What is an Apparition?
An apparition of a planet is the period during which it is visible, beginning and ending with solar conjunction. In the cases of the inferior planets Mercury and Venus, it is the time between inferior and superior conjunction (morning apparition) and the time between superior and inferior conjunction (evening apparition). Because inferior planets are always near the Sun, they only appear in the east before sunrise and the west after sunset.
Below are a series of diagrams showing the morning and evening apparitions of Mercury and Venus as observed from latitude 10° north. The planet is shown on the 1st, 6th, 11th, 16th, 21st and 26th days of each month with the current year's positions shown in bright white. The path may extend from the previous year or into the next.
Mercury
Mercury undergoes several morning and evening apparitions every year. Morning apparitions occur between inferior conjunction (when the planet is at its dimmest) and superior conjunction (when the planet is at its brightest) whereas evening apparitions always start bright and end with the planet around sixth magnitude. Mercury appears both at dawn and at dusk four times in 2023.
| 21 December | 2022 | greatest elongation east: 20.1° |
| 07 January | 2023 | inferior conjunction |
| 30 January | greatest elongation west: 25.0° | |
| 17 March | superior conjunction | |
| 11 April | greatest elongation east: 19.5° | |
| 01 May | inferior conjunction | |
| 29 May | greatest elongation west: 24.9° | |
| 01 July | superior conjunction | |
| 10 August | greatest elongation east: 27.4° | |
| 06 September | inferior conjunction | |
| 22 September | greatest elongation west: 17.9° | |
| 20 October | superior conjunction | |
| 04 December | greatest elongation east: 21.3° | |
| 22 December | inferior conjunction | |
| 12 January | 2024 | greatest elongation west: 23.5° |
Mercury completes last year's final evening apparition in the first few days of January (blue track), appearing at an altitude of 11.5° before plummeting to the southwestern horizon. The mid-March to April appearance (pink track) reaches the respectable heights of 17.5° but the third evening apparition (green track) is the best one for observers at 10° north latitude. Between July and September, Mercury reaches an altitude of 22.6° in early August when it is also a zero-magnitude object. Mercury reappears in the west in late October (orange track), only to vanish shortly before the end of the year.
Venus
Venus begins the year as the evening star, moving into the morning sky in mid-August.
| 22 October | 2022 | superior conjunction |
| 04 June | 2023 | greatest elongation east: 45.4° |
| 13 August | inferior conjunction | |
| 23 October | greatest elongation west: 46.4° | |
| 04 June | 2024 | superior conjunction |
Venus makes a dramatic appearance after inferior conjunction, make a vertical ascent in the east before levelling off in late October (altitude 44.7°) and gradually declining in altitude thereafter. The morning star is at its brightest at magnitude −4.5 in mid-September.
The evening star is low in the west at the outset of 2023, continuing the final evening apparition of 2022. Beginning at an altitude of just over 16°, it steadily climbs above the horizon as the year progresses, reaching 45.6° in the northwest by early June. Maximum brightness (magnitude −4.5) occurs about a month later. Venus dives toward the horizon from July, disappearing just before inferior conjunction in mid-August.
