Thanks to Heritage Auctions, we now have a little more info regarding the production of The Young Astronauts. The fruits of Marvel Productions' partnership with The Young Astronauts Council, in the form of an animated series that was intended to air on CBS for the 1985 TV season, but was delayed due to disputes with the YAC's advisor on the production. Attempts to restart the series in early 1986 were for naught as the network cancelled the show after the Challenger space shuttle explosion.
Linked below are background layouts from the series' fourth episode Ghostship, under the production code MP 800-04. Drawn by Disney legend Walt Peregoy, whose work for Marvel around this time included My Little Pony: The Movie, Glo Friends and Moondreamers.