Cartes du Ciel is free software released under the terms of the
GNU General Public License
Bellow installation procedure uses only command line approach, because this is the simpler way to follow instructions just by copy-pasting the commands in terminal. This instructions are tested with the currently supported versions of Ubuntu.
sudo apt-add-repository 'deb http://www.ap-i.net/apt stable main'
Note: If you would like to install development version of Skychart instead of stable version, then replace word “stable” with “unstable” in above and bellow command.
sudo apt-add-repository --remove 'deb-src http://www.ap-i.net/apt stable main'
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys AA716FC2
sudo apt-get update
sudo apt-get install --no-install-recommends skychart
sudo apt-get install skychart-data-stars skychart-data-dso skychart-data-pictures
You will also find the Skychart button in the main menu.