The art style is identical to Captain Harlock. I bet they were done by the same artist, writer and producer. Looking at the wiki, there are definitely some crossover episodes, too. If you've never watched Harlock, you should. Back when television was episodic and non-linear, Harlock, as well as Star Blazers(to a lesser degree), serialized their episodes to have one continuous and developing plotline. Anime was intelligent and like reading a great novel, very sophisticated with mature themes. Definitely like nothing else on American TV at the time, and the best part was us kids got to enjoy those shows while the adults were oblivious they existed.
"Kids shows" anime was not.