Hi all,
Enjoy the below observing guide for September.
OBSERVING GUIDE
(Please note all times are BST and are based on an observing location of Belfast)
The Sun
At the start of the month the Sun rises at 06:30 and sets at 20:15. By the end of the month, it rises at 07:25 and sets at 19:05.
The Planets
In the early hours of the 17th,
Mars passes less than a degree to the West of
M1 - The Crab Nebula.
Asteroid (194) Prokne (mag +9.7) passes less than a degree to the West of
Neptune at the end of the month. Check out
www.calsky.com
for exact coordinates.
Mercury is at Greatest Eastern Elongation on the 29th, but the shallow angle that the plane of the Solar system makes with the Western horizon at sunset means the innermost planet is very badly placed for observation this month. At the start of the month, it sets half an hour after the Sun at 20:45 and by month’s end is setting only fifteen minutes after the Sun at 19:20.
Venus is a prominent morning object this month, rising an hour and half before the Sun at the start of the month at 05:05 and by month’s end it rises at 03:30. It brightens from mag -4.3 at the start of the month to mag -4.5 by month’s end.
Mars rises at 23:20 at the start of month and by 22:15 by month’s end. It moves into Gemini by month’s end from Taurus and brightens from mag +0.3 at the start of the month to mag -0.1 by month’s end.
Jupiter is to be found low in the South East in Scorpius. At the start of the month, it sets at 23:10 and by month’s end, it sets at 21:25. It fades from mag -2.2 at the start of the month to mag -2.0 by month’s end.
Saturn has become a morning object. It rises one hour before the Sun at the start of the month at 05:35 and by month’s end, it rises at 04:05. It can be found in Leo and fades from mag +0.6 at the start of the month to mag +0.7 by month’s end.
Uranus can be found low in the South East in Aquarius. It is at opposition on the 9th. It rises at 20:25 at the start of the month and by month’s end, it rises in daylight and sets at 05:30. It maintains its brightness at mag +5.7 throughout the month. On the 1st, it is placed less than a degree to the North-West of Phi Aquarii, a mag +4.2 star. It moves away from Phi Aquarii throughout the month towards Lambda Aquarii, a mag +3.7 star.
Neptune is still well placed for observation having been at opposition last month. It can found low in the South East in Capricornus, within several degrees to the North West of Gamma Capricorni, a mag +3.7 star. At the start of the month, it rises during daylight hours and sets at 04:50 and by month’s end, it sets at 02:55. It fades from mag +7.8 at the start of the month to mag +7.9 by month’s end.
The Moon
The last quarter moon is on the 4th, the new moon is on 11th with the first quarter moon on the 19th. The full moon this month is on the 26th and is known as the Harvest Moon as it is the closest full moon to the autumn equinox.
On the morning of the 3rd, a 61 % illuminated waning gibbous moon lies 2 degrees to the West of
M45 - The Pleiades just before sunrise.
On the morning of the 8th, a 11% illuminated waning crescent lies less than 2 degrees to the North-West of
M44 – The Beehive Cluster just before dawn.
On the morning of the 10th, a 1% illuminated waning crescent may be observed just before dawn in the East. Moonrise will be at 05:20.
Saturn will lie in close proximity to the North.
On the evening of the 23rd, a waxing gibbous moon lies close to
Neptune, to the South of the planet.
On the evening of the 25th, a 98% illuminated waxing gibbous moon lies 3 degrees to the North-East of
Uranus.
Meteors
This is a month of minor showers. First up is the
Alpha Aurigds which peak on the 1st/2nd with a ZHR of 9. A 73% illuminated waning gibbous moon may interfere with the shower.
The
Gamma Aquarids peak on the 7th/8th with a ZHR of 4. There will be little or no lunar interference for this shower as the waning crescent moon only rises at 02:35 on the morning of the 8th and at 04:00 on the morning of the 9th.
The
September Perseids peak on the 9th with a ZHR of 5. There will be little or no lunar interference for this shower as the waning crescent moon only rises at 05:20 on the morning of the 10th.
The
Piscids peak on firstly the 8th with a ZHR of 10 and then on the 21st with a ZHR of 5. There will be little or no lunar interference for the first peak as the waning crescent moon only rises at 04:00 on the morning of the 9th. The second peak may have some lunar interference for a while, as the 71% illuminated waxing gibbous moon sets at 00:30.
Comets
There are currently no bright comets visible. However weekly updates on comets can be found at
www.aerith.net
and finder charts for locating comets can be found at;
www.skyhound.com/sh/comets.html
Deep Sky
On the deep sky front this month, the summer triangle of Deneb in Cygnus, Vega in Lyra and Altair in Aquila is still prominent. Check out NGC 7000 – the North America Nebula in Cygnus. It lies 3 degrees to the East of Deneb. The globular clusters M13 and M92 can be found in Hercules. M31 – the Great Andromeda Galaxy can be found in Andromeda, along with its two satellite galaxies – M32 and M110. M33 – a good spiral galaxy can be found in Triangulum. The Double Cluster – NGC 869 and NGC 884 makes for a great sight in Cassiopeia. M57 – The Ring Nebula lies to the South of Vega, roughly a quarter of the way between Vega and Altair and in Vulpecula, M27 – the Dumbbell Nebula can be located.
For further observing information, check out
www.eaas.co.uk/stargazers.html
.
General Notes
The autumn equinox is on the 23rd which sees the end of summer and the beginning of autumn. Always keep an eye out for Aurorae. Check out
www.stronge.org.uk/spaceweather.html
for the most up-to-date information on the aurorae.
Watch out for
NLCs - Noctilucent Clouds this month. They are also known as Polar Mesospheric Clouds as they are thought to be due to water ice particles up in the mesosphere. They are most commonly visible between the latitudes of 50 to 70 degrees both North and South of the Equator. Look to the North for a white/silvery glow. They can sometimes be faint, sometimes bright.
Other interesting naked eye phenomena to look out for include the
Zodiacal Light and the
Gegenschein. Both are caused by sunlight reflecting off dust particles which are present in the solar system. The
Zodiacal Light can be seen in the West after evening twilight has disappeared or in the East before the morning twilight. The best time of year to see the phenomenon is late-Feb to early-April in the evening sky and September/October in the morning sky -- it's then that the ecliptic, along which the cone of the zodiacal light lies, is steepest in our skies. The
Gegenschein can be seen in the area of the sky opposite the sun. To view either, you must get yourself to a very dark site to cut out the light pollution. Moonlight also hampers the view.
Finally check out
www.heavens-above.com
for the latest passes of the ISS and for details of Iridium Flare activity.
Clear Skies
Neill McKeown
