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Name: Unknown
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Date: Prior to 1993

How many known planets are there, inside and outside the solar system? I have read in Astronomy magazine that at least 2 planets were discovered around a pulsar (I do not know where) and that perhaps a 10th planet lies past Pluto. Any more I do not know about?


I have not heard of any good hard evidence for any planets other than the usual nine.

John Hawley

Update - March 2011
As 2011, there are officially eight planets in our Solar System. Pluto, common thought of as the ninth planet, is officially listed as a dwarf planet. There are many dwaft planets in our solar system, Ceres, Pluto, Haumea, Makemake, and Eris.

There have also been planets discovered outside of our solar system, thoughI do not have a count on them at the present time.


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