WADHURST ASTRONOMICAL SOCIETY
MARCH NEWSLETTER 2008
INDEX: MEETINGS, OTHER NEWS, CONTACTS
The Committee are
respectfully reminded that there is a meeting of the Committee on Monday 31st of
March starting at 1930. Again, the
venue will be the Abergavenny Arms in Frant.
The Tim Bance
Tim Bance is a
long-standing member of the Society with a huge reputation for
telescoping-making and observing, and is also a past Chairman.
But he also restores furniture as well as having responsibility for the
huge gardens at The Place in the village of Leigh.
Recently his commitments have meant that he rarely has the opportunity to
our present Chairman, had the excellent idea of reporting an interview with Tim
illustrating it with slides. Sadly
Tim was unable to be present but John told a remarkable story of Tim's
background and activities.
Tim begins each
day at 0530 to deliver a paper-round! He
is also a qualified cricket umpire...
John began by
showing a number of slides taken in Tim's workshop in the old tack room of the
stables. A number of photographs
revealed the intricate cane work and chairs being restored to their former
glory. Another surprising item of
furniture was a dining table - that had once been a mortuary table!
John now turned
to Tim's achievements in the world of amateur astronomy, beginning by showing a
photograph of an 18-inch truss tube version of a Dobsonian built by Tim.
In 1997 Tim
became interested in astronomy and purchased a four-and-a-half-inch Tasco
reflecting telescope but was rather disappointed with its performance.
It was at about
this stage that he joined the Wadhurst Astronomical Society.
A member, Murray Barber, introduced him to the Norfolk Star Party where
many amateurs discussed equipment and observing techniques under clear night
Tim returned to
build his own 10-inch reflector tube employing circles and worm drives from
Beacon Hill and used a 6-inch reflector-guiding telescope.
The whole was housed in a 10' by 10' shed built in a walled garden.
This system was
used successfully for astro-photography.
For longer trips
Tim obtained a 5-inch refractor that enabled him to pursue his interest
that Tim had also built an 18-inch telescope for a friend, buying many of the
parts form the United States.
"bible" is "The Dobsonian Telescope" by David Kreige and
Richard Berry, a practical manual for building large aperture telescopes.
described the actual building of a Dobsonian, starting with the box frame at the
bottom with a Lazy Susan ball race and PCFE to provide an almost frictionless
support for the main tube.
A box that held
the main mirror was supported on either side by half-circles that slid on the
A view of the
underside of the mirror box showed the mounting points.
John later demonstrated a computer programme called PLOP that that gave
the exact points that should be used to reduce to a minimum the distorting
effects of the weight on the glass mirror.
beneath the mirror were provided to enable the final setting of the mirror when
lining up and collimating.
beneath the mirror was an electric fan whose purpose was to keep the mirror at a
"spider" holding the flat mirror, and the eyepiece was housed at the
other end of the telescope-tube, which was held in place with rods rather than a
solid tube so reducing the weight although these tubes were covered in
water-pipe cladding to reduce condensation.
Having taken care
to reduce the weight, it was still necessary to use diving weights to balance
used a Telrad eyepiece where the observer lines up a red spot with the celestial
object providing a very effective way of lining the telescope up with the object
to be observed.
Tim has also
visited star parties in the United States where they were using 24-inch and
balancing weights added to luggage excess, members of the star party buried them
beneath the surface of the site ready to be dug up again on their next visit.
concluded with an introduction to his own fascinating experiences in telescope
making, beginning with his first telescope which used a 6-inch mirror mounted in
an 8-inch flu pipe and using a gun-sight for the eyepiece.
The whole was set on an equatorial mount made of welded square section
He then briefly
described his engineering career mainly in optics.
He gave an interesting history of Vicker's Instruments from their
beginning in St. Dunstan's church on Fleet Street.
We were taken on
a breathtaking tour of the many aspects of John's work from microscopes and lens
making machines to the making of a beautiful Communion Table for a Lady Chapel
incorporating a cross with mounts for candles.
his talk by reminding members that the Society possesses a number of telescopes,
which are available for members to borrow.
One is a small Dobsonian and there is also the Ian Reeves Memorial 4-inch
refractor Konus telescope and tripod. The
refractor has an equatorial mount but does not have a drive.
It comes with its own travelling case.
March 2008 A welcome return of Konrad Malin-Smith with a talk about "The
Magellanic Clouds". This takes
us just outside our own galaxy to two of the Milky Way's closest neighbours in
begins at 1930 although members are invited to arrive anytime after 1900. This is a good time to exchange ideas and discuss problems.
The venue as
always is in the Upper Room of the Methodist Church at the east end of Wadhurst
Lower High Street, opposite Uplands College.
(For those with SatNav - the
Post code is TN5 6AX)
MEETINGS & EVENTS
April 2008 Greg Smye-Rumsby gives a talk he has entitled "Bits and
May 2008 Our own Brian Mills who contributes the excellent Sky Notes each
month is giving a talk about "Occultations".
During June: A visit is being arranged to visit the Great Transit Circle
at Greenwich Observatory. This will
be either Friday 13th or 20th of June. See
separate note below under Other News & Information.
Wednesday 18th June 2008 Because this is one of the shortest nights of the year, in recent years this has become a members' evening when we can bring telescopes, binoculars and other aids to amateur astronomy to chat about their use and discuss problems. There will also be a short video on an astronomical subject. More info. nearer our June meeting.
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THE GREAT TRANSIT CIRCLE AT GREENWICH
Once again, Phil
Berry has been working hard. He has
been in touch with Gilbert Satterthwaite who is willing to show a group round
the Great Transit Circle at the Greenwich Observatory at the Maritime Museum. The favoured date for the visit would be Friday 20th of June
2008, although a back-up date of Friday 13th of June has also been proposed.
reluctant to promise a date for us as they do not like booking up too far in
advance. However, Gilbert can not
see that there would be any reason why our visit on the 20th June would affect
the ROG but just in case we have a back up date of lucky Friday 13th of June.
At the March
meeting it is hoped that we can get some idea the number of members interested
in taking part. Members could also
show their interest by contacting either Phil Berry or Geoff Rathbone. (Contact details at the end of the Newsletter)
approximate itinerary would be:
10:15 Meet in car
park adjacent to Flamsteed House in Park.
10:30 Start tour
of Flamsteed House and the Octagon Room with a short stop for the Time Gallery.
then like to take us a chronological tour of instruments starting with
Flamsteed's (which are no longer in situ but Gilbert will show us where they
went), Halley's instruments and the developments up until the Airy instruments
including the main Airy Transit Telescope and how Gilbert himself used to use
the instrument. The breadth of this display is apparently unique in the world.
Gilbert will then
briefly show us the 28" Refractor in the main dome.
12:30 Break for
In the afternoon
we would be on our own and have free time to go back to the Time Galleries or go
to the Old Planetarium in the South Building where there is a large exhibition
on Space which can take quite a while to go around at our own pace.
After this we
could then meet up and have a group visit to the New Peter Harrison Planetarium
(accessed through the Old Planetarium South Building), which will be a bit
cheaper for entrance if we are still in sufficient numbers.
different shows during the day, these are:
Black Holes: The
other side of Infinity.
spectacular new show, discover the early universe, witness star birth and death
and the collision of galaxies and fly into a massive black hole lurking at the
hear of the Milky Way. Narrated by Liam Neeson.
Sky Tonight Live.
Presented live by
a Royal Observatory astronomer, you will be taken on a tour of what you can see
for yourself in tonight's night sky.
visually-stunning show looks at the lives of stars - how they are born, grow up,
grow old and die; how black-holes and pulsars form and how beautiful clouds of
glowing gas come into existence. Hosted by real astronomers who are available to
answer questions after the main programme. Gilbert thought that the
"Sky Tonight Live" was good as it was presented live by an astronomer.
It is at 16:00. It would be a
fitting conclusion to our visit.
note in the February Newsletter with regard to a Telescope Making Sub-Group
within the Society, some discussion took place at the February meeting.
It was suggested that any member interested in getting together to
explore setting up such a group is invited to come along to Angus MacDonald's
home in the Mayfield area during the evening of Wednesday the 12th of March.
The idea would be
to pool ideas and share skills and experiences.
No one needs to have special talents, just an interest.Can anyone
interested in coming please give me a call:
Geoff Rathbone on
FOR THE CURRENT YEAR
current session of the Society began on 1st of January.
Treasurer, Mike Wyles, is ready to accept subscriptions, which are the same as
previous years at £15 per member and £20 for two members in the same family.
prefers to receive a cheque payable to "Wadhurst Astronomical Society"
although he will willingly take cash. If
it is more convenient, subscriptions can be sent direct to him at:
M. Wyles, 31 Rowan Tree Road, Tunbridge Wells, Kent
At the monthly meetings, Phil Berry has introduced a clip-board with a sheet headed "Help List" intended for anyone asking advice. It has been used successfully and members are reminded to use the list as much as possible. It can be useful for discussion purposes as well as hopefully providing answers.
will be too close to the horizon to be easily observed this month.
lost in the glare of the Sun and is also not visible this month.
still easy to find in Gemini (the twins) close to the Auriga/Taurus/Orion
borders although its brightness and apparent size are both decreasing as we move
further apart. A large telescope will be needed to see any surface detail.
a morning object in Sagittarius (the archer) at magnitude -2.0. Unfortunately it
is (and will remain) low in the sky as seen from the UK. By the middle of the
month it rises at 03.45, about 2 hours before the Sun. Jupiter's four brightest
moons are easy binocular objects and their collective movements can be
fascinating to watch.
superbly placed for observation being visible throughout the night, setting just
before sunrise. It shines at magnitude +0.2 just below the "belly" of
Leo (the lion). Saturn's brightest moon (Titan) can be easily seen in a small
telescope at magnitude +7.0 on March 6th, 14th, 22nd and 30th.
On Friday 14th
March there will be a graze occultation, of a magnitude 6 star in the
constellation of Gemini, visible from an area that is reasonably close by. The
event occurs at around 21.57 hrs GMT when the star "grazes" past the
dark northern limb of the 54% illuminated waxing moon. Hopefully, it will
disappear and reappear as it passes between the lunar mountains and valleys as
seen from Earth. Timings of grazes help astronomers to build up and enhance
their knowledge of those areas around the moon's limb where these events occur.
The star in
question, SAO 77837, is known to be a double although it can't be seen in a
telescope as such. It is possible that the star may appear to fade and brighten
if only one element of the double is occulted. Observers located south of the
graze track would expect to see a disappearance followed a little later by a
re-appearance, possibly both on the dark limb depending on how far south of the
track they were. Observers north of the track would expect to see the star just
miss the moon's limb.
The tracks of
visibility of these events are very narrow and location of observers is critical
to trying to build up a profile of the limb. To this end we are hoping to
assemble a group of observers armed with suitable telescopes and stopwatches who
would be interested in taking part in such an enterprise and who would be
located at pre-determined positions perpendicular to the track. The nearest
passage of this track to Wadhurst is as it crosses the A28 roughly midway
between High Halden and Bethersden although before it reaches us it passes
through South London, Lullingstone Castle, Wateringbury and Headcorn.
or 01732 832691. I would suggest that if you are uncomfortable about being out alone at night in an unpopulated area then arrange to have a friend come with you. In any case it is always useful to have some help with you for when things go awry!
Phases of the Moon
|New||First Quarter||Full||Last Quarter|
|March 7th||March 14th||March 21st||March 29th|
Below are details of the most favourable passes of the ISS this month. The information given is for when it is at maximum altitude, so it is best to look a few minutes before this time. Full details of visibility can be found at:
|March||Magnitude||Time (GMT)||Max Altitude||Azimuth|
Don't forget - BST begins at 02.00 on Sunday March 30th.
one time or another, we've all stared at beautiful images of spiral galaxies,
daydreaming about the billions of stars and countless worlds they contain. What
mysteries-and even life forms-must lurk within those vast disks?
consider this: many of the galaxies you've seen are actually much larger than
they appear. NASA's Galaxy Evolution Explorer, a space telescope that
"sees" invisible, ultraviolet light, has revealed that roughly 20
percent of nearby galaxies have spiral arms that extend far beyond the galaxies'
apparent edges. Some of these galaxies are more than three times larger than
they appear in images taken by ordinary visible-light telescopes.
have been observing some of these galaxies for many, many years, and all that
time, there was a whole side to these galaxies that they simply couldn't
see," says Patrick Morrissey, an astronomer at Caltech in Pasadena,
California, who collaborates at JPL.
extended arms of these galaxies are too dim in visible light for most telescopes
to detect, but they emit a greater amount of UV light. Also, the cosmic
background is much darker at UV wavelengths than it is for visible light.
"Because the sky is essentially black in the UV, far-UV enables you to see
these very faint arms around the outsides of galaxies," Morrissey explains.
"invisible arms" are made of mostly young stars shining brightly at UV
wavelengths. Why UV? Because the stars are so hot. Young stars burn their
nuclear fuel with impetuous speed, making them hotter and bluer than older,
cooler stars such as the sun. (Think of a candle: blue flames are hotter than
red ones.) Ultraviolet is a sort of "ultra-blue" that reveals the
youngest, hottest stars of all.
the basic idea behind the Galaxy Evolution Explorer in the first place. By
observing the UV glow of young stars, we can see where star formation is
active," Morrissey says.
discovery of these extended arms provides fresh clues for scientists about how
some galaxies form and evolve, a hot question right now in astronomy. For
example, a burst of star formation so far from the galaxies' denser centres may
have started because of the gravity of neighbouring galaxies that passed too
close. But in many cases, the neighbouring galaxies have not themselves sprouted
extended arms, an observation that remains to be explained. The Galaxy Evolution
Explorer reveals one mystery after another!
much else is out there that we don't know about?" Morrissey asks. "It
makes you wonder."
the wonder by seeing for yourself some of these UV images at:
Chris Martin, principle scientist for Galaxy Evolution Explorer -or rather his
cartoon alter-ego-gives kids a great introduction to ultraviolet astronomy at:
This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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Chairman John Vale-Taylor
Phil Berry 01892 783544
Treasurer Mike Wyles 01892 542863
Publicity & Website Michael Harte 01892 783292Newsletter Editor Geoff Rathbone 01959 524727
Any material for inclusion in the March 2008 Newsletter should be with the Editor by March 28th 2008
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