Night Sky September 2020

2nd Moon will be at full phase. It will be opposite the Sun, being high above horizon most of the night. The fruit Moon (figure 1). Approximately 399000 kilometres from Earth. When reaching full phase, it will be in the constellation Aquarius (figure 2).

Figure 1: Fruit Moon.

Figure 2: Aquarius constellation.

9th (Epsilon) -Perseid meteor shower (figure 3 & 4). Active from 5 th to 21st ϵ . Maximum amount, of meteors on 9th . The radiant point will be above the horizon and therefore visible throughout the night. Best displays will be prior to dawn (06:00). It should be possible to view upto 4 meteors per hour at the peak of activity.

Figure 3: ϵ-Perseid meteor shower radiant point in constellation Perseus.

Figure 4: : ϵ-Perseid meteor shower.

22nd is the September (autumn) equinox (figure 5).

Figure 5: Autumn equinox.

The day of the equinox, everywhere on Earth has approximately 12 hours of day and night, as the Sun's annual journey through the constellations of the zodiac carries it across the celestial equator. The word equinox, derived from the Latin, aequus (equal) and nox (night). Wherever on Earth you are, on the day of the equinox the Sun will rise from the point on the horizon which lies due East, and sets beneath the point which lies due West. Equinoxes occur because the axis of the Earth's spin, its polar axis, is tilted at an angle of 23.5° to the plane of its orbit around the Sun (figure 5).

25th Close approach of Moon and Jupiter (figure 6). Visible in the evening sky, approximately 19:30 (BST) as dusk fades, 14° above Southern horizon. Reaching highest point at 20:15, 15° above Southern horizon. Continuing to be observable until approximately 22:50, when they disappear below 8° above South, Western horizon.

Figure 6: Close approach of Moon and Jupiter.

The Moon will be approximately 387000km from Earth, while Jupiter will be 715.5 million kilometres from Earth.  25th Close approach of Moon and Saturn (figure 7).

Figure 7: Close approach of Moon and Saturn. B

ecoming visible approximately 19:30 (BST) as dusk fades, 14° above Southern horizon. Reaching highest point at 20:45, 16° above Southern horizon. Observable until 23:35, when fading below 7° above South, Western horizon. Appearing in the constellation Sagittarius. The Moon will be approximately 387000km from Earth, while Saturn will be 1432.7 million kilometres from Earth. 27th Daytime Sextantid meteor shower (figure 8 & 9). Expected to reach peak activity approximately 07:00 (BST) on 27th . Radiant point rises above Eastern horizon. Source of the meteor shower is asteroid U2005UD.

Figure 8: Sextantid meteor shower.

Figure 9: Sextantid meteor shower.

WARNING: Never attempt to view through binoculars, telescope or any optical aid an object near to the Sun. Also, never attempt to view the Sun, aided or unaided, doing so may result in immediate and permanent blindness. Always use astronomical approved viewing equipment. The Stellarium software will assist greatly in locating objects in the sky.

Mark R Smith FRAS FRi


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