Located perfectly in Hawaii's Kipu Falls along the stream of Huleia lies what perhaps is the most dangerous 'pool' ever seen. Locals say it's either a swim of a lifetime or something that can take your life. Others call it "the pool of death".
Yes, it's only micrograms of difference, but it's still really weird: until 2018, the kilogram is defined as "the weight of this physical object". So what happens when that object changes?
Heathrow, London, UK. The Concorde stopped flying in 2003. This was filmed a couple of weeks before the last flight. The loud noise even sets off a car alarm.