Elon Musk has officially become the richest person in the world. His net worth has crossed the US$400 billion mark, making him the first person to have that much money. His interests in SpaceX and Tesla have helped boost his wealth in the past year. Subscribe: http://ab.co/1svxLVE ABC News provides around the clock coverage of news events as they break in Australia and abroad. It's news when you want it, from Australia's most trusted news organisation. For more from ABC News, click here: https://ab.co/2kxYCZY Watch more ABC News content ad-free on ABC iview: https://ab.co/2OB7Mk1 Go deeper on our ABC News In-depth channel: https://ab.co/2lNeBn2 Like ABC News on Facebook: http://facebook.com/abcnews.au Follow ABC News on Instagram: http://instagram.com/abcnews_au Follow ABC News on X (Twitter): http://twitter.com/abcnews Note: In most cases, our captions are auto-generated. #ABCNews #ABCNewsAustralia