On planet Earth there are at least two archipelagos known as “The Channel Islands.” Frankly, I'd be somewhat surprised if there aren't more. One is located in an arm of the Atlantic Ocean that separates France and the UK known in English as “The English Channel” or simply “The Channel.” It's traversed (or is it subversed) by the Chunnel. Its eight Channel Islands are home to about 168,000.
The other Channel Islands are in an arm of the Pacific Ocean called the Santa Barbara Channel. Being located in California they are are often distinguished from their Atlantic counterparts by their being referred to as the Channel Islands of California. There are also eight islands in this archipelago although they’re only home to about 4,000 people. In some ways they have more in common with another archipelago, the Galapagos Islands of South America. Both developed in relative isolation which allowed for an independent evolutionary processes. In the Channel Islands' case, that process led to the development of at least 145 endemic species.