ThunderCats - Season 1 Episode 15 The Time Capsule
Overview: Lion-O becomes homesick, and his memories of Thundera are almost nonexistent. Jaga appears to Lion-O and tells him that on their spaceship, they brought with them a time capsule which contained a recording of Thundera and its history up to the time it was destroyed. The Thundercats set out to search for their time capsule.