Well...rather than launch into a long-winded explanation, here is a little something to get some creative juices flowing.
06:00 High Orbital Research Station Janus 3, Titan, Sol System
The panorama of stars twinkling outside the observation deck's reinforced glass window, completed by the pale turqouise of Titan dominating the lower left of his field of view did little to quell the terror that threatened to engulf him. Nor did the lavish breakfast feast laid upon the long, obsidian conference table in front of him. The lead researcher of the Janus facility couldn't bring himself to even contemplate the eggs, toast, bacon, sausage or hash browns heaped on his plate or the various pastries and fruit set on trays across the table's surface. Brushing a thin hand nervously through his unkempt salt and pepper hair, he glanced at his watch. Where were they? He fumed silently. They needed to see this immediately.
" You needed to see us, doctor?"
The deep timbre of the voice behind him, as well as the complete lack of warning, startled the doctor to his feet, sent him almost sprawling to the floor were it not for the quick reflexes and steady hand of the speaker.
" Y-yes...Colonel. We have a problem. One that the rest of the crew can't know yet..."
The Colonel, his weathered face concerned and wary, turned to his aide, a young blonde of austere features wearing a crisply tailored lieutenant's uniform, nodding silently. The slim woman turned wordlessly, fingering a small numeric keypad by the chamber's entrance, sealing it from intrusion. Turning his bald head back to the doctor, he gently pulled the man to his feet with a smile.
" What is this about, doc? I'm not in the habit of hiding things from my men."
Visibly shaken, the doctor silently removed a small black rectangular box from the pocket of his white lab coat, setting it on the table in front of him.
" Three hours ago, we received a coded distress beacon from the mining ship, Baleforge. It was assigned to the Kuiper Belt but also doubled as a supply ship for us and several military ships in this sector. There was no audio on the transmission...just a scan from the baleforge's systems. Chiefly this..."
He pressed a small depression on the box and the three beams of irridescent lights shot forth, criss-crossing several times as they formed an image. A spherical ship, surrounded by millions of smaller vessels.
" The sphere is massive, nearly two thirds the mass of Earth. Even the smaller ones dwarf anything in the Confederation's arsenal save the Starcarrier Class. According to sweeps of our own scans this morning, this fleet has wiped out any and all settlements and ships between here and the far side of Pluto..."
The Colonel's brow furrowed as he stared at the 3D rendering.
"How did it slip past our defenses?"
"it didn't. From what little I can gather, it fired some sort of long range precision energy weapon from outside the Belt before entering. Used it to clear a hole big enough to pass through without having to navigate any asteroid fields."
" You mean to tell me these things blew away eight million of our people from outside Sol system?!"
The fear in the colonel's voice was naked and the lieutenant's blue eyes were wet with tears.
" And they're still coming.....to kill us all presumably..."