The theory of Némesis, a star that orbits the Sun and causes catastrophic events is explored. Nemesis is a hypothetical red dwarf or brown dwarf, originally postulated in 1984 to be orbiting the Sun at a distance of about 95,000 AU (1.5 light-years) somewhat beyond the Oort cloud, to explain a perceived cycle of mass extinctions in the geological record, which seem to occur more often at intervals of 26 million years.

Professor Brian Cox journeys across the vastness of time and space revealing epic moments of sheer drama that changed the universe forever.
The series begins this epic exploration of the cosmos with a hymn to the great luminous bodies that bring light and warmth to the universe: the stars. It is estimated that there are two hundred trillion stars in the universe, each playing their part in an epic story of creation- a great saga that stretches from the dawn of time, with the arrival of the first star, through diverse generations until the arrival of our own star, the sun, and a civilization that has grown up in its light.

There is an extraordinary range of temperatures in the universe. This program examines the extreme lower temperature range, the temperature we live in and below, explaining how cold is essential for the formation of habitats suitable for life. Explore icy planets and moons, discover the role of cold in the Universe, and learn about the importance of ice to the development of habitable worlds.