Before you install
Before you install, please note that currently, KStars may require quite some disk space, especially on Windows, as it requires KDE libraries to be installed. The installation process will automatically determine which KDE libraries need installation.
These libraries are shared by a host of wonderful applications, including Okular (an awesome PDF viewer), Amarok (a music player like none other), digikam (photo manager), to name a few, that you can also choose to install for very little additional disk space. See KDE Applications for more awesome, free, trusted apps that share these libraries.
Choose your OS
Choose your operating system for specific instructions. If your operating system doesn't provide binaries (executable programs), you may need to build KStars from source code.
Windows 7,8, 10 64bit installer KStars 2.6.0 (Beta)
Use Quick Hash GUI to verify the integrity of the executable file. The following are MD5 and SHA256 hashes:
On most GNU/Linux distributions, KStars can be installed from your distribution's package manager (eg: Synaptic in Ubuntu). If you cannot find a package called 'KStars', you may need to install a 'kdeedu' package that contains all of the KDE Edu suite, which KStars is a part of. Again, uninstall is performed through your package manager. If you need help, you can ask on IRC (#kde or #kde-kstars on freenode. The #kde channel is more active and likely to be of immediate help.)
See this Wiki page for more details.
If you know specific instructions for installing KStars on Mac, please mail the webmasters / the kstars-devel mailing list (kstars-devel at kde dot org), and we'll update the site with your instructions.
See Building KStars from Source for details.