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Pages

1Where is Mars?2How long will it take to get to Mars?3Getting to Mars4How do rockets get off the ground?5Producing Thrust6What happens when rocket fuel burns?7Your mission to Mars!8Our need for oxygen9How oxygen gets to our cells10The effects of gravity11How low gravity affects bones12Preventing bones and muscles from becoming weak13Living and working in space14What do astronomers know about Mars?15A space-craft view of Mars16Exploring Mars17Energy for exploration18The rocky surface of Mars19More about the surface of Mars20The Martian atmosphere21The importance of water22The water cycle on Earth23Is there water on Mars?24Surviving on Mars25Your Martian home26Farming on Mars27Soil on Mars28Plants for Mars29Getting energy on Mars30Where will you go next?

Practicals

1Modelling the solar system in the school yard2Rocket Practical3Investigate the Energy in Fuels4Making a Telescope5What factors affect the output of a solar cell?6Modelling Diffusion7Examining Slides of Blood8What bones are like without calcium salts9Flame Test to Identify Metals10The Different States of Water11Water Purification for Human Consumption12Factors Affecting Germination13Solar Cells for Devices14Mars Bingo
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An image of Earth and Mars A ruler, for measuring distance Earth Mars

Even though Earth and Mars are next door to each other in the solar system, they are still a very, very great distance apart! The actual distance changes depending on where exactly each planet is within its orbit.

Click on the activity symbol to find some questions in which you will use the first picture on this page, along with the rule shown

Try working out the answers to the following questions before clicking on the 'Show Answer' buttons – how many did you get right?

1
Use the ruler in the picture to measure the distance between the two planets in 'ruler units'.
10 units
2
If each 'ruler unit' is actually 10 million km, what is the distance between the planets in km?
10 x 10 million = 100 million
3
Because distances in space are so great, astronomers use 'astronomical units' (AU). If one astronomical unit is 150 million km, what is the distance between Earth and Mars in astronomical units?
100 million ÷ 150 million = 0.67 AU
A Rocket

If you were able to get into a rocket, and set off for Mars, how long would it take you to get there? Would it take hours? Days?


What do you need to know to try to find the answer to the previous question?

We need to know how far away Mars is

We need to know what the rocket is like, and how far and fast it can travel

Research activity

Category
Speed
(km/h)
Speed
(km/h)
(rounded value)
Speed
(mph)
 Example Vehicle Pilot Date
7,258
 7000 4,510 03/10/1967
870
 900 540
Ivan Soukhomline
 1960
Helicopter
401.0
 400 249.2
John Egginton
 11/08/1986
58,536
 60,000 36,373 (unmanned) 19/01/2006
46,440
 50,000 28,860 (unmanned) 15/01/2006
39,896
 40,000 24,790
Apollo 10 CSM Charlie Brown
Thomas Stafford,
John W. Young,
Eugene Cernan
 26/05/1969

Look at the data above on different flying craft that human beings have designed, then use the data to answer the following question.

Which one would you choose to set off for Mars, and why?

manned spacecraft (Apollo 10) because this is the fastest craft that can contain people

To work out how the time taken to get to Mars, we need to compare the distance we need to travel and the speed of the craft we are using. We can use the simple formula:

Time = Distance ÷ Speed

When we use this formula, we need to be careful that the units of distance are related to the units for speed. So, for example, if the distance is given in km (kilometres), then the speed should be in km/h (this means 'kilometres per hour', and not in mph ('miles per hour'). km/h can also be written km h-1).

Example

Try working out the answer to the following question before clicking on the 'Show Answer' button – did you get it right?

1
I need to travel to a town 100 km away. The speed of my car is 50 km/h. How long will it take me to get to the town?
Time = Distance ÷ Speed

Time = 100 km ÷ 50 km/h

So, time = 2 h

(i.e. 2 hours)

Question

Try working out the answer to the following question before clicking on the 'Show Answer' button – did you get it right?

1
If Mars is 100 million km away, and the fastest manned rocket we have travels at 40,000 km/h, how long would it take us to get to Mars?
Time = Distance ÷ Speed
Time = 100,000,000 km ÷ 40,000 km/h
So, time = 2500 h

What is this in days?

One day has 24 h, so number of days is:
2500h ÷ 24h = 104 days (approximately)