(Please note all times are ST and are based on an observing location of Belfast and covers the month of September)
At the start of the month, the Sun rises at 06:30 and sets at 20:15. By month’s end, it rises at 07:25 and sets at 19:00.
Mercury is at greatest eastern elongation on the 14th, but is not visible this month.
Venus is visible very low in the evening sky, moving from Virgo to Libra during the month. At the start of the month, it sets at 21:05 and by month’s end, it sets at 19:55. It brightens from mag -3.9 to mag -4.1 during the month.
Mars is not visible this month.
Jupiter is visible in the evening sky in Capricornus during the month. During the month, it is visible as soon as darkness falls and by month’s end, it sets at 03:00. It fades from mag -2.7 to mag -2.6 during the month.
Saturn is visible in the evening sky in Capricornus during the month. During the month, it is visible as soon as darkness falls and by month’s end, it sets at 01:30. It fades from mag +0.3 to mag +0.5 during the month.
Uranus is visible in the evening sky in Aries during the month. At the start of the month, it rises at 21:55 and by month’s end, it rises at 20:00. It maintains its brightness at mag +5.7 during the month.
Neptune is at opposition on the 14th and is visible in the evening sky in Aquarius during the month. At the start of the month, it rises at 20:35 and by month’s end, it is visible as soon as darkness falls. It maintains its brightness at mag +7.8 during the month. It lies to the East of Phi (φ) Aquarii, mag +4.2.
The new moon is on the 7th (01:52) with the first quarter moon on the 13th (21:39). The full moon is on the 21st (00:55) with the last quarter moon on the 29th (02:57).
16th pm the 81% waxing gibbous lies SW of Saturn at 21:00.
17th pm the 89% waxing gibbous lies SE of Saturn and SW of Jupiter at 21:00.
18th pm the 95% waxing gibbous lies SE of Jupiter at 21:00.
20th pm the near full moon lies SE of Neptune at 21:00.
24th pm the 86% waning gibbous lies SE of Uranus at 22:00.
25th pm the 78% waning gibbous lies SW of M45 – The Pleiades at 22:00.
26th pm the 70% waning gibbous lies NE of Aldebaran (Alpha (α) Tauri, mag +0.9) at 23:00.
The best time to observe meteor showers is when the moon is below the horizon; otherwise its bright glare limits the number you will see especially the fainter ones.Below is a guide to this month’s showers.
There are no major meteor showers this month.
There may be additional minor showers this month, details of which can be found in the below Information Sources and Links Section. The ZHR or Zenithal Hourly Rate is the number of meteors an observer would see in one hour under a clear, dark sky with a limiting apparent magnitude of 6.5 and if the radiant of the shower were in the zenith. The rate that can effectively be seen is nearly always lower and decreases as the radiant is closer to the horizon. The Zenith is the overhead point in the sky.
Asteroid (2) Pallas is at opposition on the evening of the 11th at mag +8.5. It can be seen in Pisces and is visible as soon as darkness falls.
Finder charts and further information about other fainter asteroids can be found in the below Information Sources and Links Section.
There are no bright comets visible this month.
Finder charts and further information about the above and other fainter comets can be found in the below Information Sources and Links Section. Any of the above estimates are based on current information at the time of writing the guide and can be wrong – “Comets are like cats; they have tails, and they do precisely what they want”, David H Levy. “If you want to have a safe gamble, bet on a horse – not a comet”, Dr Fred Whipple.
On the deep sky front this month, galaxies M81 and M82 can be observed in Ursa Major. In Hercules, two globular clusters – M92 and the excellent M13 can be observed and in Lyra – M57 – The Ring Nebula can be observed. In Vulpecula – M27 – The Dumbbell Nebula can be found. In Andromeda, M31 – The Andromeda galaxy can be observed along with its satellite galaxies M32 and M110. In Perseus, there is the open cluster M34 and the excellent Double Cluster – NGC 869 and 884. In Triangulum, there is the galaxy M33. Finally Auriga is reappearing with its three open clusters M36, M37 and M38 as is Taurus with the excellent Pleiades – M45 and the Hyades.