When mankind eventually leaves the cradle of Earth and ventures forth into the uncharted territories of the cosmos, where, and what form, will our new homes take?

From small viscous meat eaters to vegetarian giants, dinosaurs came in all shapes and sizes. Remarkable new evidence suggests that one dinosaur did not become extinct but evolved into a new animal species we all know today. Discover the missing link between the velociraptor and modern day birds.

'Just Do It: A Tale of Modern-day Outlaws' lifts the lid on climate activism and the daring troublemakers who have crossed the line to become modern-day outlaws. Documented over a year, Emily James' film follows these activists as they blockade factories, attack coal power stations and glue themselves to the trading floors of international banks despite the very real threat of arrest.

1917. People have had enough of the war. Behind the scenes, uprisings are brewing, like the one that toppled the Tsar in Russia; on the front soldiers begin to mutiny as they did at Chemin des Dames in France. German submarine attacks in the Atlantic will finally pull the Americans into the war, but they arrive too late to help prevent the carnage of the Battle of Passchendaele.

This episode explores the wave theory of light as studied by mankind, noting that light has played an important role in scientific progress, with such early experiments from over 2000 years ago involving the camera obscura by the Chinese philosopher Mozi. Tyson describes the work of the 11th century Arabic scientist Ibn al-Haytham, considered to be one of the first to postulate on the nature of light and optics leading to the concept of the telescope, as well as one of the first researchers to use the scientific method. Tyson proceeds to discuss the nature of light as discovered by mankind. Work by Isaac Newton using diffraction through prisms demonstrated that light was composed of the visible spectrum, while findings of William Herschel in the 19th century showed that light also consisted of infrared rays. Joseph von Fraunhofer would later come to discover that by magnifying the spectrum of visible light, gaps in the spectrum would be observed. These Fraunhofer lines would later be determined to be caused by the absorption of light by electrons in moving between atomic orbitals when it passed through atoms, with each atom having a characteristic signature due to the quantum nature of these orbitals. This since has led to the core of astronomical spectroscopy, allowing astronomers to make observations about the composition of stars, planets, and other stellar features through the spectral lines, as well as observing the motion and expansion of the universe, and the existence of dark matter.

In part two, Professor Al-Khalili looks at the 19th century chemists who struggled to impose an order on the apparently random world of the elements. From working out how many there were to discovering their unique relationships with each other, the early scientists' bid to decode the hidden order of the elements was driven by false starts and bitter disputes. But ultimately the quest would lead to one of chemistry's most beautiful intellectual creations - the periodic table.