Dundee Astronomical Society
Sky Notes for August 2015
Now that the Venus Jupiter conjunction has passed it is time to look forward to the longer evenings
and hopefully clearer skies, it certainly has been a poor summer for viewing especially from my
location. Reports and images have been received from Ken Kennedy, Andy Heenan, Bill Samson and I
re the conjunction. Sky conditions have been variable with some individuals observing and others
not at all. Rather than put images here, Tony has put some on the website, so please have a look, for
those of us that observed, it was agreed that this was a magnificent sight. Of course we shouldn’t
forget New Horizons at Pluto and beyond on 14th July, more below.
Comet 141P/Machholz continues to move through Auriga at the start of the month, and by the end
of March moves into Gemini just west of Castor and Pollux. Tony Hayes has kindly offered to give a
large Kit Kat to the first person to send in a verified photo of the Comet.
Comet 67P/Churyumov – Gerasimenko will reach perihelion on 13th August when it will be closest to
the sun and is already beginning to become more active. There is a notion that the mission of
Rosetta may be extended after the primary mission objectives have been achieved, ESA are possibly
planning to soft land it on the comet very late 2016 as its fuel runs down. I think this would be fitting
end to a very daring mission.
Sky Map for 15th August 22:00
Illustration Courtesy of www.heavensabove.com
The Planets
Mercury
The planet isn’t well positioned this month in the evening sky at an altitude of 3 deg located in the
constellation of Leo, probably best viewed just after sunset at the start of August. On the 6th 7th
August Mercury and Jupiter will be located by less than 1 deg apart.
Venus
On the 15th August, Venus will be on the same side of the earth as the sun (inferior conjunction)
marking the planets transformation from an evening planet to a morning planet. Venus is quite low
in the sky now at around 6 deg and is located in Cancer. Best time to spot Venus in the morning
starts on the 24th August rising approximately 40 minutes before sunrise. Be careful if viewing
through a telescope or binoculars and take proper precautions.
Mars
Now gone from the evening sky and can be viewed at the start of August rising about 80 minutes
before the sun. Located in Cancer, Mars sits quite low in the morning sky at 12 deg.
Jupiter
Jupiter can still be viewed in the evening sky but is now very close to sun, so if want to view please
observe all the safety precautions require while viewing any object close to the sun. It is probably
not a great time for serious observing. Jupiter is located in Leo at an altitude of 3 deg.
Saturn
Located in Libra at an altitude of 16 deg, Saturn is probably past its best for observing. I managed to
get some images of Saturn on the evening of 20th June but was very hazy and the sky quite turbulent,
but maybe worth a try as the rings are quite open and a grand sight to behold.
Uranus
Is quite high in t he sky at 44 deg and reaches its highest point in the southern sky at the end of the
month. Located in Pisces with good weather and seeing you may be able to see it in a medium
telescope.
Neptune
With an 8” or larger scope you should be able to view Neptune, and possibly if you have a large
scope its moon Triton. 31st August at around midnight (UT) is probably best time to view, located in
Aquarius and at an altitude of 28 deg.
Pluto
Although not a planet by definition, Pluto is still worthy of a mention if only because of the New
Horizons encounter, so hopefully by the time this is published on the web, NASA will have released
more images of the dwarf planet and Charon.
The Moon
Third Quarter
August 7th
New Moon
Aug 14th
First Quarter
Aug 22nd
Full Moon
Aug 29th, Also known as a supermoon as the moon is opposite side of the
earth as the sun and will therefore be fully illuminated occurring at 18:35UT.
This is the first occurrence of 3 supermoons this year. The Native American
Indian’s named this as the full Sturgeon Moon because of the large number
of sturgeon fish in the great lakes that could be easily caught.
Meteor Showers
August 12th/13th brings forth the Perseids meteor shower and is probably one of the best meteor
showers to observe producing up to 60 meteors per hour at its peak (ZHR). The shower runs
annually from July 17th to August 24th with its peak this year on the 12th/13th and is famous for
producing a large number of bright meteors. Comet Swift Tuttle is the comet associated with this
shower, which was discovered in 1862 by Lewis A. Swift and Horace Parnell Tuttle. The radiant is
shown below, but of course the meteors can appear anywhere. With a new moon on the 14th, dark
skies are assured, but of course we need clear skies as well, let’s keep fingers and everything else
crossed.
NLC’s
Here we are coming into August, when NLC season should be reaching its peak, but again the
weather seems to be taking its toll at least in July with very little recorded activity. Only 1 report
from Ken Kennedy for the evening of 15th July “Broken cloud here but relatively faint NLC display
from about 2215 UT with type II and III forms, maximum elevation of 22 degrees and azimuth 355 –
045”. Andy Heenan has also confirmed Ken’s observation. Images are below. For the first time I have
actually seen NLC’s and captured an image, not a very good one so it won’t be included in this note
Jim’s Focus of the Month
Perseus
With the Perseids visible this month, I though a view of what’s around the constellation may add
some interest. Perseus is bounded by Andromeda to the east, Cassiopeia in the north along with
Cameloperdalis, Auriga in the west with Taurus and Aries to the south. Perseus, is named after the
Greek mythological hero Perseus.
Some interesting object to view in and around Perseus are the following:
NGC 884 and NGC 869 is a double cluster located in Perseus located near Eta Persei? This lovely pair
of clusters, which are among the youngest known in the galaxy, presents a rich array of scintillating
giant stars of contrasting colors.
NGC 1245 is a lovely open cluster and possibly a nice astrophotography opportunity.
NGC 1342 is a magnificent open cluster first observed by William Herschel in 1799. The cluster
consists of approximately 50 – 100 stars; the cluster itself is about 1170ly distant and estimated to
be 450 million years old.
NGC1499 also known as the California Nebula and is an emission Nebula, so called because its shape
resembles California on the west coast of the USA and lies at a distance of about 1,000ly from Earth,
the Nebula, not the west coast of America.
NGC 1528 is another open cluster lying at a distance of 1530 light-years away, William Herschel
described it in 1790 as “A beautiful cluster of large stars, very rich, and considerably compressed”.
Finally NGC 1545 is another open cluster and can be viewed in a small telescope.
Did You Know?
6th August 2012 Surveyor landed successfully on Mars using a Sky Crane to place the Lander on the
surface of Mars.
th
12 August 1977 saw the first test glide of Space Shuttle Enterprise
19th August 1646 John Flamstead the first English Astronomer Royal was born.
24th August 2006 Pluto was reclassified as a dwarf Plant by the IAU (shame on you).
25th August Sir William Frederick Herschel German born English astronomer who discovered Uranus
dies.
To add a bit of nostalgia, below is the first image taken of M31 In 1888.
Jim Barber
Director of Observations
Dundee Astronomical Society