Fuck you mean Gundam had like... a story, and themes, and gay people, and whatever the hell else? I just thought it was an elaborate marketing ploy to buy the model kits! Like transformers.
To answer your questions:
1. Occasionally, people can be psychic. They’re called Newtypes and literally everyone tries to weaponize them at some point. A lot of them are kids because they’re a relatively recent phenomenon that seems to be related to growing up in space. I think the oldest one is Chalia Bull who is 33 when we meet him in 0079, meaning he was born in 0046.
2. It was supposed to hit a place in the Amazon Rainforest called Jaburo, which was the headquarters of the Earth Federation; but the space colony broke apart during the battle being fought to stop it from doing that. The largest piece of debris was the entire front half, and that’s what hit Sydney instead, sinking 16% of Australia on impact. Think about what twice the mass at a much steeper angle would have done to the middle of the Amazon Rainforest
3. The Universal Cemetery Century does not really have good guys, just varyingly terrible flavors of bad guy. Zeon did that to get the space colony they blew up Australia with, the Titans (Space SS, Space ICE is a different thing called the Manhunters and they come a bit later) did that to stop a protest against the Earth Federation government. Gas weapons are preferred because space colonies are enclosed environments with a known volume.
I don't... I don't know what to do with this information.
This series is metal as hell.