Our solar system technically reaches far beyond what we consider the “four basic food groups,” most often referenced: inner planets (rocky), asteroid belt, outer planets (gas/ice), and Kuiper Belt. Past the frozen region of icy bodies in the Kuiper Belt, the most famous of which is perhaps the dwarf planet, Pluto, is the heliosphere stretching out another nine billion miles. Voyager 1 is the only man-made craft to pass through this far-reaching distance of the Sun’s influence. Yet, at Voyager 1’s current speed and having already traveled nearly 49 years, it will take about 300 more years to reach the inner edge of the Oort Cloud.

So astonishingly remote, our present technology has not yet imaged the Oort Cloud. Searching for the source of comets, long range and short range, led to theories of this vast reservoir of ice planetesimals beyond the Kuiper Belt. Dutch astronomer Jan Oort is credited for reviving, Estonian astronomer, Ernst Opick’s proposal that long interval comets in highly elliptical orbits were permanent members of the solar system. Possibly trillions of these objects exist at the solar system perimeter, and every now and then, plummet towards the Sun. Comet brightness is wildly variable and famously difficult to predict. A long-range comet may enter our evening skies once in a lifetime or never be seen again in the timeline of humanity.