Saturn ends retrograde motion

Dominic Ford, Editor
From the Outer Planets feed


Objects: Saturn

Saturn will reach the end of its retrograde motion, ending its westward movement through the constellations and returning to more usual eastward motion instead. This reversal of direction is a phenomenon that all the solar system's outer planets periodically undergo, a few months after they pass opposition.

The retrograde motion is caused by the Earth's own motion around the Sun. As the Earth circles the Sun, our perspective changes, and this causes the apparent positions of objects to move from side-to-side in the sky with a one-year period. This nodding motion is super-imposed on the planet's long-term eastward motion through the constellations.

The diagram below illustrates this. The grey dashed arrow shows the Earth's sight-line to the planet, and the diagram on the right shows the planet's apparently movement across the sky as seen from the Earth:


The retrograde motion of a planet in the outer solar system. Not drawn to scale.

2113 apparition of Saturn

10 Jul 2113 – Saturn enters retrograde motion
02 Sep 2113 – Equinox on Saturn
18 Sep 2113 – Saturn at opposition
18 Sep 2113 – Saturn ring plane crossing
25 Nov 2113 – Saturn ends retrograde motion

Observing Saturn

Saturn leaves retrograde motion as its 2113 apparition comes to an end, although it will remain visible for some weeks in the dusk sky.

Its celestial coordinates as it leaves retrograde motion will be:

Object Right Ascension Declination Constellation Magnitude Angular Size
Saturn 23h29m30s 5°47'S Aquarius 0.8 18.1"

The coordinates above are given in J2000.0.

From Cambridge , it will be visible in the evening sky, becoming accessible around 16:50 (EDT), 34° above your south-eastern horizon, as dusk fades to darkness. It will then reach its highest point in the sky at 18:54, 41° above your southern horizon. It will continue to be observable until around 23:28, when it sinks below 11° above your western horizon.

Over the following weeks, Saturn will reach its highest point in the sky four minutes earlier each night, gradually disappearing into evening twilight.

The sky on 8 May 2024

The sky on 8 May 2024
Sunrise
05:27
Sunset
19:51
Twilight ends
21:46
Twilight begins
03:34


Waxing Crescent

0%

30 days old

Planets
Rise Culm. Set
Mercury 04:38 11:02 17:26
Venus 05:15 12:11 19:08
Moon 05:26 13:06 21:01
Mars 03:52 10:00 16:07
Jupiter 05:55 13:10 20:24
Saturn 03:13 08:51 14:29
All times shown in EDT.

Source

The circumstances of this event were computed using the DE430 planetary ephemeris published by the Jet Propulsion Laboratory (JPL).

This event was automatically generated by searching the ephemeris for planetary alignments which are of interest to amateur astronomers, and the text above was generated based on an estimate of your location.

Related news

25 Nov 2113  –  Saturn ends retrograde motion
21 Jan 2114  –  Saturn ring plane crossing
23 Jul 2114  –  Saturn enters retrograde motion
01 Oct 2114  –  Saturn at opposition

Image credit

© NASA/Cassini

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