Among the top 10 richest people in the world, only Bill Gates and Warren Buffett added to their fortunes in this period, according to the Bloomberg Billionaires Index.

The 20th century saw a number of staggeringly wealthy individuals, but none of them could hold a candle to the wealth of John D. Rockefeller who controlled 3% of America's entire wealth

It was a post from Elon Musk, originally published hours earlier. “This is the first time humans have been in orbit around the poles of the Earth!” he wrote. Underneath his post was a video shared by SpaceX—footage of craggy ice caps,