Cosmic!

Tim Radford

• Korolev: How One Man Masterminded the Soviet Drive to Beat America to the Moon by James Harford
  Wiley, 392 pp, £24.95, June 1997, ISBN 0 471 14853 9
• Countdown: A History of Space Flight by T.A. Heppenheimer
  Wiley, 398 pp, £24.95, June 1997, ISBN 0 471 14439 8
• Something New under the Sun: Satellites and the Beginning of the Space Age by Helen Gavaghan
  Copernicus, 300 pp, £15.00, December 1997, ISBN 0 387 94914 3
• Space and the American Imagination by Howard McCurdy
  Smithsonian, 294 pp, £19.95, November 1997, ISBN 1 56098 764 2

For every action, there is an equal and opposite reaction. When you light the blue touchpaper on Guy Fawkes night, the force goes downwards and the rocket goes upwards. But gravity tugs rockets, apples and everything else downwards at a rate of roughly thirty feet per second per second, so to climb out of gravity’s well, and make it into freefall in orbit, a rocket has to get up to a speed of more than five miles per second – ‘escape velocity’, it’s called.