I once had a pet planet

I once had a pet planet. I kept it in a cage and named it Earth.
It was round and cute, blue and green with swirly white fluff that changed all the time.
Sometimes watching it keeps me entertained.
I poke it when I get bored.  I know I shouldn't, but I don't like being bored.
Then things get interesting.
The blue bits ripple and lap against the green bits, sometimes washing over them,
The white fluff swirls into pretty whirlpools that float across the blue and green,
bits of ice at the top and bottom break away, and sometimes some of the mountain-tops will glow red-orange while the green shakes.
It's pretty at night, too - parts of the green glow with little tiny specks of light. Well, they disappear for a while after I poke my planet, but eventually the glow comes back. It always comes back.
But one day I poked my planet too hard. The white swirled faster, lots of little mountain tops glowed red, the blue swamped the green, which shivered as bits broke off and sank. Vanishing into the blue.
The lights didn't come back this time, and the green turned brown, and the blue evaporated away.
The next day my planet was dead.
I felt sad, and a little worried, but my parents say that if I'm good I'll get another planet for Christmas. I wonder what I'll name it?