This is beautifully designed and engaging and potentially a fun way to learn things! Amazing work.
Some things you could add to make it stickier:
1. Have a natural end where you "win" - possibly I just didn't hit this, it's the kind of game I'd play in bed in the morning as long as the play time was similar to Wordle and the other NYT games.
2. Have facts show up when you get something right! Could literally just be the opening sentence from the article and a link to the article. This extra context stimulates curiosity - I'd love to be able to have "Space physics? That doesn't sound like a real thing..." and then have the hat guy pop up and go, "You cracked it chief. Space Physics is the study of high atmosphere plasmas."
EDIT: for comparison, have a look at Metazooa - https://metazooa.com/ - which did this very well.
I played the Map mode and got the same page several times, and then the game ended with half my "life" left. It was really fun but I passed a lot of rounds just on memory
Really fun, took me over 20 articles before I realized I can just type the letters on my keyboard instead of clicking them one by one with my mouse :^).
This is a very clever idea. I've toyed with the idea of making a multiple site mystery challenge in the past, a bit like a geo game with real world tagging and drop boxes.