1952 Daily UFO HistogramAfter a minor peak in late April, UFO activity peaked in mid to late July 1952; The heaviest wave in US history.
The peak days were July 28, 23, 26 and 29 in that order, with as many as 19 reports listed on the 28th.
Out of 1073 sightings worldwide, the USA has 761 listed, Canada 47, South America 13, plus 111 in Europe. None of those came from Eastern Europe, just a wall of silence.
*U* also lists 10 events in Australia, and 15 in New Zealand. Another 46 reports from Asia are mainly military, 17 from Japan alone. 45 reports also come from the northern and southern extremes of Africa.