I have just learned that all objects with mass attract eachother. So if I took the example of an apple falling out a tree. The apple is under the earths gravitational force, but the earth is also under some gravitational force from the apple though this force is far less. My question is why? Why does anything with mass have it's own gravitational field? I know that the earth and other planets orbit the sun and that it is to do with again a gravitational pull, or atleast that is what I think, but why is this? I have an image below that I have seen alot when talking about gravitational fields, but I am struggling to interperate it, questions like why do the planets not just get drawn straight towards to sun? If you have an links to information or anything that may help I would most appreciate it. My question might have a very simple answer, but it is one that I haven't found.