A,D Keys: Turn the digger left or right. You'll want to avoid the white rock objects, they subtract from your hull. There are also other objects which eat up fuel. Remember you're trying to go as deep as possible.
Your ship has crashed and you're out of fuel! How will you ever make it off of this dirtball planet? Well, if you manage your resources properly and harness the power of your working technology you just might be able to drill to the center of the planet and scrounge up increments of the elements you'll need in order to repair your hull and fuel your ship! It'll be hard work for sure, but at least it's honest! Navigate your drill farther and farther into the depths of the planet. Avoid rocks and mines. Collect various elements to upgrade your ship so you can power up your hull, fuel, shields, and other aspects of your machine. Your survival depends on your ability to successfully worm your way through this distant earth.