"I love my planet"

[slashmel.livejournal.com]

Today at work, a girl was wearing a t-shirt with the same phrase written in several languages. I usually pay no attention to my coworkers, but I noticed Russian characters on the tee and decided to take a closer look.

"Я люблю мою планету" was painted on the fabric and I was sure there was something about it: Is it планета? So, I checked on my books when I got home and I found мой, моя and моë but never мою. Does it really exist? In which cases is it used?

It's such a dumb question I know, but it just intrigued me...