Jupiter ends retrograde motion

Dominic Ford, Editor
From the Outer Planets feed


Objects: Jupiter

Jupiter 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.

1962 apparition of Jupiter

02 Jul 1962 – Jupiter enters retrograde motion
31 Aug 1962 – Jupiter at perigee
31 Aug 1962 – Jupiter at opposition
29 Oct 1962 – Jupiter ends retrograde motion

Observing Jupiter

Jupiter leaves retrograde motion as its 1962 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
Jupiter 22h22m50s 11°29'S Aquarius -2.6 43.3"

The coordinates above are given in J2000.0.

From Los Angeles , it will be visible in the evening sky, becoming accessible around 17:21 (PDT), 33° above your south-eastern horizon, as dusk fades to darkness. It will then reach its highest point in the sky at 19:44, 44° above your southern horizon. It will continue to be observable until around 00:32, when it sinks below 7° above your western horizon.

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

The sky on 28 Jun 2024

The sky on 28 June 2024
Sunrise
05:41
Sunset
20:08
Twilight ends
21:52
Twilight begins
03:56


Waning Crescent

42%

22 days old

Planets
Rise Culm. Set
Mercury 06:52 14:03 21:14
Venus 06:11 13:23 20:35
Moon 00:26 06:34 12:52
Mars 02:26 09:11 15:56
Jupiter 03:43 10:46 17:49
Saturn 00:01 05:47 11:33
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

29 Oct 1962  –  Jupiter ends retrograde motion
09 Aug 1963  –  Jupiter enters retrograde motion
08 Oct 1963  –  Jupiter at opposition
05 Dec 1963  –  Jupiter ends retrograde motion

Image credit

© NASA/Cassini

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