Planets
It's a mystery! It all started with an American astronomer named Clyde Tombaugh and our two planets Uranus and Neptune. The year was 1930 (gee that's 69 years ago!), well anyway, back then ole' Clyde was on a hunt to see if he could find out why the orbits (you know what that is right? If not click here) of the planets Uranus and Neptune seemed to be different from all the other planets in our solar system. He spent many years observing the motion of those two planets and wrote down lots of notes, yes, a lot of notes! (Hey, they didn't have computers back then - so he had to write everything down by hand!). OK, so guess what? In all the years he spent looking up at the sky with his telescope, he discovered another planet! Good grief, that makes nine. The new planet was named Pluto.
Well, this was great news to everyone - especially to other astronomers. They had always believed that the different orbits of Uranus and Neptune were caused by a mysterious 'tug' from some undiscovered and until then, undetected planet. Well, since Tombaugh just discovered another planet, everyone thought that was the answer. But as most stories go, it was not.
By the late 1970's (boy, 48 years sure moved along fast) and, now that computers were invented (finally, or you wouldn't be reading this!) lots of astronomers were able to tell that Pluto was just too small to have caused the mysterious 'tug' on the big planets Uranus and Neptune. Hmmmmmmm. So what did? If it wasn't Pluto, then...what was it? The mystery continued.
More scientists got involved. This was really turning into a "planet hunt" and now had been going on for over a half of a century (50 years). It was 1988, just eleven years ago. This time, they were not looking at the ninth planet, Pluto, but instead, they were looking for a tenth planet - Planet X (did you know that in Roman numerals, X means ten? That's why it's called Planet X, it stands for the tenth planet). Clyde Tombaugh wished them luck in their planet hunt. (Remember Clyde? He's the guy that discoverd Pluto in the first place) He was getting older now, he was in his 80's. "They're in for a lot of hard work", he said.
People never give up a quest. Once it's started, it's always finished. If the person that starts a quest is not able to finish it (like Clyde) then the quest is most always taken up by other people that believe in it as well. To find a planet is no easy task. It takes a lot of time; sometimes a lifetime. First, you have to figure out 'where' to look. Then, you have to start looking.
Well, two men, Robert Harrington and Kenneth Seidelmann, took up the quest. They created a make-believe copy of our solar system and added a tenth planet to it. Then they took alot of notes! They made many, many calculations using a computer. Unfortunately, by the end of the 1980's, the computer had run more than a third of a million make-believe copies of our solar system (now that's a lot of copies - 333,000 give or take a few). But, the computer results said that only about 200 were good enough to be real. Wow! Can you image that? They really came up with some real working ideas for a tenth planet in our solar system. So, where is this mysterious Planet X?
They don't know for sure. They do have an idea where it might be located in the sky, though - in the southern sky near the constellation Centaurus.
Astronomers to this day are still looking for Planet X. They truly believe that it passed through our solar system coming very close to the planet Neptune. When this happened, several of Neptune's moons were knocked out of their original orbits as Planet X went by. Astronomers can calculate about how big Planet X would have to be to mess up the orbits of Neptune and Uranus. With that information, they can also tell about how big the orbit of Planet X would have to be. And, with all that information they can also guess as to how long it would take for this mystery planet to orbit the sun. Their guess is that the mysterious Planet X is about two to five times as large as Earth and takes between 350 to 1000 years to orbit the sun just once!
Well, gee - no wonder no one has ever seen it!
So, what do you think?
Is there a Planet X that's part of our solar system?
Maybe you'd like to take up the quest? ...