Earth's atmosphere [comprehension quiz],

The atmosphere is a protective layer of gases which surrounds the Earth. If the Earth were the size of an apple the atmosphere would only be as thick as the apple skin. This is an actual view of the atmosphere as seen from space. It is this tiny layer which we are damaging with our pollution. The atmosphere is made up of 78% Nitrogen, 21% oxygen [the bit we breathe] and 1% of other gases. It also protects us from the harmful rays of the Sun's radiation. At the same time it traps some heat in keeping the Earth warm much like a greenhouse does. The atmosphere is split into 5 layers. Troposphere. Stratosphere. Mesosphere. Thermosphere and Exosphere. Troposphere - Ozone Layer. Stratosphere - weather balloons. Mesosphere - meteors. Thermosphere - Northern Lights. Exosphere - Space Station. You can remember these names in order by using a mnemonic [silly sentence]. The Silly Monkeys Tickled Elephants

1. What does the atmosphere do? helps reflect all of the Sun's rays provides the oxygen we breathe forms a protective layer around the Earth 2. How is the atmosphere like a greenhouse? it helps us grow crops it traps some of the Sun's heat you can see through it 3. What percentage of the atmosphere is oxygen? 21 31 41 4. In which layer might you find a weather balloon? stratosphere thermosphere exosphere 5. From what does the atmosphere protect us from? insulation radiation ionization

There are 9 pictures in a grid. As you hover over each picture a blue screen appears on which there is some information about what is being shown in the picture. Read this information and look at each picture to make sure you understand what is being shown. If you want to check how much you understand try the quiz on the right hand side. To start the activity again just refresh the page.