In 1999, the population of the earth reached six billion (6,000,000). It will probably reach eight billion in another fifty years. In the future, we may have to find new places for people to live because there might not be enough room on Earth. People may go to live in space colonies or they might go to live on the other planets. Scientists think that Mars will be the best place to live because it is the closest planet to the earth and it will be easier to travel there. The temperature, gravity and environment are not too different from earth. Another advantage is that there is probably water there.
Before people can live on Mars, we need more information about it. The North American Space Agency, NASA, is planning to send more space probes to explore Mars. Space probes are better than manned space craft because space travel over long distances is difficult and dangerous for humans and takes a long time. There are, of course, no people on board space probes and scientists on earth send signals to the probes to control them. This takes a long time. When Pathfinder space probe landed on Mars in 1997, it took 11 minutes for signals to travel to and from Earth. Another difficulty is that the space probes do not have a lot of energy to send their information back to Earth.
It is important to improve communications between Mars and Earth. NASA scientists want to have communications satellites around Mars. When they are in position, they will help scientists to send and receive signals from the exploration probes more easily. Cameras on the satellites will photograph Mars and also scientists will make better maps. Communication satellites will also help NASA with its plan fro a space probe to bring rock back from Mars.
When more information is known about Mars, humans might be able to explore the planet themselves. NASA scientist Chad Edwards said: “If we have to carry everything with us, we’ll never get there.” NASA’s plan is to send unmanned space probes first that will produce energy, water, fuel, and air on Mars. Humans will then use these supplies during their stay there.
Ref: Michael Harris and David Mower, World Club Students’ Book, 2002.