Jupiter enters retrograde motion

Dominic Ford, Editor
From the Outer Planets feed


Objects: Jupiter

Jupiter will enter retrograde motion, halting its usual eastward movement through the constellations, and turning to move westwards instead. This reversal of direction is a phenomenon that all the solar system's outer planets periodically undergo, a few months before they reach 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.

2034 apparition of Jupiter

02 Aug 2034 – Jupiter enters retrograde motion
01 Oct 2034 – Jupiter at perigee
01 Oct 2034 – Jupiter at opposition
28 Nov 2034 – Jupiter ends retrograde motion

Observing Jupiter

Jupiter enters retrograde motion as its 2034 apparition gets underway, although it has already been visible for some weeks in the pre-dawn sky.

Its celestial coordinates as it enters retrograde motion will be:

Object Right Ascension Declination Constellation Magnitude Angular Size
Jupiter 00h51m40s 3°58'N Pisces -2.7 43.7"

The coordinates above are given in J2000.0.

From Cambridge , it will be visible in the morning sky, becoming accessible around 23:20, when it reaches an altitude of 7° above your eastern horizon. It will then reach its highest point in the sky at 04:52, 51° above your southern horizon. It will be lost to dawn twilight around 05:15, 51° above your southern horizon.

Over the following weeks, Jupiter will reach its highest point in the sky four minutes earlier each night, gradually becoming visible in the evening sky, as well as the pre-dawn sky, as it approaches opposition.

The sky on 2 Aug 2034

The sky on 2 August 2034
Sunrise
05:34
Sunset
20:02
Twilight ends
21:57
Twilight begins
03:38


Waning Gibbous

86%

18 days old

Planets
Rise Culm. Set
Mercury 05:22 12:42 20:02
Venus 09:32 15:41 21:50
Moon 20:51 02:23 08:03
Mars 06:01 13:11 20:21
Jupiter 22:34 04:52 11:09
Saturn 04:28 11:53 19:18
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

02 Aug 2034  –  Jupiter enters retrograde motion
01 Oct 2034  –  Jupiter at opposition
28 Nov 2034  –  Jupiter ends retrograde motion
09 Sep 2035  –  Jupiter enters retrograde motion

Image credit

© NASA/Cassini

Share