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 04:50 and sets at 22:00. By the end of the month, it rises at 05:30 and sets at 21:30.
The Planets
Look out on the evening of the 1st after sunset and you will see
Saturn and
Venus lying less than 1 degree apart. It should be a spectacular sight.
Mercury was at Inferior Conjunction on the 28th of last month and becomes a morning object in July. It will be visible low in the East before sunrise from the middle of the month onwards. It is at Greatest Western Elongation on the 20th. By month’s end, it will rise at 04:00, one and half hours before sunrise and can be found in Gemini with a mag of -0.9.
Venus is now slipping into the evening twilight and will be at inferior conjunction next month. At the start of the month it sets at 23:55 and by month’s end it is barely staying ahead of the Sun, setting at 21:35. It dims during the month from mag -4.4 at the start to mag -4.3 by month’s end.
Mars is moving further away from the Sun and can be found low in the South East. At the start of the month, it rises at 01:50, and by month’s end, it rises at 00:30. It can be found in Aries during the month. It brightens from mag +0.7 at the start of the month to mag +0.5 by month’s end.
Ceres, the dwarf planet can be found this month to the South of Mars. It travels through the ‘head’ of Cetus during the month and is mag +9.
Jupiter is to be found low in the South East in Ophiuchus. At the start of the month, it sets at 03:20 and by month’s end, it sets at 01:15. It fades from mag -2.5 at the start of the month to mag -2.4 by month’s end.
Saturn is slipping into the evening twilight and will be at superior conjunction next month. It sets at 00:05 at the start of the month and by month’s end, it sets at 22:10. It maintains its brightness throughout the month at mag +0.6 and can be found in Leo.
Uranus can be found low in the South East in Aquarius. At the start of the month, it rises at 00:35 and by month’s end, it rises at 22:30. It maintains its brightness at mag +5.8 throughout the month.
Neptune can be found low in the South East in Capricornus. At the start of the month, it rises at 23:45 and by month’s end, it rises at 21:45. It maintains its brightness at mag +7.9 throughout the month.
The Moon
The last quarter moon is on the 7th, the new moon is on 14th with the first quarter moon on the 22nd. The full moon is on the 30th.
On the morning of the 4th, a waning gibbous moon lies close to
Neptune, to the East of the planet.
On the morning of the 6th, a 69 % illuminated waning gibbous moon lies less than 3 degrees to the East of
Uranus.
On the morning of the 11th, a 14% illuminated waning crescent moon lies less than 4 degrees to the East of the
Pleiades.
On the evening of the 16th, a waxing crescent moon lies less than 2 degrees to the West of
Saturn.
On the evening of the 17th, an 11% illuminated waxing crescent moon lies close to
Venus.
On the evening of the 25th, a 82% illuminated waxing gibbous moon lies 3 degrees to the South East of
Antares.
Jupiter, lying North of
Antares completes a stunning view.
On the evening of the 29th, moonrise occurs at 21:50 approximately. Watch out for the moon illusion effect.
On the evening of the 30th,
Neptune lies 3 degrees to the North of the just past full moon.
Meteors
This is a month of minor showers before the main event of the
Perseids next month.
We have the
Capricornids shower which has the potential for three peaks this month. The shower has a ZHR of 5 and the three peaks are predicted for the 8th, 15th and 26th. Lunar conditions for the first two are excellent with the last quarter moon on the 7th and the new moon on the 14th. Conditions for the third shower are not as good with a waxing gibbous moon approximately 82% illuminated setting at 01:40.
The
Alpha Cygnids peak on the 21st with a ZHR of 5. Lunar conditions are good with a 46% illuminated waxing crescent setting at 23:35.
The
Delta Aquarids have the first of two peaks. The second peak will be in August. For the first peak, the ZHR is 20, but unfortunately there will be major lunar interference as the moon will only be one day from full.
The
Pisces Austrinids peak on the 31st with a ZHR of 5. Unfortunately, as with the
Delta Aquarids, there will be major lunar interference as the moon this time will be one day after full.
Asteroids
Vesta can be found in Ophiuchus to the West of
Jupiter. It fades from mag +6.0 at the start of the month to mag +6.7 by month’s end.
Comets
Comet Linear C/2006 VZ13 is estimated to be mag +9 at the start of the month and will brighten slowly during the month and should be visible in binoculars. It is in Cepheus at the start of the month, moving through Draco and passing by Bootes and Coma Berencies before ending up in Virgo by month’s end.
Finder charts for locating the above and other
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 prominent. In Canes Venatici, there is M3 - a globular cluster and several galaxies including M51 - the Whirpool Galaxy and M63 - the Sunflower Galaxy. The globular clusters M13 and M92 can be found in Hercules. The galaxies M81, M82 and M101 can be found in Ursa Major. 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.
General Notes
The night sky does not get fully dark this month. Between May and the middle of August, Astronomical twilight is present at night. This is when the sun is between twelve and eighteen degrees below the horizon. 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 visible between the Northern latitudes of 50 to 65 degrees. 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
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
