I heard the song earlier today, and poked around looking to see if anything stood out. I never knew there was a film with the (Silent Running) title. I can’t tell if there is any kind of connection or not. Just thought I would throw this out there, in case someone spotted something. https://musingsofamiddleagedgeek.blog/2019/08/23/retro-musings-1972s-silent-running-is-a-space-odyssey-rooted-in-the-earth/