08/29/2026
Observing Project:
Retrograde Motion of Saturn
Over the next six months, observe ringed Saturn using binoculars,
then plot its changing position among the background stars.
Saturn can be found southeast of the Great Square, fours stars of nearly the same brightness as those of the Big Dipper. In early evenings in September and early October, the Great Square – and Saturn – rise higher at the same time each evening in the east. In November, and December, Saturn climbs to its highest in the south, while in January and February, it drops closer to the western horizon.
During this period, the planet first will move westward (i.e., retrograde) until mid December, then eastward (i.e., prograde). This area is bounded by the faint stars 96 and 44 Piscium, and 20 and 14 Ceti. During most of this time, Saturn lies in Cetus – not a zodiacal constellation – and not in Pisces.
Activity
1. Find Saturn in binoculars. Plot it and the brighter background stars. Include 14 Ceti (5.93 mag.), 20 Ceti (4.75 mag.), 44 Piscium (5.75 mag.), and 96 Piscium (5.71 mag.).
2. Every 10 – 14 days plot Saturn again, judging its location from those four background stars.
3. Continue through February.
4. Saturn will stop moving westward on Dec 11.
5. On about March 1, the planet will be near the same spot in the sky as it was on Sep 1.
Why do this activity? This planetary dance can only be explained if both Earth and Saturn orbit our sun following slightly elliptical paths. Our view from Earth clearly shows this to those people who take the time to look carefully enough.
