399-Day Mean Synodic Period of Jupiter Jupiter’s mean synodic period repeats after slightly less than 399-days. A synodic period completes when an observer sees the celestial sky return to the previous state. Jupiter moves into each of 12 constellations approximately every 34-days. Our own faster 365.25-day revolution about the sun overtakes Jupiter by slightly more than a month year after year.
Cart Item 399DMSPJ 103 kb