• Question: why does all the pictures of earth say it is just green and blue when the world is make up of lots of colours

    Asked by cowsgomoo22 to Catherine, Charlotte, Colin, Becki, Rick on 24 Jun 2013.
    • Photo: Colin Swift

      Colin Swift answered on 24 Jun 2013:

      Well the earth’s surface is mainly covered by water (about 71%) – and that will appear blue. Clouds will appear as white (they’ll reflect and scatter the sun’s light). The polar ice caps will appear as white, and the continents green (vegitation) or brown (desert). If you see a picture of the earth as a whole – details such as cities and towns, large buildings etc are simply too small to be distinguished. So the main things we see are the items I have mentioned which cover a large area of the earths surface. By zooming in you’d be able to see details – I can see my car (red!) quite easily on a zoomed in sattelite photo on google earth, but not in a view of the whole planet.

    • Photo: Charlotte Dalton

      Charlotte Dalton answered on 24 Jun 2013:

      All the different coloured things people have made on Earth are tiny compared to all the natural things which are green (plants) or blue (water). Some pictures of the Earth show we are around though, look at http://visibleearth.nasa.gov/view.php?id=55167 to see some cool pics of the Earth’s cities at night 🙂

    • Photo: Rebecca Scott

      Rebecca Scott answered on 24 Jun 2013:

      As Colin and Charlotte said, from space, a lot of the colourful things on Earth are too small to see clearly and so we only see the really large areas of colour. But really it’s just like when you paint a picture and you use several colours to make up different shades of green or blue, and when you are next to the painting you can see all the different shades, but the further away you move, the more the colours appear to blend together into one.

      But light itself is made up of lots of colours and the way we see these is all about how the light is scattered. For example, when the sun shines while it is raining, the light is scattered by water droplets and a rainbow appears. You can make a rainbow yourself at home too. If you get a glass prism and shine a beam of light through it onto a wall, then you can split the light into a rainbow of colours.

    • Photo: Catherine Fontinelle

      Catherine Fontinelle answered on 24 Jun 2013:

      Hi @cowsgomoo22

      It takes all the colours to balance us out, but from space we just get and idea of the big picture, land, atmosphere, seas…

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