If the number of planets in our solar system were squaered, there would be this number of planets.

If you don't count Pluto ( or the three other dwarf planets)  as a planet (many do not)     8 * 8 = 64 planets 

If the number of planets in our solar system were squaered, there would be this number of planets.   

A moving object had been newly discovered in the Solar System as early as 1909 but astronomers had not realized it was an orbiting body.  In 1930, the discovery was recognized as a planet and was named Pluto, at the suggestion of 11-year-old schoolgirl Venetia Burney. 

Pluto remained a planet until the International Astronomical Union decided it didn't conform to their definition of a planet and downgraded it to "dwarf planet" status.  Enough authorities have gone along with that decision to make it stick.  But the IAU is not the boss of me, and I still consider Pluto a planet.  So I say there are still 9 planets, and 9 squared is 81. 

But be aware that, if you submit 81 as your answer, your teacher will mark it incorrect.  For self-preservation, go with 64, as previously answered.  However, I'm obstinate and stand on principle, at least as long as it doesn't cost me too much. 

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