Great conjunction - Wikipedia
https://en.wikipedia.org/wiki/Great_conjunctionOn average, great conjunction seasons occur once every 19.859 Julian years (each of which is 365.25 days). This number can be calculated by the synodic period formula in which J and S are the orbital periods of Jupiter (4332.59 days) and Saturn (10759.22 days), respectively. This is about 52 days less than 20 years, but i…
The ‘Great’ Conjunction of Jupiter and Saturn | NASA
www.nasa.gov › feature › the-great-conjunction-ofDec 15, 2020 · Saturn, top, and Jupiter, below, are seen after sunset from Shenandoah National Park, Sunday, Dec. 13, 2020, in Luray, Virginia. The two planets are drawing closer to each other in the sky as they head towards a “great conjunction” on December 21, where the two giant planets will appear a tenth of a degree apart. Credits: NASA/ Bill Ingalls