Noctis（取自拉丁语 “夜”之意）是一个开源的太空模拟游戏。此游戏最引人注目的特点与其小巧的体积（小于1MB）相比，它可以构造出一个完全虚拟的星系，让玩家在其中畅游。

游戏的科幻背景是这样的，很久以前，住在Balastrackonastreya太阳系中的Felysia星球上的一群智能猫科动物Felysian创造了宇宙飞船Stardrifter，用于星际探险。但后来，由于未知原因，它们逃离了自己的家园而不知所踪。一批Stardrifter被留在了星系中，但是无法与它们的族群取得联系。Felysian是Noctis星系中唯一的智能生命，所以没有其他文明可以寻找。

Noctis (Latin for "of night") is a computer space flight simulator featuring first-person visual exploration of an imaginary galaxy.

The player is manifested in Noctis as the pilot of spacecraft called a Stardrifter, capable of instantaneous interstellar travel. This allows travelling between stars, refuelling the Stardrifter from Lithium ion-ejecting stars, approaching planets in star systems and their moons, and even landing where it is physically possible. Many planets feature atmospheres and weather effects. Some harbour plants and animals, or even mysterious ruins. No goal or measure of success is imposed by the game: it simply allows to catalogue and annotate the player's discoveries in a common database of stellar bodies called the GUIDE, which is to be synchronised over the author's Internet server.