Imagine how disappointed the aliens will be to find our disc full of the boring old "discoveries" of a barely space-fairing species. Nothing to see here, move along.
Besides, you have all the character bios for the full Marvel universe(s)...
I'm only half being sarcastic, as I've gotten lost in some of those articles trying to figure out who someone is... while I'm not sure of the encyclopedic value of those articles, they definitely have some entertainment value. For that matter, it may be worth clarifying fictional characters from those that are historic, or based on historic events.
One concept that always got me is the premise of an alien culture without sarcasm. They would have a very hard time with human culture/history.
I do sometimes wonder what the future people are going to make of the hundreds of thousands of words of argument over en-dash, em-dash, hyphen and minus.
Mexican-American war had twenty thousand words of discussion over what dash to use, and that knowledge isn't transferable even to other dashes used in title on WP.
Here's 15,000 words on dashes. The result? No concensus.
Memes, too. "You mean ancient humans argued as an interconnected species over the color of a dress?"
I'm waiting for the meme that conclusively starts a war. The assassination of Archduke Franz Ferdinand in 72 point Impact. That'll be a fun one for future history books to explain.