• Question: Why is the Earth's core hot? What caused it to heat up? Is it still heating, or now cooling?

    Asked by khughes08 to Hermine, Katy, Laura, Nathalie, Paula on 17 Jun 2010 in Categories: .
    • Photo: Katy Mee

      Katy Mee answered on 16 Jun 2010:

      A lot of the heat in the Earth’s core was created when the Earth was originally formed, which was caused by accretion (i.e. bringing together) of small bodeis to form the young Earth. A lot of heat is generated by the collision of these bodies and the reason that it has remained hot for 4.5 billion years is partly to do with the relatively slow rate at which Earth loses heat (through convection and conduction). Added to this are other forces which continue to create heat within the Earth’s core, such as decay of radioactive elements.

      This article is really easy to read and pretty much answers all your questions, and in more detail than i can:

      http://www.scientificamerican.com/article.cfm?id=000B2C71-BCF0-1C71-9EB7809EC588F2D7

    • Photo: Laura Dixon

      Laura Dixon answered on 16 Jun 2010:

      The molton lava in the core?
      I believe the core has started to cool down now….sorry I only have a basic knowledge of this subject! 🙂

    • Photo: Nathalie Pettorelli

      Nathalie Pettorelli answered on 16 Jun 2010:

      Hi there again,

      There are three main sources of heat in the deep earth: (1) heat from when the planet formed and accreted, which has not yet been lost; (2) frictional heating, caused by denser core material sinking to the center of the planet; and (3) heat from the decay of radioactive elements.
      As far as I can see on the web (by the way, did you know that a lot of the questions you asked are asked exactly the same way as some of the questions found through various websites? 🙂 see for example http://www.scholarshipsinindia.com/answer/hot_core.html), it’s cooling (http://en.wikipedia.org/wiki/Inner_core).
      Not too bad for a conservation biologist, isn’t it? 🙂

    • Photo: Paula Salgado

      Paula Salgado answered on 16 Jun 2010:

      1. Not known exactly

      2. Best guess is friction at the formation of the planets generated heat that got trapped by rock

      3. It’s now slowly cooling

      Short and simple, I hope 😉

    • Photo: Hermine Schnetler

      Hermine Schnetler answered on 17 Jun 2010:

      The heat in the core is believed to be created from the particles that were brought together through gravity. When this happened there was a lot of friction and collisions.When two objects collide and rub they generate heat, hence the particles from before. The earths core appears to be cooling very slowly just now.

Comments