In the approximate year of 7 B.C., the orbits of Jupiter and Saturn brought them into very close proximity to one another in the constellation of Pisces. Their position relative to the sun, which is their opposition, provided the optimum angle for the maximum reflection of sunlight back to the earth.
From May to December of that year, the two planets passed each other three times, which is a triple conjunction. During all of these passes, the planets appeared to merge to occupy virtually the same virtual space, which is called an occultation. Occultation effectively combines the reflected light intensity of the two planets as if they were one. This very specific, extremely rare type of planet conjunction has only occurred once in all of the recorded history that we currently have, and will occur again theoretically approximately 5,000 years from now.