Lunar occultation of Spica

Dominic Ford, Editor
From the Lunar Occultations feed


Objects: Spica

The Moon will pass in front of Spica (Alpha Virginis), creating a lunar occultation visible from countries and territories including western Western Sahara, western Mauritania, western Senegal and the Canary Islands 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.

The occultation will be visible from Fairfield. It will begin with the disappearance of Spica (Alpha Virginis) behind the Moon at 15:23 EDT, though in daylight. Its reappearance will be visible at 16:28 EDT, though in daylight.

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 Spica (Alpha Virginis) 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 Spica (Alpha Virginis) 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)
Western Sahara 20:56–21:59
Mauritania 21:04–22:00
Senegal 21:14–22:02
The Canary Islands 20:49–21:52
Cape Verde 21:06–22:02
The Portuguese Azores 20:24–21:30
Gambia 21:21–22:02
Madeira 20:43–21:44
The Savage Islands 20:49–21:47

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 17% illuminated. Spica (Alpha Virginis) will disappear behind the unilluminated side of the Moon and reappear from behind the illuminated side of the Moon.

The position of Spica (Alpha Virginis) at the moment of the occultation will be as follows:

Object Right Ascension Declination Constellation Magnitude Angular Size
Spica (Alpha Virginis) 13h25m10s 11°09'S Virgo 1.1 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
16 Dec 1957 31 Jul 1968 Occultations of Spica (Alpha Virginis) 24 Sep 1968 15 Dec 1968
10 Jun 1968 25 Aug 1968 Occultations 31 Aug 1968 29 Sep 1968

The sky on 28 Jun 2024

The sky on 28 June 2024
Sunrise
05:20
Sunset
20:29
Twilight ends
22:37
Twilight begins
03:12


Waning Crescent

42%

22 days old

Planets
Rise Culm. Set
Mercury 06:30 14:03 21:35
Venus 05:50 13:23 20:56
Moon 00:24 06:28 12:44
Mars 02:13 09:11 16:09
Jupiter 03:25 10:47 18:08
Saturn 00:06 05:48 11:29
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.

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