Lunar occultation of Neptune

Dominic Ford, Editor
From the Lunar Occultations feed


Objects: Neptune

The Moon will pass in front of Neptune, creating a lunar occultation visible from countries and territories including the western Contiguous United States, north-western Mexico, Hawaii and Midway Atoll amongst others. Although the occultation will only be visible across part of the world – because the Moon is so close to the Earth that its position in the sky varies by as much as two degrees across the world – a close conjunction between the pair will be more widely visible.

Unfortunately the occultation will not be visible from Columbus, though it will be visible from western parts of the Contiguous United States.

The map below shows the visibility of the occultation across the world. Separate contours show where the disappearance of Neptune is visible (shown in red), and where its reappearance is visible (shown in blue). Solid contours show where each event is likely to be visible through binoculars at a reasonable altitude in the sky. Dotted contours indicate where each event occurs above the horizon, but may not be visible due to the sky being too bright or the Moon being very close to the horizon.

Outside the contours, the Moon will not pass in front of Neptune at any time, or is below the horizon at the time of the occultation. However, a close conjunction between the pair will be visible across much of the world.

The map can be downloaded in PNG , PDF or SVG format. A KMZ file , is also available, which can be opened in Google Earth to provide a higher resolution map.

The animation below shows the path of the occultation across the Earth's globe. The red circle shows where the Moon appears in front of Neptune.

[Unable to display this video because your browser does not support HTML5]
You can download this video in MP4 or OGG format.

A complete list of the countries and territories where the occultation will be visible is as follows:

Country Time span
(UTC)
The Contiguous United States 08:49–10:23
Mexico 09:15–10:11
Hawaii 07:19–08:49
Midway Atoll 07:04–08:33
Johnston Atoll 07:10–08:04

Lunar occultations are only ever visible from a small fraction of the Earth's surface. Since the Moon is much closer to the Earth than other celestial objects, its exact position in the sky differs depending on your exact location on Earth due to its large parallax. The position of the Moon as seen from two points on opposite sides of the Earth varies by up to two degrees, or four times the diameter of the full moon.

This means that if the Moon is aligned to pass in front of a particular object for an observer on one side of the Earth, it will appear up to two degrees away from that object on the other side of the Earth.

The position of Neptune at the moment of the occultation will be as follows:

Object Right Ascension Declination Constellation Magnitude Angular Size
Neptune 19h15m30s 21°32'S Sagittarius 7.9 0'02"

The coordinates above are given in J2000.0.

Next/previous occultations

« Previous Next »
Visible from the Contiguous United States Worldwide Worldwide Visible from the Contiguous United States
17 Jun 1992 17 Jun 1992 Occultations of Neptune 10 Aug 1992 28 Jul 1999
17 Jun 1992 10 Jul 1992 Occultations 06 Aug 1992 13 Mar 1993

The sky on 29 Jun 2024

The sky on 29 June 2024
Sunrise
06:03
Sunset
21:04
Twilight ends
23:07
Twilight begins
04:00


Waning Crescent

39%

23 days old

Planets
Rise Culm. Set
Mercury 07:18 14:45 22:13
Venus 06:34 14:03 21:32
Moon 01:27 07:56 14:37
Mars 02:53 09:49 16:45
Jupiter 04:04 11:22 18:40
Saturn 00:40 06:23 12:05
All times shown in EDT.

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

09 Jul 1992  –  Neptune at opposition
27 Sep 1992  –  Neptune ends retrograde motion
22 Apr 1993  –  Neptune enters retrograde motion
11 Jul 1993  –  Neptune at opposition

Image credit

The Moon in conjunction with Venus and Jupiter, with the Very Large Telescope in the foreground. Image © Y. Beletsky, ESO, 2009.

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