These scientists are part of a global race. It's been running for over a decade... to build a mythical machine, the holy grail of calculations - a quantum computer. Remarkably, first-generation quantum computers have started to appear. Indeed, earlier this year, Google bought one. The D-Wave 2.

China's last empire, the Qing, lasted from 1644 to 1912. It began in violence and war as the Manchus swept down from the north, but invaders became emperors, with three generations of one family ruling the country. Among them, Michael Wood argues, was China's greatest emperor - Kangxi. Under the Qing, China doubled in size to include Xinjiang in the far west, as well as Mongolia and Tibet, creating the essential shape of China today. The new dynasty tolerated a diversity of cultures and religions, including Islam. In Kaifeng, Michael visits a women's mosque with a female imam, a delightful scene that ends with laughter and selfies! The Qing also undertook huge cultural enterprises. At a traditional printing house where the wood blocks are hand-carved, we see how the Complete Tang Poems were reproduced - all 48,000 of them. We travel through the wintry countryside to a remote village where a hardy audience watch open-air opera in the snow and visit a painter's studio, and 'storytelling' houses in Yangzhou. In the 18th century, China was arguably the greatest economy in the world, and we get a fabulous sense of the rich culture that came with prosperity. But then came the clash with the British, in the first Opium War, when a British expedition destroyed the Qing navy and extracted territory and trading rights. We leave with a glimpse of the future. 'Every dynasty has risen and declined,' says Michael, 'and has needed new life to regenerate, and this time the catalyst was the British.' Among the ports China ceded was an almost uninhabited island, Hong Kong, one of today's greatest financial centres, and Shanghai, a small town then but now one of the greatest cities in world.

A new era of space is dawning where small satellites no bigger than a shoebox will be deployed not in one or twos, but in their thousands - referred to as satellite swarms. It's been described as the democratization of space. What was once the preserve of governments and superpowers is evolving into a truly global industry. The catalyst for this dramatic change is this new generation of satellites.