Should work with Java 7 now :)

Left and Right Arrow to Move. SHIFT to switch between protected and unprotected. You move faster when unprotected, but can't block your planet from incoming planets. When protected (yellow cover above head), hit planets to destroy them. If a planet reaches the center of your planet, the screen will become gray and you will lost. There is a sort of ring in the top-left corner, more will spawn there and some will get stuck in the top-center and the left-middle. Later on, more will spawn near the bottom-right also.

The more you move in one direction, the further the black square by your shield will move away from you. That's what will destroy planets, so remember to move in both directions.

I know worlds and planets aren't the same, the original plan was to have some planets connect and merge with your planet, but I ran out of time.

NOTE - v1.01 is the game as it was originally meant to be although the originally uploaded version is faster/more exciting. The original version is sometimes unbeatable due to planets spawning too fast as I had 2 functions running at
10x the speed so I could test faster. It's your choice which one you want to play.

Some planets will move wildly/extremely fast. That can be
considered a feature - it's planets moving fast and passing your planet instead of hitting it. As for the top and middle, that is the ring or vortex mentioned above.

Sorry if it's bad - didn't have much time to work on it (I'm very young - don't want to say my age though and being my first LD, didn't expect to need as much time as it took).

Made in Java.