Uranus ends retrograde motion

Dominic Ford, Editor
From the Outer Planets feed


Objects: Uranus

2128–2129 apparition of Uranus

02 Dec 2128 – Uranus enters retrograde motion
14 Feb 2129 – Uranus at opposition
30 Apr 2129 – Uranus ends retrograde motion

Uranus 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.

This motion was known to ancient observers, and it troubled them as they could not reconcile it with models in which the planets moved in uniform circular orbits around the Earth, as they believed.

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.

Observing Uranus

Uranus leaves retrograde motion as its 2128–2129 apparition comes to an end, although it will remain visible for some weeks in the dusk sky.

As retrograde motion ends, it will become visible at around 20:31 (PDT), 69° above your south-western horizon, as dusk fades to darkness. It will then sink towards the horizon, setting at 02:38.

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

As it leaves retrograde motion, its celestial coordinates will be:

Object Right Ascension Declination Constellation Magnitude Angular Size
Uranus 09h38m50s 14°50'N Leo 5.4 3.9"

The coordinates above are given in J2000.0.

The sky on 25 Apr 2026

The sky on 25 April 2026
Sunrise
06:07
Sunset
19:30
Twilight ends
21:01
Twilight begins
04:36


Waxing Gibbous

76%

9 days old

Planets
Rise Culm. Set
Mercury 05:26 11:40 17:54
Venus 07:30 14:33 21:37
Moon 14:04 20:48 03:24
Mars 05:09 11:22 17:35
Jupiter 10:45 17:53 01:02
Saturn 05:04 11:10 17:16
All times shown in PDT.

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

30 Apr 2129  –  Uranus ends retrograde motion
07 Dec 2129  –  Uranus enters retrograde motion
19 Feb 2130  –  Uranus at opposition
06 May 2130  –  Uranus ends retrograde motion

Image credit

© NASA/Voyager 2

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