I am getting an error when installing Kstars on a rock pi4 c+
rock@rock-4c-plus:~$ sudo apt install indi-full gsc returns
[sudo] password for rock:
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Package indi-full is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package gsc is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'indi-full' has no installation candidate
E: Package 'gsc' has no installation candidate
E: Unable to locate package returns


Any Ideas??? ... Bruce