Star System P-46892 (Aiken), Outer System Reaches, Terran Year 2852
The pulse came from an area about sixteen light-minutes, somewhere around 2 AU, away from the star, just inside the orbit of the system's innermost planet, not so lovingly dubbed Avarice because of it's thin atmosphere and frequent earthquakes. This was a young system, so even though the planets were small, they were still very active.
This invisible radiation spike grew in intensity, continuing until the radiation had shifted into the electromagnetic spectrum, and then leaked into the visible light range It started as a soft glow against the dotted black backdrop of space