• Question: how many planets are there in the entire solar system?

    Asked by Demi Parker to Ashley, Bernard, Carsten, MariaMagdalena, Monique on 10 Nov 2015.
    • Photo: Bernard Ennis

      Bernard Ennis answered on 10 Nov 2015:

      According to the Internation Astronomical Union there are 8 planets in the solar system, but when I was a kid there were nine because Pluto used to be a planet back then. It all depends on how you define a planet. This website gives a pretty good summary:
      http://phys.org/news/2013-05-planets-solar.html

    • Photo: Monique Henson

      Monique Henson answered on 10 Nov 2015:

      8! Pluto definitely isn’t a planet. In fact, if you were to define Pluto as a planet, then there are lots of Pluto-like things that would also fit under the description of a planet too. Instead we know think of it as a dwarf-planet. At the moment (I think) we’ve identified 5 dwarf planets in our solar system, but some people think we might find as many as 50.

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