If there is, it's a secret.
You've essentially just asked "is there a known planet no one knows about". The answer should be self-evident. The chances that the IAU could keep a planet a secret from everyone else are, essentially, zero.
Pluto is the planet that scientist are saying is not a planet. Scientists are not saying any particular planet is not a planet. Simply that Pluto has been reclassified as a dwarf planet.
No, Jupiter is the largest planet in the solar system.
Planet X was a hypothetical planet which was searched for after the discovery of planet Neptune. `Planet-X` does not exist.
Pulto is a hypothetical planet sometimes referred to in science fiction or urban legends, but it is not officially recognized as a planet or dwarf planet by the scientific community.
Oh, dude, the secret code for turtle knock in Lictrecy Planet is obviously... wait for it... 8675309! Just kidding, I have no idea what that is. But hey, if you figure it out, let me know so I can finally unlock the mystical world of turtle knocking on Lictrecy Planet.
silver savage
literacy planet secret code:redredred ghost jellypus penpen
Star Blazers - 1979 The Secret of Planet Guardiana 3-24 is rated/received certificates of: Australia:G
15th of novenber
u stink
I only know the (#) one it i will be a sun smiley
John Carter
Ask Google
the alien comes from another planet(Mars) in search of a secret location on Earth
YES! Anyone with a month old account can be a secret agent. So if you pass the test (which is the easiest test on the planet) you will receive a spy phone.
Well, honey, I don't have the secret code for turtle knock on Literacy Planet. You might want to try reaching out to their customer support for that kind of information. Good luck cracking the code, Sherlock!