On the New Frontier...Falling Away

(This is the first totally new story I have written in a good while. It is a very short story, but uses science fiction to tell a tale of making sure history ends in a place. And of course, there is a small amount of mystery to go with the story.)

I stared at the stars, searching for an answer.
None presented themselves for review, so I found myself staring across the horizon. Looking to the west, I saw the faintest of glows. I sighed at it, knowing the twin moons were about to rise.
I sat, wearily upon the rock nearest to me. I kept staring towards the faint moonrise, one thought going through my mind. It kept cycling continuously, akin to drums I had once heard on the plains of Africa so many years ago. Haunting was that melody, as tireless as the Darkness.
It has come to this. It has come to this. It has come to this.
I looked into the darkness of the east, hearing those words and those drums of days past. I smiled sadly, my entire life playing out in my head. so many adventures spread across the vastness of time itself. So many places, and so many dreams chasing each other.
It has come to this. It has come to this. It has come to this.
The rebel and independent spirit in me suddenly gripped me. I felt the urge to run, as I had always done. Find another way, search for the possibilities, luck into a solution and all the like.
Shaking my head, I sat once again on the rock. My momentary surge of rebelliousness caused me pain and weakness. I fought off a shudder, knowing that my cellular degeneration was fighting the chemicals in myself and my will to perform one last time upon the stage of existence.
It has come to this. It has come to this. It has come to this.
"Ah Roderick, cells turning to jelly on you?"
I didn't even turn at the sound of the cold mockery. "You should know very well the answer to that."
A low sinister laugh washed over me. I refused to turn still, knowing full well the expression on the face of my companion of the moment. Hearing his laughter subside, I spoke evenly, "Have you decided on my offer?"
"Indeed I have, "came the scornful reply," and find your offer laughable and almost contemptible."
I shook my head sadly and slowly. Knowing he would answer that way still made this difficult. I pushed myself painfully off my rock, pulling my ancient Terran pocket watch out. Pushing the release open, I noted the time with fondness. Closing the watch, I turned to face my companion.
I looked into the familiar features and burning eyes. Even in this darkest of moments, I could not resist a faint smile. I always found the sight of my companion just slightly amusing.
Staring at my own features without the benefit of a mirror, I noted the sneer on my double's face. No sense of humor in my alternate dimension self as usual, smiling back at him.
My alternate self drew his weapon. Smiling wickedly, I watched him make a dramatic show of setting the thing to full intensity. I could not help myself, I smiled watching my very own sense of high drama play out in front of me. I held my hands out in front of me, smiling broader now.
"I am glad to see that our sense of drama is still quite intact after all."
My double merely continued to train his weapon on me. His sense, like mine, no doubt detected the menace in my studied nonchalance. He studied me intently, looking for a clue to my calm in the face of death.
I moved slightly, putting my back to the increasing moonrise. Staring intently at each other, a sudden wind whipped up. I smiled brightly, gritting my teeth through the pain of cellular degeneration. I watched slowly as a sudden realisation spread across my face mirrored opposite of me.
My double tapped away at the communicator on his wrist. He tapped harder and harder as he received no satisfactory response. His eyes widening in panic, he kept trying. Finally he ripped off the device and held it in his hand. Hissing at me, he spat, "Cute Roderick. However the ultimate victory will be mine."
I merely smiled as he pressed a button on his communicator. I knew damn full well what it was for. It was the fail safe arm for his plague bombs set across the galaxy. Once activated, 90% of the galaxy's population would die slowly, agonizingly. What would be left would be unable to fight off the alternate dimension's forces, allowing them dominion over an entire galaxy.
The darkness wavered around us. I simply stood, watching in amusement. I finally said, "Rod my boy, you would dream for a moment that I would let you just carry the day, would you?"
My doppelganger glared at me, then at the sky. Clouds formed suddenly and skated in rapid pace across the sky. Lightning flashed in those clouds, growing in intensity. Laughing loudly, I spread my arms. Screaming above the madness of nature, I starred deep into Rod's eyes.
"I had a terrible time finding a place to bring you. Knowing your history matched mine nearly to the letter, and knowing you so intimately, I knew you weren't going to fall for a clever trick."
I paused long enough to glare at Rod. Discerning the panic in his eyes, I laughed as loud as I could. I continued screaming, as the ground commenced heaving.
"So it has come to this! Your ships is gone! We stand together, dying. Your plan is ruined! It has come to this!"

In orbit of the Pralis nebula, a marker makes it's passage every year. It beeps out a simple message.
Here ended the day...beginning the day anew.