WADHURST ASTRONOMICAL SOCIETY

JULY NEWSLETTER 2007

INDEX: MEETINGS, OTHER NEWS, CONTACTS

MEETINGS

COMMITTEE MEETING

Members of the Society's Committee are respectfully reminded that the next Committee Meeting is to be held at the Abergaveny Arms in Frant on Monday the 9th of July beginning at 1930.

As always, any member of the Society is very welcome to join us.  The meeting usually lasts an hour and is always held in a relaxed and pleasant atmosphere.

JUNE MEETING

As the June meeting was held on the shortest night of the year the Society held an open evening when members were invited to bring telescopes, photographs, books and other aids to astronomy, giving members the chance to talk about their experiences and projects in an informal way.  It turned out to be a very full and varied evening.

There were six telescopes altogether including:

The Ian Reeves Konus 120 mm refracting telescope

A 5-inch Schmidt reflecting computer controlled telescope

A 66 mm and an 80 mm refracting telescope both with Williams Optics

An 11-inch Celestron Schmidt-Cassegrain Catadoioptric telescope with German Equatorial driven mount

A 40 mm hydrogen-alpha Coronado PST (Personal Solar Telescope).

It may be worth mentioning at this point that the Ian Reeves telescope belongs to the Society and is available for any member to borrow.

A visitor to the meeting said that he was visiting the town and had seen our meeting announced on the Wadhurst Town notice board.  He was from Hertfordshire but had with him a series of photographs showing how he had constructed an 18-inch reflecting telescope on a specially made fork mount.  It had taken him a total of fourteen years to complete but was a very impressive instrument mounted in a specially constructed observatory.

Astrophotography 

The highlight of the evening was Phil Berry's illustrated talk about astrophotography.  He began by saying that after some of our recent excellent talks, some members felt that they needed a Faulkes telescope to enter the field of astrophotography but Phil explained that this was quite wrong and anyone with little equipment could produce very satisfying results.

An interesting observation is that atmospheric turbulence can be more degrading on telescopes greater than 8-inches!

One of the biggest advantages amateurs have is time. They can afford to take many short exposures and with available computer software, - often free, can reassemble many faint images in quite remarkable detail, even though very small CCD cameras are used.

For Phil's presentation he said he had borrowed some images from Ian King, another of our members, and began by showing us NGC 4631, an edge-on spiral galaxy taken with an 8-inch reflector.  The galaxy is in the constellation of Canes Venatici and has an apparent magnitude of +9.3.  The image also revealed a gaseous cloud, which had a temperature of well over a million degrees Celsius.

NGC 6888 is a Super Nova remnant, 20 minutes across.  The shape clearly showed the advance of the material thrown off during a gigantic explosion that took place about 400,000 years ago.

Phil had with him his Coronado 40 mm Personal Solar Telescope (PST) and explained that he had been able to make some remarkable observations of the Sun in hydrogen alpha light.  He used an image that Mathias Bopp in Germany had achieved using a web cam on an identical telescope to illustrate what could be achieved with affordable equipment.

Images of more familiar sights were illustrated by an image Phil had obtained with his 80 mm reflector of the Pleiades, M45. The cluster is 110 minutes wide with a magnitude of +1.2.  Seen with the naked eye, usually only the "Seven Sisters" can be seen but there are many hundreds of stars within the cluster.  In Phil's image the dust and gas around the cluster showed up clearly as a sweeping blur of the brighter stars.

Phil talked of one effect he had discovered when using his 5-inch Schmidt telescope, which had exhibited itself as very small corrections both in the RA direction and the Dec direction causing the corrections during a timed exposure to zig-zag.  He cured this effect by setting the telescope's wedge to the latitude of the telescope so that only tracking in one direction was achieved.

We were shown an incredible image of M31, the Andromeda Galaxy, taken by Ian King for which he had been awarded the Astronomy Now magazine award of the year a few years ago (massive 25!)

To show what was possible we were able to compare an image of M51, a spiral galaxy close to Alkaid, the last bright star in the handle of the Plough taken by the Hubble Space Telescope, and then we were shown the same galaxy taken using an 8-inch reflector.  With use of computer software to reduce the contrast, the image taken with the 8-inch appeared clearest which showed what the amateur with very modest equipment could achieve.

Finally, Phil showed a picture of himself next to the Hubble Space Telescope!  Then he explained that two Hubbles had been built in case one failed and now the second one is exhibited at the Smithsonian Space Museum in Washington.  Phil was absolutely dwarfed by the 13.2 metre high space satellite!

In conclusion, Phil said we have the time to produce great images even with small resources.

Digital SLR Cameras and Astronomy 

At the meeting Bob Seaney asked if any one had had any results using digital SLR cameras on the night sky.  He has a camera with a 6 x zoom and was interested in hearing other people's experiences.

Bob also showed a number of planetary photos he had made using the Meade Lunar Planetary Imager (LPI).  The images were very good for an imager that fits any telescope and downloads straight to a computer.  Once again proving Phil right about using affordable equipment.

JULY MEETING

Wednesday 18th July 2007   George Satterthwaite will be giving a talk about "George Airy and His Contribution to Positional Astronomy".

As usual, the meeting will be held in the Upper Room of the Methodist Church which is at the southeast end of Wadhurst High Street, opposite Uplands College.  The meeting is due to start at 1930.

FUTURE MEETINGS & EVENTS

Monday 9th July 2007  Meeting of the Committee 1930 at the Abergaveny Arms, Frant

August  There is no meeting of the Society in August, but once again, we have been kindly invited to an Astro Barbecue hosted by Michael Harte and his wife at Greenman Farm on Saturday 25th August 2007.

Greenman Farm, Wadhurst, is on the south side of the B2099 immediately to the west of the railway over-bridge.  All Society members are invited and Michael suggests that members aim to arrive at about 7.00 pm.

You will only need to bring your own food and drink, as everything else will be provided.

In previous years this has been a very enjoyable event and gives members a chance to meet others in a relaxed and enjoyable atmosphere.

Members are invited to bring telescopes, binoculars and anything else of interest, but mainly themselves.

Adding a note of caution.  It is late August and can be a bit cold as the evening progresses, so it might be worth bringing some warm clothing.

  Wednesday 19th September 2007   George Sallitt will be giving a talk about "Web cams", a subject that will interest many members keen to get involved with this cheaper but surprisingly satisfying method of imaging.

Saturday 22nd September 2007  A visit to see the largest private collection of clocks in the UK at Belmont House near Faversham in Kent.  Details later in the Newsletter.

Wednesday 17th October 2007  Keith Brackenborough will be giving a talk with the intriguing title "The Calendar - A 5,000 year struggle  to Align the Clock to the Heavens".

Wednesday 21st November 2007  John Vale-Taylor is presenting "The Tim Bance Interview".  Tim is a long-standing member of the Society and has a wealth of practical experience in the field of amateur astronomy.

Wednesday 12th December 2007  NOTE: THIS IS THE SECOND WEDNESDAY OF DECEMBER   Society Member, Paul Treadaway is giving a talk he calls "Why are we Still Here?" - Food for thought...

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OTHER NEWS

VISIT TO BELMONT HOUSE

On Saturday the 22nd of September, The Society is visiting one of the finest collections of clocks in Britain.  Members going have already given their names to Phil Berry but anyone else wishing to go should contact Phil by the July meeting so that he has the number of members going.  His telephone number is in the Contacts list at the end of the Newsletter.

We will need to find our own way there in our own transport.  The house is in its own grounds and directions to get there are as follows:

From Ashford / M20, exit junction 9

Take A251, heading North in the direction of Faversham.  Pass through the village of Boughton Aluph (2 miles), straight across the Challock roundabout (4 miles) and continue North until Badlesmere. Turn left and follow the brown Tourist signs for Belmont; a further 1.5 miles.

From Faversham / M2 exit junction 6

Turn onto A251 heading South in the direction of Ashford.  Pass successively through the villages of Norton (2 miles) and Sheldwich (3 miles), before reaching Badlesmere (4 miles), turn right and follow brown tourist signs for Belmont; a further 1.5 miles.

TELESCOPE FOR SALE

Bob Seaney is selling an eight-inch LX 10 reflecting telescope.  This is an ideal telescope for the more serious amateur and would provide the opportunity to get involved in more fundamental observing.

The telescope, which is in excellent condition, has its own travelling box.  It has an equatorial battery driven mount with hand controls.  The instrument takes standard one-and-a-quarter-inch eyepieces and comes with a 40 mm eyepiece.

The telescope has a heavy metal tripod for good stability.

Bob is asking 450, which is very reasonable and he can be contacted on telephone number 01580 752350.

REQUEST FOR A SPEAKER FROM THE NATIONAL TRUST

Our Chairman has received a request from the National Trust at Bateman's asking for someone to give them a talk about astronomy.  The talk would need to be about 60 to 90 minutes and would be scheduled for sometime next year.

The idea came from one of the gardeners whilst gazing up at their unpolluted night sky.

Further information may be obtained from John Vale-Taylor.

SAGAS

SAGAS, the Southern Area Group of Astronomical Societies, is holding their Summer Event on Saturday the 14th of July and members of our Society are invited to attend.  The meeting is being hosted by the Vectis Astronomical Society on the Isle of Wight.

The event will take place at the Isle of Wight Observatory, Watery Lane, Newchurch Near Sandown, I.O.W. Grid ref:  SZ554843.  The cost is 5, which covers all costs, refreshments and a light lunch.

The provisional timetable is:

1100 Delegates arrive at observatory

1300 Lunch

1430 Meeting

1730 approximately, - end

Speakers will be:

John Mason (Chichester Planetarium) "Mars Exploration Update"

Ninian Boyle  (Venturescope) - "Solarscopes"

Peter Burgess  (Vectis AS) - "Beyond the Eyepiece"

Graham Bryant (Hampshire AG/CfDS) - "Measuring Sky Quality by Light Meter"

The Vectis Astronomical Society would need names a week before the event to enable them to organise appropriate catering.

Please phone Richard Flux on his home number 01983 883063, or email the Vectis Secretary - John Smith on Johnwsmith.iow@tiscali.co.uk

Further information can be obtained from the Vectis AS website on: www.vectis-astro.org.uk/events2006.htm

Yes! It really is "events 2006"

JULY NIGHT SKY

Planets

Mercury becomes a morning object in July and may be seen around the 24th/25th/26th. It will be difficult to find in twilight as it rises only around an hour before the sun.

Venus at magnitude -4.0 is moving towards inferior conjunction and by the end of the month sets less than an hour after the sun. During July its phase becomes a thinner crescent whilst its apparent diameter increases.

Mars at magnitude 0.5 lies on the borders between Aries (the ram) and Taurus (the bull). It is still a morning object but by the end of the month it rises a little after midnight (BST) with its apparent diameter steadily increasing.

Jupiter Still lies in the constellation of Ophiuchus (the serpent bearer) at magnitude -2.5. Sadly it is never more than 17 above the horizon and by mid July sets around 02.00 BST. Binoculars or a very modest telescope will easily show the four brightest moons - Io, Europa Ganymede and Callisto.

Saturn in Leo (the lion) at magnitude 0.6 is difficult to observe and by the end of July will be lost in the glare of the sun. On July 1st Saturn and Venus are less than a degree apart in the sky.

Lunar Occultations

This is a lean month for lunar occultations with only two that fall within our normal criteria of being brighter than magnitude 7 and occurring before midnight (BST). As a result I've included a few that are slightly fainter or occur a little later. Times are all BST.

Date Time Star (SAO Catalogue) Constellation Magnitude Phase
Fri 20th July 22.25 SAO 138905 Virgo 7.3 DD
Sun 22nd July 22.16 SAO 158384 Virgo 7.7 DD
Tue 24th July 22.30 SAO 183794 Libra 7.0 DD
Thur 26th July 00.49 SAO 184602 Ophiucus 6.0 DD
Fri 27th July 22.06 SA0 187048 Sagittarius 6.8 DD

Meteors

Possibly the most watched meteor shower of the year is the Perseids which begin on July 23rd. Although there will be few meteors about so early in the shower, it is still worth keeping a watch if you have the time. I usually try to observe on every available clear night up until August 20th, which is generally considered to be the end, and in the past have been rewarded with a spectacular exploding Perseid.

In order to be comfortable it is best to lie on something like a sun lounger (foot end pointing a little east of north) with the head end slightly raised so that you can see as much sky as possible. Only a few meteors are seen very close to the radiant so a wide vista is important. I can remember watching the shower from Cornwall in 1999 (after the ill-fated eclipse) and some of the meteors almost reached the southern horizon behind us.

However, my own favourite way of observing the Perseids is to lie on the gently sloping roof of my bungalow on a platform that I made especially for the purpose. It consists of a long board that fixes around the chimney with a footrest to stop me sliding down the roof.

Observing in a group is fine and allows more of the sky to be covered. However, if like me you observe alone (who else is likely to want to lie on a bungalow roof at midnight) you realise that one of the biggest problems is falling asleep. After all it's dark and quiet and unless there is a lot of meteor activity I'm afraid it's all too easy to doze off up there. When I go back indoors after an observing session my wife always wants to know two things - how many meteors I saw and how many times I went to sleep!

ISS

Unfortunately, there are no passes of the ISS in July that occur before midnight. For more details log on to the web-site: www.heavens-above.com

Brian Mills

NASA SPACE PLACE

Chew on This

By Diane K. Fisher

The Mars robotic rovers, Spirit and Opportunity, are equipped with RATs, or Rock Abrasion Tools.  Their purpose is to abrade the surface patina off the Mars rocks so that the alpha x-ray spectrometer can analyze the minerals inside the rocks, rather than just on the surface.

But future robotic missions to Mars will be asked to go even further below the surface.  Scrapers and corers will gather rock samples of substantial size, that, in order to be analyzed by a spectrometer, will need to be crushed into a fine powder. 

Crushing rocks on Mars?  Now there's a problem that brings to mind a multitude of  possible approaches:  Whack them with a large hammer?  Squeeze them until they explode?  How about just chewing them up?  It was with this latter metaphor that the planetary instrument engineers struck pay dirt-so to speak.

Thanks to NASA's Planetary Instrument Definition and Development Program, a small group of NASA engineers came up with the Mars Rock Crusher.  Only six inches tall, it can chew the hardest rocks into a powder. 

The Mars Rock Crusher has two metal plates that work sort of like our jaws. One plate stays still, while the other plate moves. Rocks are dropped into the jaw between the two plates.  As one plate moves in and out (like a lower jaw), rocks are crushed between the two plates. The jaw opening is larger toward the top and smaller towards the bottom. So when larger rocks are crushed near the top, the pieces fall down into the narrower part of the jaw, where they are crushed again. This process repeats until the rock particles are small enough to fall through a slit where the two plates are closest.

Engineers have tested the Mars Rock Crusher with Earth rocks similar to those expected to be found on Mars. One kind of rock is hematite. The rusted iron in hematite and other rocks help give Mars its nickname "The Red Planet." Another kind of rock is magnetite, so-called because it is magnetic. Rocks made by volcanoes are called basalts. Some of the volcanoes on Mars may have produced basalts with a lot of a mineral called olivine. We call those olivine basalts, and the Rock Crusher chews them up nicely too.

Visit:  www.jpl.nasa.gov/technology to read the latest about other NASA technologies for exploring other planets and improving life on this one.

  This article was written by Diane K. Fisher and  provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

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CONTACTS

Chairman   John Vale-Taylor  pjvalet@tiscali.co.uk

Phil Berry  01892 783544 phil.berry@tiscali.co.uk

Treasurer  Mike Wyles  01892 542863 mikewyles@globalnet.co.uk

Publicity & Website  Michael Harte  01892 783292 michael@greenman.demon.co.uk

Newsletter Editor  Geoff Rathbone  01959 524727 Geoff@rathbone007.fsnet.co.uk

Any material for inclusion in the August Newsletter should be with the Editor by July 28th  2007

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