Courtesy NASA/JPL-CaltechWritten for the KidsKnowIt Network by: Gemma Lavender, MPhys, FRAS
You may have been told by your parents that you are on another planet when you are either day dreaming or have said something silly, but have you ever wondered what it would be like to live on another world? How different would it be compared to life here on Earth?
Out of the remaining seven planets in our Solar System, we need a world that is not too hot, not made of gas and nor so far away from the Sun that it is too cold. Can you guess which planet that is? The answer is, of course, our red, rocky next-door neighbor, Mars. But while it is the closest planet to us, it takes a very long time to get there – just imagine a car journey with no stops that takes up to 9 months!
Mars is lighter than the Earth and, because of this, you would be about 38% lighter there than you are here. That means that if you weighed 100 pounds, then you would weigh only 38 pounds on Mars. Because of the difference in gravity and the red rocky terrain, care must be taken when landing your rocket onto the surface of Mars. However, while you have succeeded in getting to the planet as well as landing, the hard work and watching out for your safety is not over. You need to make things more efficient and cheaper and that would require you to stay on the red planet for good. Would you and your friends be able to live up to the challenge?
Humans would need a buggy to travel across Mars’ rocky surface. Image: NASA
Mars and Earth are not just different in color, they are made of different materials – Mars’ surface is covered in dry iron oxide dust (just like the rust that you can find on an old car), whereas our home is mostly wet with water. Since the air on Mars is thin and made of carbon dioxide - the air that you breathe out rather than breathe in - you will need to wear a spacesuit, and because the red planet hardly has an atmosphere, you would need to protect yourself from the Sun’s radiation that here on Earth our thick atmosphere protects us from. Can you think of something that will give you extra protection from these harmful rays while wearing your spacesuit?
Mars’ surface has many mountains and volcanoes. Image: NASA
Your main task on Mars would be to make it nice and safe for your family and friends before their arrival on the red planet. But they don’t want to wear a spacesuit or walk around with an umbrella to keep themselves safe from the radiation, they want to be able to live life as they do on Earth. The only solution would be to make Mars like Earth – but how?
Terraforming is the answer! At the moment though, this is an imaginary process made up from a combination of real science and science fiction. Terraforming involves changing the atmosphere, temperature and surface of a planet just to make conditions much more comfortable for you, your friends and family. Playing your favorite outdoor games would be impossible on the red planet without terraforming – especially in a clunky spacesuit! Because Mars was very much like Earth in the early stages of its history, astronomers believe that this planet is the easiest to transform into a world very similar to Earth. There would be two important changes that would be up to you to make. Firstly, so that you are safe from the radiation and are kept warm, you would need to change Mars’ atmosphere. Since the atmosphere is made of carbon dioxide, you would need to make sure that Mars gets enough water as there is not enough water currently on the red planet. However, in order to get more water, you would need to send a search party to other places in the Solar System - icy asteroids and comets, and the icy moons of the gas giants Jupiter and Saturn, are really good places to look!
Getting enough water to Mars is a very hard task, but with the combination of carbon dioxide, water and heat from the Sun, you and your friends have made the pressure much higher on the red planet - this means that you are able to take your pressure suit off! You have also melted ice on the red planet, making about half of the surface much warmer and wetter – with the plants you have brought from home, you are able to take care of them on the surface. But how can plants help us to make Mars a friendlier place? The flowers that you might have on the window ledge at home or in your garden love carbon dioxide and they are more than happy to turn Mars’ air into oxygen for you!
You have made the red planet much more homely for everyone, but your task is still not over. You also need to add more heat to the planet as well as another protective shield around you to stop other harmful rays from reaching you. It is time to build a home, just like your home back on Earth which you might use to stay in the shade on a hot summer day! On your travels on the surface, you have come across volcanoes. When volcanoes drain lava, it often happens along a tunnel called a lava tube. Realizing that some of the volcanoes could be inactive, you head off towards the largest volcano in the Solar System, Olympus Mons, to make not just yourself at home, but the people making their way from Earth at home too!
In 2007, NASA's Spirit Rover on Mars captured an image of a rock that is shaped like a human. This is quite a fascinating find. However, it turns out that this rock is estimated to only measure about 2 inches (5cm) tall. It is believed that the unusual shape of this rock was caused by wind erosion.