Busy skies

My daughter (mum to the car-vomiter) is on her way to Australia for a week’s work, and I’ve been tracking her flights, being as I'm bored and can’t do much else! She’s been travelling for 24 hours now, has changed in Hong Kong and will be landing soon.
I’m fascinated by how many planes are in the sky at one time, so surely an air traffic controller has the most skilled job in the world?