• Question: when would the world come to an end

    Asked by tuenchi1 to Steve, Sam, Katie on 21 Jun 2011. This question was also asked by annathornton28, lucylu, hannah1999.
    • Photo: Steven Daly

      Steven Daly answered on 19 Jun 2011:

      There is a definite answer to this, that the world will ‘end’ when it is swallowed by the sun in about 4 billion years. As stars get older they start to use helium as a fuel instead of hydrogen, and when they do this it makes them swell up to become red giant stars. The Sun will probably get to be about as big as the orbit of Mars.

    • Photo: Katie Marriott

      Katie Marriott answered on 20 Jun 2011:

      I agree with Steven! It will end but it will be a long time from now.

    • Photo: Sam Tazzyman

      Sam Tazzyman answered on 21 Jun 2011:

      This is a nice picture showing the expected life cycle of the Sun, and where we are now. When it gets to 9 or 10 the Earth will have been swallowed up: