What scientists are attached to is journeys into the unknown and discovering things that are completely unexpected and baffling and surprising.

When we look out into space, we are looking into our own origins, because we are truly children of the stars.

(On the energy radiated by the Sun) It's four hundred million million million million watts. That is a million times the power consumption of the United States every year, radiated in one second, and we worked that out by using some water, a thermometer, a tin, and an umbrella. And that's why I love physics.

We are the cosmos made conscious and life is the means by which the universe understands itself.

Deeper understanding confers that most precious thing - wonder.

Skepticism must go hand in hand with rationality. When theories are shown to be false, the correct thing to do is to move on.

At every stage of understanding the universe better, the benefits to civilisation have been immeasurable. None of those big leaps were made with us knowing what was going to happen.