(my idea)
As your character wonders the wastes, he gets a call from Jason Bright. He tells you that him and his ghoul followers made the great journey safe and sound. Sadly he says that he forgot something very important back at the Mojave waste land. Your quest marker tells you that you need to go back Recon test site. You go back there and have to retrieve the thing that Jason Blight wants (I don't know what it is but I think you can figure out something). After retrieving it, you go to the control room to talk to Jason Bright on a long way intercom. He tells you to bring it with you and to keep it safe. He tells you that there is a an extra one man rocket to head to the great journey. You get in with the important thing. Sadly since its a one person rocket you cannot bring any companions. Also because of the weight factor you can only bring 50 pounds of weight/weapons/armor etc. You blast off. You watch the Mojave waste turn to a spec. It says 3 days later or what ever.
***
You land on the moon. You explore the moon and notice a few ghoul and Enclave bodies. After about 5 minutes of wandering, you see the ghoul town. The ghouls greet you and idolize you. You see Jason Bright. You noticed the town is still in construction. You see that most of the ghouls are heavily armed. Jason takes the important item from you. He thanks you very much and says that you may leave. As you are returning to the pod you blasted by… a huge explosion.
***
You wake up in a Enclave hospital. You see that they have also made a town/base. You see ships shipping supplies back and forth from earth (capital wasteland). You are greeted by a man named Howard Ratliff. You see by his suit that he is a Enclave General. He tells you that the Enclave was trying to bomb the ghouls town but missed and hit you. He asks you why you were up on the moon. You have dialogue options. Howard tells you that the Enclave came to the moon because they want to put up satellites and make a space station. He tells you that President Eden (he's still alive since its 10 years before fallout 3) wants to cleanse every mutated/radiated creatures on earth. Howard says that he does not want the ghouls to expand not even on the moon. He takes off your chains. He lets you go. At this point you can ether ask him if he needs any help and then you can join the Enclave and try to defeat the ghouls, or you can simply leave and report back to the ghouls.
You guys can figure out the rest
