By now, a rocket will have set off on its 35 million mile trip to Mars and scientists must be waiting anxiously for the results. The rocket will be travelling for six months before it reaches the planet.

It contains a number of scientific instruments, including a television camera. Any pictures that are taken will have to travel for three minutes before they reach the earth. If the pictures are successful, they may solve a number of problems about Mars and provide information about the markings on its surface which, nearly 100 years ago, the astronomer, Schiaparelli, thought to be canals.

It will be a long time before any landing on Mars can be attempted. This will only be possible when scientists have learnt a lot more about the atmosphere that surrounds the planet. If a satellite can one day be put into orbit round Mars, scientists will be able to find out a great deal. An interesting suggestion for measuring the atmosphere around Mars has been put forward. A rubber ball containing a radio transmitter could be dropped from a satellite so that it would fall towards the surface of the planet. The radio would signal the rate which the ball was slowed down and scientists would be able to calculate how dense the atmosphere is. It may even be possible to drop a capsule containing scientific instruments on to the planet's surface. Only when a great deal more information has been obtained, will it be possible to plan a manned trip to Mars.