Celestia

About

Celestia is a Free and Open Source application developed in the United States for real-time 3D visualization of space, offering a detailed model of the solar system, over 100,000 stars, and more than 10,000 galaxies, alongside an extension mechanism for adding further objects. This planetarium and space simulation tool, which allows users to explore astronomy, stars, and simulate space travel, is available on Mac, Windows, Linux, PortableApps.com, Android, iPhone, iPad, and visionOS. The project maintains a presence on GitHub (CelestiaProject/Celestia), Facebook, and Twitter. User reviews commend Celestia as a "very nice software" and "the best simulator out there" that runs well even on older computers. However, some reviews highlight concerns about its development status, noting the latest release was from 2011 and that its website/forum had become unavailable, suggesting potential project inactivity.