The full version of Weird Worlds: Return to infinite space is available on GOG.COM. You can purchase it here

Weird Worlds: Return to Infinite Space is a hybrid "roguelike" game of space exploration and starship combat set within a peculiar, as-yet-unvisited region of the galaxy known as the Purple Void. Each time it is played, a new and different "sector prime" and its vast frontier are randomly generated. Locations of stars and nebulae, homeworlds of alien races, distribution of lifeforms and artifacts, plot-twisting quest events--the whole game is remixed.

Note that unlike common roguelikes that last dozens of hours, Weird Worlds: Return to Infinite Space plays to its conclusion in less than thirty minutes - it's the perfect lunch break game! Features also include a fully animated star map, a unique turn-based movement system, real-time starship battles (at naval battle speeds, not "Super-Melee"), award-winning music and sound, and a robust battle simulator. Weird Worlds also has built-in support for community-created mods that can change anything and everything in the game!

Windows 10 users: If you're experiencing mouse issues, right click the launch icon or shortcut and set compatibility mode to Windows 8.

A couple of words from the game creator:
Want to know more about Weird Worlds? There's quite a lot despite the apparent small size of the game: mini-plots, back stories, oddball references galore, subtle and hidden clues, rare events, interesting things to do, what to use the weirder artifacts for, Easter eggs, exploits, outright spoilers (be warned) and much, much more. Go see! It's a blast to read.
https://tvtropes.org/pmwiki/pmwiki.php/VideoGame/StrangeAdventuresInInfiniteSpace

Btw, have you noticed? The universe is expanding! Want proof? Be sure to download the Weird Worlds"fan favorites" mod pack HEREE. From weapon mods to full conversions (!), the mod pack makes Infinite Space even more infinite!
http://www.infinitespacegames.com/weirdworlds/weird-worlds-mods

Also note: the very first game in Digital Eel's Infinite Space series, Strange Adventures in Infinite Space, is always available HERE free and DRM-free from itch.io.
https://rich.itch.io/strangeadventures

Speaking of Strange Adentures, programmers can get the original source code (2002) HERE and the new codebase (2021) for iOS, Linux and Widows HERE (zip) and here (tar.gz), They're both in the public domain..
Original source code: http://digital-eel.com/sais/source.htm
New codebase:
zip: https://github.com/kuroneko/sais/archive/v1.6.2.zip
tar.gz: https://github.com/kuroneko/sais/archive/v1.6.2.tar.gz

Lastly, if you're a phone gamer, and who isn't, you should check out Weird Worlds for android and iOS devices. Our Mac guys, Hen3ry and Chris, spent a LOT of time to make sure it plays just as well on phones as it does on microcomputers. Anyhow, you can grab Weird Worlds on Google Play HERE and on the App Store (iPad and iPhone) HERE.
Android: https://play.google.com/store/apps/details?id=games.nekoattack.weirdworlds
iOS: https://apps.apple.com/us/app/weird-worlds/id1545626379#?platform=ipad

Weird Worlds: Return to Infinite Space Demo screenshots