• Question: What is earths radious ?

    Asked by shasow15 to Colm, Eoin, Joseph, Lauren, Stephen on 17 Nov 2013.
    • Photo: Joseph Roche

      Joseph Roche answered on 17 Nov 2013:

      It’s about 6,371 km. Comparing that to the Sun (695,500 km) makes the Earth seem very small.

    • Photo: Eoin O Colgain

      Eoin O Colgain answered on 18 Nov 2013:

      It would be surprising if the Earth was a perfect sphere and indeed, its not, so the “radius” changes. The Earth is flatter at the poles and as a result the weight of a given person at the north or south pole increases slightly.

    • Photo: Stephen Scully

      Stephen Scully answered on 18 Nov 2013:

      The Earth’s radius is about 6 and a half thousand kilometres.

    • Photo: colm bracken

      colm bracken answered on 18 Nov 2013:

      The other guys answered this one well so I will just try to add a fun fact. Because the Earths radius varies as you go from the equator to the poles then the strength of gravity also varies. And since Einstein tells us that time travels at different rates for different strengths of gravity then people who live at the poles feel time travelling slower than people who live at the equator. The difference is very small but it is there. In fact if you spend some time up a high building then time will be going slightly faster for you than for the rest of us. You are then kind of travelling back in time relative to the rest of us!

    • Photo: Lauren Mc Keown

      Lauren Mc Keown answered on 22 Nov 2013:

      it’s 6371 km as the guys have said. So basically if the Sun were a football, the Earth would roughly be the size of a pea. That’s a big enough difference isn’t it!