They were in the UK (Why else would there be so much ENGLISH?) plus there was a picture of Blackpool, Pleasure Beach, with the caption they should be there. Also the Heathrow Express picture was a pretty blatant giveaway.
Now India looks like a strong contender with the last clue given, and the park that was found with Nitro in it. I was thinking China for a minute due to the "Space Junk" clue and the recent failure of their moon rover, but there's not other clues I can connect.
Also, have confirmed they are not in my house, either.