Planet Designation Generator

So there was a request that we create a little web thingie that will automatically generate planet designations for the Stargate universe. We took up the challenge and came up with our very own Exalted Planet Designation Generator. These are our notes:

• We studied the Wikipedia page that lists Stargate planets to identify patterns in the naming schema. This is what we found:
  
  
• For Milky Way galaxy designations:
• Six-character planet designations are by far the norm (90% of the time), however there have also been 5 seven-character designations and 3 five-letter designations. Our generator currently only creates six-character designations. The next version/release of our generator will produce five- and seven-letter designations in the proportion that they exist in canon.
• The first character for is either P (if the world is a planet) or an M (if the world is a moon). That said, there have been two planets in canon that didn't fit this convention. BP6-3Q1 was the planet from "Bane", with the giant bugs that infested Teal'c and KS7-535 was the frozen planet from "Lockdown", where Carter sent Anubis (in Vaselov's body). We have decided that non P- and M- worlds are those that have been classified as posing undue risk to SGC personnel. Our generator does not currently create designations that are unsafe for human life, but that option will be available in the next version/release.
• The second character is a number 91% of the time, but never a zero. Nor are the letters I or O used.
• The third character is a number only 14% of the time. Also, that character is either the letter X or C 47% or 8% of the time, respectively. No vowels other than A are ever used.
• The fourth and sixth characters are always numbers, using all values (including zero).
• The fifth character is a number 96% of the time, using all values (including zero).
  
  
• For Pegasus galaxy designations: As of the last check of the Wikipedia page, there were only 30 designations from canon - less than half from the Milky Way. As such, a detailed analysis of patterns is bound to be less reliable than if there were more data to study. Nevertheless...
• Pegasus galaxy designations are always six characters long.
• The first character for is either M (if the world is a moon) or P (if the world is a planet). 90% of the worlds visited were moons. In one instance (for the planet Lantea), the first three characters were "ATL". However, that code was assigned from Earth - probably to distinguish it from all the planets in the Milky Way. All worlds with designations assigned from Pegasus fit the moon/planet convention.
• The second, fourth, fifth, and sixth characters are always numbers, not including zero.
• The third character is a number 13% of the time, but never a zero, an I, or an O.
  
  
• All that figured out, we created a PHP script (from scratch! yay us!) that would generate planet designations that meet the above criteria while at the same time automatically reject any that were already listed on the Wikipedia page.

If you have any comments, suggestions, or find any problems with our logic and/or our generator, please let us know. Otherwise, now is a good time for you to applaud our greatness.