SOUTHERN ASTRONOMER THE
MONTHLY MAGAZINE OF WORTHING ASTRONOMERS & WORTHING SKYWATCHERS
The Southern Astronomer No.94 – July 2016
WORTHING ASTRONOMERS No fees, no Committee; just enjoying the night sky together.
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ormed in 2008 by a group of regular and practical observers, Worthing Astronomers is a free to join society now with a membership of over 450 persons, who have a common interest in Astronomy and its associated subjects – no internal politics, no fees, no committees, just astronomy!
The Southern Astronomer This Issue
Our aim is simple – to bring astronomy to the public in general and to help and assist our membership in observing the night sky. With the aid of this newsletter, website, social media, regular star parties, workshops and public observing events we hope to encourage and share our interests in observing the sky with the public, our colleagues in our own group and with those of neighbouring astronomical societies. We try and meet at least once a month (when sky conditions allow) to do some observing but we do hold every two months a Workshop evening when we get a chance to meet up, exchange ideas and tips and help each other to make the most of observing the sky above us. Occasionally a guest speaker will talk about an aspect of practical, hands on astronomical observing or photography.
Astronomy This Month
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Observing Planets
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Meteors; The Sun;
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June Workshop Report
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Monthly Sky Map
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Cover Picture: Andy Li caught the star clouds of the Milky Way as they appeared from Ferring to the west of Worthing. They are a stunning sight and as I mention on page 6 I place observing these clouds along with solar eclipses and aurora as must see things in astronomy.
These Workshop evenings are held on the first Friday of every other month (February, April, June, August, October and, December) at Goring Methodist Church Hall, Bury Drive (off of Aldsworth Avenue), Worthing, BN12 4XB. The admission charge of £3 helps pay for the room and free refreshments and goes towards supporting our membership. Doors open at 7.00 pm with the meeting starting at 7.30.
If we do get to see some clear skies (as I write, rain is falling from grey leaden skies – flaming June indeed!) over the summer period try and get to a dark sky site with a good southern horizon and get a glimpse of them.
We can be found at: worthingastronomers.org.uk
Contact addresses: info@worthingastronomers.org.uk – general society details Brian Halls
There are several astronomical groups in the coastal area of Sussex - several WA members are also members of the Adur Astronomical Society, who meet every first Monday of the month for a lecture regarding an astronomical subject. Details for AAS can be found at Adur Astronomical Society
treasurer@worthingastronomers.org.uk – donations contact Janet Halls outreach@worthingastronomers.org.uk – events contact Steve Bassett, Mike Williams
CONTRIBUTIONS AND UNSUBSCRIBING
website@worthingastronomers.org.uk – contact for website Perry Wilkins
Contributions – written articles (preferably word processed in .txt, .doc or .odt format), photographs or letters to the editor for the August issue should be in by July 15 and sent to the editor at the contact address: editor@worthingastronomers.org.uk
editor@worthingastronomers.org.uk – content detail Brian Halls
If you no longer wish to subscribe to the group and cancel newsletters and other information, please send an email to: info@worthingastronomers.org.uk with 'Unsubscribe' in the subject line; we do not want our stuff to end up like spam littering your inbox. Volunteers are always welcome: if you want to find out more, call 01903 521205 or drop us a line at the e-mail address above. If you like the newsletter or its content please feel free to distribute it to anyone you know who might be interested. Content is subject to copyright to the group and/or the individuals whose images or articles are used.
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The Southern Astronomer No.94 – July 2016 DEEP SKY OBJECTS
ASTRONOMY
THIS MONTH
July 2016
All times are expressed as Universal Time (UTC – Co-ordinated Universal Time) and can be considered the same as GMT (i.e. BST minus one hour.) Planets information, and all sky-map on page 6 is for the 15th of the month at 21.30UT unless otherwise stated. The Summer Solstice passed a couple of weeks ago so the evening skies remain bright – sunset remains the same time a few days after the Solstice. The darkness of late evening is worth waiting for as the Milky Way rises in the east and passes overhead as the night progresses. QUICK VIEW DIARY 1 4 5 7 12 13 16 19 26 27 31
Sunrise 0353h : Sunset 2022h Moon at perigee (06h) New Moon (11h) Earth at aphelion – furthest from Sun in its orbit (15h) Juno Probe rendezvous with Jupiter (03h) Mercury at superior conjunction (03h) Moon: First Quarter (01h) Moon at apogee (05h) Close conjunction of Mercury and Venus Full Moon:Trad. English, Hay Moon (23h) Moon: Last Quarter (23h) Moon at perigee (12h) Sunrise 0427h : Sunset 1952h MOON PHASES IN JULY
SUBJECT TYPE
Constellation
MAG
RA (h m)
DEC (° ' )
NGC6140
Galaxy
Draco
11.3
16 21.0
+65 23
NGC6236
Galaxy
Draco
11.9
16 44.6
+70 47
NGC6340
Galaxy
Draco
11
17 10.4
+72 18
NGC6412
Galaxy
Draco
11.8
17 29.6
+75 42
NGC6503
Galaxy
Draco
10.2
17 49.5
+70 09
NGC6543
Planetary Neb
Draco
8.3
17 58.6
+66 38
IC4593
Planetary Neb
Hercules
11
16 11.7
+12 04
NGC6205
Glob Cluster
Hercules
5.9
16 41.7
+36 28
NGC6341
Glob Cluster
Hercules
6.5
17 17.1
+43 08
NGC6166
Galaxy
Hercules
11.8
16 28.6
+39 33
NGC6181
Galaxy
Hercules
11.9
16 32.3
+19 50
NGC6207
Galaxy
Hercules
11.6
16 43.1
+36 50
NGC6210
Planetary Neb
Hercules
9.7
16 44.5
+23 48
NGC6229
Glob Cluster
Hercules
9.4
16 47.0
+47 32
NGC6482
Galaxy
Hercules
11.4
17 51.8
+23 04
IC4665
Open Cluster
Ophiuchus
4.2
17 46.3
+05 43
NGC6254
Glob Cluster
Ophiuchus
6.6
16 57.1
-04 06
NGC6218
Glob Cluster
Ophiuchus
6.6
16 47.2
-01 57
NGC6402
Glob Cluster
Ophiuchus
7.6
17 37.6
-03 15
NGC6171
Glob Cluster
Ophiuchus
8.1
16 32.5
-13 03
NGC6309
Planetary Neb
Ophiuchus
11.6
17 14.1
-12 55
NGC6356
Glob Cluster
Ophiuchus
8.4
17 23.6
-17 49
NGC6366
Glob Cluster
Ophiuchus
10
17 27.7
-05 05
NGC6384
Galaxy
Ophiuchus
10.4
17 32.4
+07 04
NGC6440
Glob Cluster
Sagittarius
9.7
17 48.9
-20 22
NGC6217
Galaxy
Ursa Minor
11.2
16 32.6
+78 12
NGC6324
Galaxy
Ursa Minor
12.8
17 05.4
+75 24
© Joshborup
NGC 6205 or as it is better known M13, is a relatively bright star cluster in Hercules comprising something like 300 000 stars and is about 25 000 light years away (see above list for details). The above image is a detail from an original image obtained with an 80mm refractor.
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The Southern Astronomer No.94 – July 2016
The planets mid-month (comparative angular diameters) – timed at 21.30UT
OBSERVING THIS MONTH:
PLANETS B
oth Mercury and Venus lay close to the Sun in the evening sky mid-month. The rapidly moving Mercury starts the month as a morning star – again, close to the Sun; by the time the end of the month comes it will be setting just after the Sun in the evening. Venus is slowly making its way into the evening sky as mentioned above, it lays close to the Sun. On the evening of July 16 the two planets are in conjunction with each other but, laying only 11° from the bright Sun - a good (near cloudless and hazeless) western horizon may be needed to see them just after sunset about 20hUT onwards for a brief 40 minutes or so, window of opportunity. The Sun sets at 20.12UT; Venus sets at 20.50UT while Mercury sets at 20.52UT. Mars, Jupiter and Saturn are already well up in the sky as darkness falls. From the Coellix Lite planetary diagram at the top of the page, it can be seen that over the space of the month, Mars shrinks in size – from 16.3” to 13.1” (arcseconds) as the Earth and Mars now distance themselves due to their orbits (Earth moving faster than Mars.)
Visibility of the planets and Moon, mid-month
The smaller gas giants, Uranus and Neptune begin to make an appearance in the night time sky. For most of us, these objects are nothing more than tiny coloured disks in a moderate telescope however those with larger instruments have observed white ‘spots’ on Neptune. A BAA email circular reports: On 11 June at 12:51UT, Australian amateurs Darryl Milika and Pat Nicholas imaged two bright spots on Neptune using a C14 and IR 610nm filter. These spots have been confirmed by Ricardo Hueso in professional observations made by the team at the Calar Alto observatory in Spain using a 2.2m telescope...on 17 May. One has also been
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imaged by the Hubble Space Telescope. Naturally, a large instrument is best for this kind of observation but, it is possible for amateurs to make the observations of planets and pass on any interesting observations which the professional astronomer and their telescopes (usually assigned to more specific observational work) can then be used. On the early morning of July 5, the NASA probe which hopes to understand the origin and evolution of Jupiter, look for a solid planetary core, map its magnetic field, measure water and ammonia in the deep atmosphere and, observe aurorae.
The Southern Astronomer No.94 – July 2016
METEORS & SUN COMETS WATCHING S T
actual smoothed average based on observational data.
As this newsletter was being put together, the Sun once more produced a blank disk over several days thus bracketing June as a low sunspot month.
unspot activity switched off temporarily in early June (June 3 to 7) when, for the first time since We had seen a decrease in sunspots during May but Brian States observed the Sun on 29 days 2014 there were four spotless days. Indeed, that during the month producing an average daily makes a total of five spotless days since 2012. sunspot number of 40.1 (BAA = 39.8; AAVSO= The most famous of the summer meteor showers is the Perseids which start about July 17 and comes Sunspot activity is now in the declining phase of the 43.1) – there were no spotless days! to its climax during August 12. present sunspot cycle. As can be seen from the How will the future pan out? There is no doubt that Space Weather Center chart below, the present cycle is producing on average far lower numbers of this solar cycle is a low one where the number of sunspots are concerned. This appears to uphold a sunspots and groups when compared with the previous ‘quiet’ cycle that was with us at the turn of suspect period where sunspot numbers decrease every hundred years or so. the century. here are several meteor showers forecast for the month.
This present cycle is also confounding the experts as A low period in the early nineteenth century was the red predicted average (or ‘smooth’) value (red, named the Dalton Minimum which appeared to coincide with some extremely cold winters. lower right on chart) is actually higher than the
At the start of the shower epoch, the Perseid radiant is in the Milky Way close to Cassiopeia (above) and will make its way, night by night towards the Perseus constellation. While the Perseids are towards the north-east portion of the sky, to the south is the constellation of Aquarius and the Delta Aquariids shower which peaks July 28 (lower right.) The Moon is bright in the sky from mid-month for about ten days and may cause problems with observing some fainter meteors. OBSERVING As with many meteor showers the visible rate is greatest in the pre-dawn hours, since more meteoroids are scooped up by the side of the Earth moving forward into the stream, corresponding to local times between midnight and noon - while many meteors arrive between dawn and noon, they are usually not visible due to daylight. Some can also be seen before midnight, often grazing the Earth’s atmosphere to produce long bright trails and sometimes fireballs. Most meteors burn up in the atmosphere while at heights above 80 kilometres (50 miles). Naked eye observation of meteors is one of the easiest and most pleasant form of work open to the amateur astronomer. Even a beginner can make useful observations, and it is a good way to learn the constellations. Meteor work is excellent for clubs and societies with little or no equipment; essentially only the human eye is needed. A sun lounger is useful so the observer can lay in a comfortable position and look up at the sky watching for meteors. A star map, accurate time piece and a note pad to record the observations are also very handy to have. The wide use of digital cameras to capture meteors is useful.
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The Southern Astronomer No.94 – July 2016
JUNE WORKSHOP June 3
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well attended meeting welcomed our guest speaker, Dan Oakley of the South Downs National Park (SDNP) which has now added to its title since he last spoke to us, International Dark Sky Reserve or as Dan calls it, Moore’s Reserve in honour of the late Sir Patrick Moore. A Dark Sky Reserve is defined as ‘...a public or private land possessing an exceptional or distinguished quality of starry nights and nocturnal environment that is specifically protected for its scientific, natural, educational, cultural, heritage and/or public enjoyment mission of a large peripheral area.’ Dan described in his own unique style how the SDNP had gone about getting Dark Sky Reserve status and the various hoops that needed to be jumped through along with numerous crossing of ‘t’s and dotting of ‘i’s.
It meant traveling around towns, villages and countryside of the SDNP at night taking measurements of the how dark the sky was from various locations as well as noting the types or lighting that was used in various places. He had given them names – for example, Domesticus Luminarous or the common house lamps, ranging from ssp. Muchos Blindyeye (floodlamp), Heritago Allovertheplacus (ornamental coach lamp) and the Ugly Bugly (bulkheads.) It was just not the home lights but street lights that were surveyed – Darkus Superior (street lights using LED’s that cast their light downwards) for example and poor lighting such as the Frickin Illuminati (football pitch lights) and the Maximus Pollutus Crapus (ornamental lamps that throw their light up into the sky.) The former is being tamed by lighting authorities while the latter is heading for total extinction.
Dan richly illustrated his presentation with informative graphs and charts which showed the percentage of the differing kinds of domestic lighting – floodlamps for example make up just over 20% of light pollution and how lighting levels can change through the evening and into the night with late hours of the night (or early wee hours post midnight) being the best for dark skies. Dan showed the panoramic image (lower left) which he had made from where he lived in the SDNP. The south-east to south-west skies are polluted at the horizon by human coastal occupation with the northern skies being much better. Of course it is just not the astronomer who seeks or needs the dark skies. Dan listed the wildlife affected by light pollution and not always directly - for example moths are affected by adversely by light pollution and this will have a knock on affect on the wildlife that feeds on them. On a light conclusion, part of Dan’s remit is to promote both the SDNP and the Dark Sky Reserve angle. Many younger people seem to be left in the cold by the Greek mythological figures that inhabit our western star-lore so he has bought up to date for the 21st-century with a more modern set of heroes (and villains.)
What youngster has not heard of Harry Potter? There is an H in the sky in the form of the constellation we know as Orion. A small stretch of the imagination and we can see Harry there, wand in right hand pulled back and ready to strike while in his left he holds the cloak of invisibility. Who is he striking against but the V of Voldermort (our Taurus) even the star Aldebaran as the glinting red-eye of the evil one might excite a youngster. The Weasley Twins are of course Gemini and the Image: Dan Oakley Pleiades are the Seven Horcrux and so on. After the presentation Dan fielded some questions from the floor and an appreciative audience showed their thanks in the usual way. IOS ASTRONOMY APPS The next speaker was Andy Li who had responded to a request from a member regarding an introduction to astronomical apps for mobile devices.
When purchasing it is important to look for an app that gives you what you might need – such as, a good listing of deep sky objects in the form of Messier or NGC listings as well as a list of what is visible in the form of ‘Tonights Best’, deep sky object images, planetary and lunar features list, virtual reality or GPS functions, field of view calculators.
Andy then went on to show screen shots from Andy uses an iPhone and so this was very much some of these various apps, how they compared orientated around the apps available for download in with each other, what they gave (or didn’t give). the Apple Store, however many of these apps were also available for Android and Windows tablets and Some better known names also produce apps. phones. Sky & Telescope produce astro-apps that are portable versions of some of their utilities that Many of the apps available can be described as appear on their website. planetaria – sky maps showing the constellations and objects within them at any time. The usual Of course it is not just looking through the process is to open the app and and hold it up to the telescope apps that astronomers can find useful. sky and one can see what constellations, planets deep sky objects etc are visible if the Sun and/or Andy covered these – such as weather apps (very cloud (!) were not obstructing our view. useful when planning an observing session) and a telescope alignment app that helps someone Andy listed several – Sky Safari, Luminos, setting up an equatorial telescope the accurate Goskywatch, Night Sky Pro, Sky Guide, Sky Walk location of the north star Polaris, which is very and Stellarium. Most of these are available for useful when planning to take images of faint purchase at a few pounds. The oddity is Stellarium objects that require accurate tracking. which is free as a computer app. Available also are apps from NASA and other
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sources which give information as to the visibility of the International Space Station and other artificial satellites orbiting the Earth. Due to lack of time, the presentation, ‘How to Make 50 Shades of Grey More Colourful’ will be held over to another workshop. Many thanks to Dan and Andy who spoke and the informative and fascinating presentations they put together. Thank you also goes to those who helped with the refreshments and Jan Halls who sat at the door welcoming those who came in. Steve Bassett, in response to a suggestion from members trialled streaming some of the meeting onto the internet via the Worthing Skywatchers Facebook page. The experiment went fairly well – we shall be looking into the technicalities of trying to get this to be a regular feature so members who are unable to attend can still share in with what is going on. Our next Workshop is on August 5 – have you an idea as to what might be suitable subjects for discussion or would like to learn some more about? If so, drop us a line at: info@worthingastronomers.org.uk
The Southern Astronomer No.94 – July 2016
Graphic: Stellarium
An all sky view in mid July at about 21.30 UT
As we can see, the thickness of the Milky Way is in the southern sky during the middle part of the evening. The centre of the galaxy is positioned within Sagittarius though for us northern hemisphere observers we can never get to see the dark clouds of gas and dust that obscure the core of galaxy from view. From a dark sky site, the clouds of stars we see can be quite stunning. I have been lucky to see solar eclipses and bright aurora during the many years I have been interested in astronomy. If ever you get a chance to see one of those do so, now is the time to see one of the other most awe inspiring sights one can see in my opinion – the star clouds of Sagittarius hanging over a sea horizon. We are starting to lose Jupiter to the south west but both Mars and Saturn are still in good positions to observe. Almost overhead are the constellations of Hercules, Corona Borealis, the kite shaped Bootes while to the east are the three bright stars Vega in Lyra, Deneb in Cygnus and Altair in Aquila that form the asterism (an unofficial star name) of the Summer Triangle. To the south region of the sky is the red planet Mars, while a bright red star further to the east is Antares. The planets are named after the Roman gods which they basically nicked from the Greeks. In Greek, Mars is Ares and Antares can be translated as Rival to Ares so the positioning of the two bright red objects at the moment is appropriate.
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