I always assumed that was the firing of the Halo array.
I have to say, the more the back story of the Forerunners are fleshed out - the Librarian, the Composer, etc. - the less interesting and compelling it becomes to me. There was a powerful simplicity to the story of human ancestors sacrificing themselves to stop an unstoppable threat, while sheltering and preserving the seeds of life to blossom in the aftermath. I've always found that really powerful.
This whole business with the Composer, the Librarian planting seeds so that everything that has a happened has been just as she intended, people doing what they are destined to do, Forerunner no longer being human ancestry but this mutating race of humanoids at war with actual humans....not so much. It's just needlessly convoluted.
Yeah, the story is starting to veer dangerously close to "magic" than sci-fi. From Reach to Halo 3, it was all very much plausible that this could be an actual alternate future. Now we're getting destinies and stuff. Uhh.....
How do you know?
Electrical sockets are generally installed at two standard heights: 12", or 18". Eyeballing the height of the Kat cosplayer with the height of the socket off the ground gives me roughly 5'2". The other standard height would make her 7'5", so I'm going to go with the first one
I almost became an architect, going fairly far into it but not quite college. Had to make hundreds of houses in AutoCAD for practice and cleaning up AutoCAD designs for firms, so I have a bunch of not-greatly-useful-in-day-to-day factoids of houses seared into my head.
I think this has also influenced my map design. I see other maps made and they look so organic.. my maps look very architectural and 'real'. When I make games, I always model the world or machines, I can't figure out how to model people or organic creatures.