To date, such information as discussed within this topic are the only ones that have not leaked to the public even considering the entire human civilization, as well as all the technological progress that has been undertaken over time. Specifically, the Alien agenda that would be kept by government and now I guess the far side of Moon. 

The most secretive stuff out there have been hacked into including nuclear codes, top government protected secret information, any personal private data. And, as Trump said any "fat guy sitting in a basement somewhere can do this". But no matter how much, for how long and how well it gets debated, only these other agendas are successfully hidden. 

There exist entire venues of expressions of interest in the alien agenda as said to be coveted and hidden away from the public, yet it seems like we get it go bust. On the other hand we have far more interesting simulations, nicely produced stuff from all over the universe but the far side of Moon. We have hidden cameras anywhere and everywhere, and apparently no one thought of equipping one those little rovers with a little camera as it goes out strolling out there.