Complex sentence: A member world of the Terran Hanseatic League known for its dismal climate and although a plan was forwarded to use orbital mirrors to warm the surface of the world, it was acted upon as it was deemed impractical.
Split into simpler sentences: A member world of the Terran Hanseatic League known for its dismal climate. Although a plan was forwarded to use orbital mirrors to warm the surface of the world, it wasn't acted upon as it was deemed impractical.