The best Star Map alternative to Google Earth is KStars, which is both free and Open Source. If that doesn't work for you, our users have ranked more than 50 alternatives to Google Earth, but unfortunately only two of them are Star Maps.
Open-source astronomy software offering accurate night sky simulation with 100 million stars, Ekos astrophotography suite, stellar observation planner, "What's up Tonight" tool, FOV editor, and a variety of celestial catalogs for comprehensive astronomical exploration.
Aciqra (uh-SEE-kruh) is a free and open source virtual sky map and planetarium which tracks and displays astronomical bodies including planets, nebulae and stars to an accuracy of a fraction of a degree for thousands of years into both the future and the past.
Germany
EU
It’s a planetarium program, not a maps or atlas program.