There seemed to be a mystifying universal conspiracy among textbook authors to make certain the material they dealt with never strayed to near the realm of the mildly interesting and was always at at least a long-distance phone call from the frankly interesting.
Incidentally, disturbance from cosmic background radiation is something we have all experienced. Tune your television to any channel it doesn't receive, and about 1 percent of the dancing static you see is accounted for by this ancient remnant of the Big Bang. The next time you complain that there is nothing on, remember that you can always watch the birth of the universe.
Of course, it is possible that alien beings travel billions of miles to amuse themselves planting crop circles in Wiltshire or frightening the daylights out of some poor guy in a pickup truck on a lonely road in Arizona (they must have teenagers, after all), but it does seem unlikely.