Tim Radford

Solly Zuckerman was one of a group of clear thinkers on both sides of the Atlantic who helped make science a normal part of government policy. He began at floor level in 1940, when the Royal Navy asked him to find out the force at which a leg would break. When a ship hit a mine and blew up, the vertical displacement of the deck was enough to snap the ankles of a seaman standing on it. When a...

Thomas Edison invented himself, and then he invented the legend. He did the first in the usual, recognisably Victorian way, from scratch, with terrific self-confidence, huge energy, astute focus and ferocious determination. He did the second by exploiting a singular gift for self-publicity: introduce a journalist and Edison would produce a soundbite. Some of them slid straight into the dictionaries of quotations and stayed there, and are still daisy-fresh more than a century later. ‘From his neck down a man is worth a couple of dollars a day,’ he once said. ‘From his neck up, he is worth anything his brain can produce.’ He remarked of his friend Henry Ford: ‘This fellow Ford is like a postagestamp. He sticks to one thing until he gets there.’ He had a way of making his recipe for success seem dead simple: ‘I find out what the world needs. Then I go ahead and try to invent it.’‘

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.

On 4 July, the US spacecraft Pathfinder, one of three launched last November, will enter the thin atmosphere of Mars. Though the Martian atmosphere is about 1 per cent of the Earth’s, the buffeting will slow the spacecraft down from 7.5 kilometres a second to about 400 metres a second, or 900 miles an hour – which is slow enough for a parachute to open (rockets will help). Pathfinder will literally bounce into touch, bobbing on a cocoon of inflated airbags, before coming to rest on Martian soil. The touchdown will be in a region called the Ares Vallis, chosen because it seems to be a huge wadi or dried-up watercourse. A hatch will open, and out will pop a little wheeled robot rover called Sojourner, which will beetle about the immediate terrain, examining rock chemistry and reporting back to the lander, which will relay data and pictures back to Earth.

On the first day of Christmas, more bishops will be thinking about global warming than adultery, or so a survey by the Church of England General Synod reported in January … Strange, then, that we hear so little from the Church about the desecration of God’s earth. Perhaps your parish priest needs prompting?