Red Sun Paradise
They'd managed to defeat the villain through a clever plan and teamwork, despite the unhealthy dose of concentrated red sun radiation he'd managed to hit Jon with. Since then, Jon had been recovering his powers, bit by bit, but something in the red sun weapon was making it take time. It was going to be a while before he could fly them home, and the lingering radiation, while not harmful to Annie, was enough to interfere with coms. They're stuck - until he can soak up enough sun to recover full flight capacity. To that end, he's down to just the red shorts, and partaking of an unusual activity for him - sunbathing.