Want to send a message in a satellite to our ancestors (or successors) 50k years into the future? Leave your 6,000 word message here.
Though — given our inability to understand more than a fraction of what our human ancestors were scribbling on cave walls 50k years ago, the idea that these messages will actually be understandable or of interest to anyone (assuming that anyone’s around, or that “anyone” is a meaningful concept then) seems a good an example of 21st Century hubris as any other.
Maybe I’ll send a knock-knock joke.