Lunar occultation of Regulus

Dominic Ford, Editor
From the Lunar Occultations feed


Objects: Regulus

The Moon will pass in front of Regulus (Alpha Leonis), creating a lunar occultation visible from Africa and Western Asia. 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.

The occultation will be visible from Fairfield. It will begin with the disappearance of Regulus (Alpha Leonis) behind the Moon at 11:04 EDT, though in daylight and at a low altitude of only 2.5 degrees, in the eastern sky. Its reappearance will be visible at 11:48 EDT, though in daylight and at a low altitude of 10.7 degrees.

Extreme caution is necessary when pointing binoculars or telescopes at the sky when the Sun is above the horizon, as even a momentary glance at the Sun through such an instrument can cause permanent blindness.

The map below shows the visibility of the occultation across the world. Separate contours show where the disappearance of Regulus (Alpha Leonis) 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 Regulus (Alpha Leonis) 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.

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

Country Time span
(UTC)
Sudan 17:14–18:59
Saudi Arabia 17:21–18:45
Chad 17:05–18:41
Ethiopia 17:41–19:02
Egypt 17:03–18:31
Democratic Republic of the Congo 17:52–18:57
Tanzania 18:09–19:03
Somalia 17:51–19:05
Central African Republic 17:35–18:51
Kenya 17:56–19:05
Yemen 17:45–18:51
Libya 17:02–18:30
Oman 17:53–18:41
Iraq 17:28–18:08
Uganda 17:57–19:00
Syria 17:19–18:04
Cameroon 17:27–18:28
Eritrea 17:38–18:51
Jordan 17:20–18:13
United Arab Emirates 17:53–18:24
Nigeria 17:24–18:26
Burundi 18:14–18:54
Israel 17:18–18:13
Rwanda 18:10–18:55
Republic of the Congo 18:01–18:32
Djibouti 17:50–18:53
Madagascar 18:34–19:01
Kuwait 17:46–18:07
Qatar 17:52–18:20
Niger 17:12–18:23
Lebanon 17:19–18:02
Palestinian Territory 17:18–18:07
Mozambique 18:39–18:53
Seychelles 18:16–19:08
Bahrain 17:52–18:15
Comoros 18:41–18:54
Mayotte 18:46–18:51

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.

At the time of the occultation, the Moon will be 6 days past new moon and will be 32% illuminated. Regulus (Alpha Leonis) will disappear behind the unilluminated side of the Moon and reappear from behind the illuminated side of the Moon.

The position of Regulus (Alpha Leonis) at the moment of the occultation will be as follows:

Object Right Ascension Declination Constellation Magnitude Angular Size
Regulus (Alpha Leonis) 10h08m20s 11°58'N Leo 1.4 0'00"

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
20 Apr 2100 17 May 2100 Occultations of Regulus (Alpha Leonis) 10 Jul 2100 28 Oct 2100
20 Apr 2100 26 May 2100 Occultations 20 Jun 2100 10 Jul 2100

The sky on 23 Jul 2024

The sky on 23 July 2024
Sunrise
05:37
Sunset
20:17
Twilight ends
22:14
Twilight begins
03:40


Waning Gibbous

91%

18 days old

Planets
Rise Culm. Set
Mercury 08:00 14:43 21:25
Venus 06:45 13:54 21:03
Moon 21:35 02:43 08:00
Mars 01:27 08:44 16:01
Jupiter 02:06 09:30 16:54
Saturn 22:27 04:08 09:48
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.

Image credit

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

Share