On March 14, Jupiter and Uranus will be at heliocentric conjunction – that is, in the same direction as seen from the Sun – for the first time since 1941 April 21, just under 83 years ago.
In this view from 15 degrees north of the ecliptic plane, and from ecliptic longitude 228, the paths of the planets are shown in March, and sightlines from Earth to Uranus and from the Sun to Uranus at March 14. The Sun is exaggerated 4 times in size, the four inner planets 300 times, the giant outer planets 50 times. The dashed line is toward the vernal equinox direction, the zero point for mapping positions in the sky.
As seen from Earth, they are not far “left” (east) of the Sun, in the evening sky, and the conjunction does not happen till April 21, when brilliant Jupiter (magnitude -2) will appear half a degree south of dim Uranus (magnitude 5.8, barely within the naked-eye limit). You can see Jupiter’s progress toward Uranus in our evening sky scene of a couple of days ago.
As Astronomical Calendar 2024 explains on page 118 under the large diagram of the wider solar system, “The four giant planets are still in one quadrant of the sky, starting in the order Saturn-Neptune-Jupiter-Uranus, but Jupiter overtakes Uranus this year, so that the angular span begins to widen; by the year’s end it will be 89°.”
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13 years, more or less?
I think April 21 1941 may be a typo. https://articles.adsabs.harvard.edu//full/2003JRASC..97..173D/0000174.000.html .. As that would be an opposition of Uranus from Jupiter which would happen somewhere on each revolution of Jupiter ie. a Jupiter year. Unless I am not following this correctly
Jupiter orbits the Sun every 12 years. Uranus takes 84 years to orbit the Sun. So Jupiter passes Uranus every 14 years or so, 12 years to get back to where Jupiter was one cycle ago, and another two years to catch up to how far Uranus has traveled since their last meeting. My geocentric ephemeris shows Jupiter conjunct Uranus in 2010 June and September, and 2011 January. The rhythm of three conjunctions was due to Jupiter traveling direct, then retrograde, then direct again, as seen from Earth. I can’t find a date for the heliocentric conjunction, but it would have been during that same time frame.
The 1941 Jupiter-Uranus conjunction was one Uranus orbit ago, within four degrees of geocentric ecliptic longitude of the 2024 conjunction.
Jupiter orbits over 30.3 degrees per year on average, Uranus averages only c. 4.29 for a net of >26, it wouldn’t take almost a whole Uranus orbit.