Neptune's 164.9-year orbit around the Sun will carry it to its closest point to the Sun – its perihelion – at a distance of 29.81 AU.
In practice, however, Neptune's orbit is very close to circular; its distance from the Sun only varies by about 1.7% between perihelion and aphelion. This means that the difference in the amount of heat and light it receives from the Sun between aphelion and perihelion is extremely small.
Finding Neptune
Neptune's distance from the Sun doesn't affect its appearance. From Fairfield, at the moment of perihelion it will be visible in the morning sky, becoming accessible around 23:02, when it reaches an altitude of 21° above your eastern horizon. It will then reach its highest point in the sky at 03:50, 61° above your southern horizon. It will be lost to dawn twilight around 05:22, 55° above your south-western horizon.
A chart of the path of Neptune across the sky in 2042 can be found here, and a chart of its rising and setting times here.
The position of Neptune at the moment it passes perihelion will be:
| Object | Right Ascension | Declination | Constellation | Magnitude | Angular Size |
| Neptune | 02h30m40s | 12°56'N | Aries | 7.8 | 2.3" |
The coordinates above are given in J2000.0.
The sky on 28 Sep 2024
| The sky on 28 September 2024 | ||||||||||||||||||||||||||||||||||
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8% 25 days old |
All times shown in EDT.
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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
| 13 Aug 2042 | – Neptune enters retrograde motion |
| 01 Nov 2042 | – Neptune at opposition |
| 17 Jan 2043 | – Neptune ends retrograde motion |
| 15 Aug 2043 | – Neptune enters retrograde motion |
Image credit
© NASA/Voyager 2