How do you get off Astro Knights Island?

Answer 1

Park your Spaceship on top of the Castle

To leave Astro Knights Island (without completing the quest), return to Arturus on the planet Poptropica (X-56 Y-52), landing there and not on the Pewter Moon. Your spaceship will park on top of the castle.

Shortcut to another Island (to play another island or an ad-game)

To "quickly" leave Astro Knights Island, you can use the Haunted House. While previously it was free and now may not open, new users can buy it from the Store for 350 credits. Select it from your Store Items list, enter, and then leave. You should be at the Island Map, from which all current islands can be selected. When you are ready to resume the Astro Knights quest, return to the island by blimp and enter Arturus. Your spaceship will be parked on top of the castle and you can return to space with the same status as you had previously acquired.