system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is the record on voyager plated in gold?
gpt
To add, the record is copper, plated in gold, and then plated in U-238. The reason to make it all metal is that vinyl couldn't possibly survive the harsh environment of space without quickly decaying, and the uranium, with a half-life of 4.468 *BILLION years*, is there so optimistically, a civilization who discovers the record can date it's age.