about their differences. In that case, consider installing one of them, install Virtualbox in it, and then the other distros get installed inside Virtualbox. I'm suggesting that because it'll use overall less space, and make distro management less messy.