Is it too late to point out
from my O-level days, that (IIRC) most educated Romans spoke Greek. In fact doesn't Robert Graves put a brief bit in "I Claudius" as to why it was written in Latin, rather than Greek ?
In which case, I introduce astroployen from 35 years ago, as the Greek word my friends and I invented for "spaceship". After all, we use "Astro*naut*" ...