00.30 — 02.30

Introduction. Gravity as a force that has shaped us and all living things, and the Earth we live on. Why does gravity do what it does, and what are the long-term consequences for the Universe?

02.30 — 06.30

How the planets of the Solar System have been shaped by gravity. The law of gravity applies everywhere in the Universe. Isaac Newton, who observed an apple falling and inferred the law of gravity; and how his understanding of this fundamental force led on to the Industrial Revolution.

06.30 — 10.45

The effects of gravity on the constructed world: earthquakes; volcanic eruptions; gravitational tugs; meteorites. The use of gravity mapping to look inside the Earth’s crust.

10.45 — 17.10

The gravitational constant G is difficult to measure precisely. Gravity as a cumulative force that acts over very long distances — G as the key to cosmic unity.

17.10 — 25.00

How gravity allows us to shape ourselves, and is like a sixth sense. The growth of the body as a struggle against gravity; and learning to walk as one of life’s great challenges.

25.00 — 35.30

Investigating what happens when you take gravity away. The effects of zero gravity on muscle, bone and internal organs, and the implications for long-term space travel or living in space. How the absence of gravity could trigger evolutionary change.

35.30 — 41.00

Gravity and the Universe. The problems faced by astronomers trying to determine whether the Universe will expand forever. Einstein and the General Theory of Relativity; the inclusion of a constant so that the theory fits the astronomers’ model of a static Universe. Hubble’s discovery that the Universe is in fact expanding throws doubt on Einstein’s ideas.

41.00 — end

The question of whether the rate of expansion is slowing, or whether the Universe will expand forever. Evidence from white dwarfs reveals that the Universe is expanding at an ever-faster rate. How Einstein may have been right after all: his cosmological constant as a sort of anti-gravity, a ‘push’ factor that would accelerate the expansion of an already expanding Universe. The logical outcome: a cold, dark end to the Universe.