I actually grew up with nine planets. Yes, I’m that old.
But I’m not old enough to believe that there were just five of them — Mercury, Venus, Mars, Jupiter, and Saturn — orbiting the Earth along with the Sun and Moon. For that kind of old, you have to go to one of my senior companions in the mission field.
Anyhow, though, it now seems that we were right after all. There are nine planets. We were simply mistaken about the name and location of the ninth one.
Fortunately, the poetic folks at Caltech have come up with a really swell name for this new ninth planet:
http://www.sciencedaily.com/releases/2016/01/160120114539.htm
http://www.cnn.com/2016/01/20/us/possible-ninth-planet/