Systems Tool Kit Alternatives

Space Engine is a realistic virtual Universe you can explore on your computer.

Stellarium is a free open source planetarium for your computer.

Open Source

FlexiQuiz is a powerful online test generator that enables you to create engaging online quizzes, tests, or exams in minutes. Choose from 100's of features to create a customized quiz that meets your objectives for business, education, or fun.

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Universe Sandbox ² is a physics-based space simulator where you can simulate Events and even break physics and friction with certain features.

Cosmonium is a 3D astronomy and space exploration program.

Orbiter is a realistic 3D real-time space flight simulator program. Official site with free download. DownloadDownload mirror 1 Europe - Textures - Gallery - Links - .

This is an app that will let you explore the Solar System!

Player Made Creations. Download the free Creature Creator to start making your own unique creations. See More · Spore. rabbi airs. Kangster.

3D model of the Solar System and night sky in real time

Build spacecraft, fly them, and try to help the Kerbals to fulfill their ultimate mission of conquering space.

Space Simulator is a Flight Simulation, Physics, Adventure, Space, First-person Perspective, and Single-player video game owned by Brixton Games.

Mitaka is software for visualizing the known Universe with up-to-date observational data and...

Pioneer is a space adventure game set in the Milky Way galaxy at the turn of the 31st century.

Open Source

Interactive catalog of all known exoplanets (planets orbiting stars beyond our own Solar System).