At the beginning of any journey, the destination always seems so far away. Taking a road trip, running a marathon, graduating from college, having a baby, all seem so far off and maybe even a bit impossible. Heck you could be trying out something that's never been done before, like going to Mars and that seems impossible.
Everything seems impossible on some level. But don't let that stop you from trying, and taking the steps to do make it happen. You never know what dreams and goals you can actually make happen, and that impossibility you felt before? Hopefully the thing you're left with is a bigger dream to make happen.