Solar System Phenomena — Selected Minor Planets at Opposition in 2023

Positions of selected minor planets at opposition in 2023

The chart shows the positions selected minor planets at the instants of their oppositions in ecliptic longitude. All of these objects have relatively large inclinations and may stray far from the ecliptic (which is marked on the chart). For this reason, the dates of opposition (or conjunction) in right ascension may differ by several days from the dates listed below. Similarly, the date of greatest angular elongation from the Sun may also fail to coincide with the date of opposition in ecliptic longitude.

Only 4 Vesta has the potential to reach naked-eye visibility but the other large asteroids — 1 Ceres, 2 Pallas and 3 Juno — are visible in small- to medium-sized telescopes. The trans-Neptunian dwarf planets require large telescopes and detailed finder charts, and with the possible of exception of 134340 Pluto, are probably beyond the reach of amateur astronomers.

DateMinor PlanetEventApparent Magnitude
08 January 2 Pallas opposition in Canis Major +7.7
18 January 134340 Pluto conjunction
21 March 1 Ceres opposition in Coma Berenices +7.0
29 March 136472 Makemake opposition in Coma Berenices +17.2
15 April 136199 Eris conjunction
20 April 136108 Haumea opposition in Boötes +17.3
24 April 4 Vesta conjunction
20 June 3 Juno conjunction
22 July 134340 Pluto opposition in Sagittarius +15.0
01 October 2 Pallas conjunction
02 October 136472 Makemake conjunction
19 October 136199 Eris opposition in Cetus +18.7
24 October 136108 Haumea conjunction
20 November 1 Ceres conjunction
21 December 4 Vesta opposition in Orion +6.2


Minor planet positions at opposition are provided by the Minor Planet Center. Magnitudes are approximate.