• Question: Why is earth the only planet people can live on?

    Asked by J.Johnson to Zena, Jared, Isabel, Ian, Frank on 16 Mar 2015.
    • Photo: Isabel Pires

      Isabel Pires answered on 16 Mar 2015:

      As far as we know, the Earth is the only planet that has an atmosphere that contains oxygen, needed for life, water in both solid, liquid and gas form, and has relatively shot range of temperatures. Mars, for example, lacks an atmosphere, and the temperature ranges can vary by 100s of degrees! And in Venus, the atmosphere is mostly CO2, which is toxic for humans in high concentrations.

      However, there might be other planets in the University with similar conditions, we just don’t know about them yet. And who knows, there might be life there!

    • Photo: Ian Sandal

      Ian Sandal answered on 19 Mar 2015:

      As Isabel says there are many billions of other planets in the Universe and some of these could (and probably do) have life on them.

      We also have to be careful as to what we describe as life. As Isabel said all the other planets we know wouldn’t allow Earth based creatures to live on them, but other forms of life that can survive in toxic gases or extreme temperatures may exist on them.

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