Celestia installation on Debian-based GNU/Linux distributions.

curl -s https://celestia.space/packages/celestia.key | sudo apt-key add -
echo deb https://celestia.space/packages SUITE COMPONENT | sudo tee /etc/apt/sources.list.d/celestia.list

Replace SUITE with your distribution codename (stretch, buster, xenial, bionic, focal). If it's either xenial or bionic, replace COMPONENT with universe, otherwise use main.

To determine your distribution codename, you can run the command:

lsb_release -a