Astroblog: Thursday September 17 to Thursday September 24

Tuesday, September 15, 2026

Thursday September 17 to Thursday September 24

The apogee First Quarter Moon is Saturday September 19. Saturn is rising at astronomical twilight. Mars forms a line with the bright stars Procyon and Pollux. Jupiter is low in the morning sky. In the evening, Venus is becoming brighter and is at maximum brilliance on the 19th. Mercury is low on the horizon. Earth is at Equinox on the 23rd when the day is more or less equal to night in length.

The First Quarter Moon is Saturday September 19. This is an apogee First Quarter Moon, when it is furthest from the earth. Earth is at Equinox on the 23rd when the day is more or less equal to night in length.

North-Eastern horizon on the morning of Saturday, September 19 as seen from Adelaide at 5:16 ACST (60 minutes before sunrise, click to embiggen).

Saturn is low above the north-western horizon. Mars forms a line with the bright stars Procyon and Pollux. Jupiter is low on the horizon.

Similar views will be seen from the rest of Australia at roughly the equivalent local time (60 minutes before sunrise).

Western sky on the evening of Saturday, September 19 as seen from Adelaide at 19:04 ACST (60 minutes after sunset, click to embiggen).

Venus is well above the horizon when the sky is fully dark. Venus is at maximum brilliance on the 19th.

The bright star Spica is below it and Mercury is low above the horizon.Mercury will rise higher in the twilight coming closer to Spica over the coming week.

Venus is a clear "Crescent Moon" shape and is increasing in size. The shape is readily visible in even small telescopes (although the brightness may make it hard to see).

Similar views will be seen from the rest of Australia at roughly the equivalent local time (90 minutes after sunset).

Eastern horizon on the evening of Saturday, September 19 as seen from Adelaide at 22:00 ACST (click to embiggen).

Saturn is the brightest object above the eastern horizon. Saturn is rising around 8:00 pm local time, but is still best for telescopic observation in the morning, and its rings are widening.

The inset shows the telescopic view of Saturn at this time.

Similar views will be seen from the rest of Australia at roughly the equivalent local time.

Whole sky on Saturday, September 19 as seen from Adelaide at 19:35 ACST, 90 minutes after sunset (click to embiggen).

Venus is prominent in the north-west. Saturn is visible low in the east

Scorpius, and the core of the Milky way are at the Zenith.

The Pointers are declining from their zenith in the Southern sky as the Southern Cross sinks to the south west. The Moon is waxing and the fainter clusters and nebula are becoming harder to see.

Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset).

Mercury returns to the evening twilight.

Venus leaves behind the bright star Spica and is becoming bigger and brighter. Venus is at maximum brilliance on the 19th.

Mars is low in the twilight. Mars forms a line with the bright stars Procyon and Pollux.

Jupiter climbs higher the morning twilight.

Saturn is in the northwest in the morning sky. It is now rising before astronomical twilight, but is best seen in the morning.

Printable PDF maps of the Eastern sky at 10 pm ACST, Western sky at 10 pm ACST. For further details and more information on what's up in the sky, see Southern Skywatch.

Star Map via Virtual sky. Use your mouse to scroll around and press 8 when your pointer is in the map to set to the current time.

Cloud cover predictions can be found at SkippySky.

Here is the near-real time satellite view of the clouds (day and night) http://satview.bom.gov.au/

Labels: weekly sky