SEPTEMBER NEWSLETTER 2004
INDEX: MEETINGS, OTHER NEWS, CONTACTS
LAST MEETING
Recent innovations in mobile
planetariums
Most
members of the Society know that Murray Barber and Valerie his wife give many
talks to Schools and other organisations and have done so for many years. He owns his own sixteen-foot high
inflatable planetarium, which only just fitted into the Drama Studio at Uplands
College. The Dome had already been
prepared before we arrived and Murray welcomed members and gave a brief
introduction into how the mobile planetarium came into being.
About
twenty years ago Phil Sadler in Massachusetts, USA, took his son to see a lecture
in a local Planetarium Theatre. When
they got home his son asked if it was possible to recreate the theatre.
Phil thought about this and actually constructed his own planetarium,
which after a lot of improvementsbecame a workable dome and projector.
The problem making a practicable projector was overcome by using black
film in the form of a topped cylinder.
He then created the stars on the surface of the film. He used a very tiny bulb with a filament
only 2 mm in length to obtain the definition. To project the stars in their relative
correct positions on the inside of the dome was quite an achievement and he
used a computer to position the night-sky on the drum. Projection through a sphere would have
been far easier but less practical.
Murray
also pointed out that on the original drum, there was no Milky Way.
We were
then invited into the dome and all managed to sit quite comfortably round the
perimeter in one group. This part
of the evening was divided into two with a coffee break in between.
Murray
described the cylinder and how the planets were projected through separate lenses
enabling their positions in the night sky to be very precise. The positions of the sun and moon were
limited to twelve locations simply because of room within the pattern of stars
on the cylinder's surface. One
surprising fact was that it was almost impossible to detect the junction of
the side of the cylinder and the "lid" in the spread of projected stars.
With
atmospheric background music the lights dimmed and we were presented with the
cloudless night sky as it would be that night. Although very clear, some of the
brighter objects close to the horizon tended to be a little distorted. Murray took us on an enthusiastic time
travel through the following twenty-four hours, describing some of the star
patterns such as the Summer Triangle formed by Deneb,Vega and Altair, and the
square of Pegasus using the stars as a guide to other interesting objects.
During
our coffee break the Projector was changed to the new FibreArc light source
projector and at the start of this part of the evening, the clarity and
sharpness of the night sky was very impressive, and with the new Multilens drum
we were able to see the Milky Way in its entirety as seen from the earth. The artwork for this had been suggested
and produced by Murray himself and is now used by the manufacturers.
Murray
then asked if any member had any objects they would like to have pointed out,
and with his usual thoroughness not only did he indicate the objects but also
gave guidelines as to how to find them, such as M1 the Crab Nebula.
Finally
we were shown a separate drum that gave the relative sizes of the sun and
planets and a surprising amount of statistics and detail. Using this drum Murray and Valerie were
able to blank out irrelevant parts depending on the age level of the audience
they were talking to.
It was
a very interesting evening and it was particularly revealing to compare the old
projection method with the new.
NEXT MEETING
The next meeting of the Wadhurst
Astronomical Society will be on Wednesday 15th September when the speaker will
be Jerry Workman, who has spoken to us before in January 2002 when his subject
on that occasion was "Mars Revisited".
As
usual, the meeting will be held in the Drama Studio at Uplands College. The doors open at 7.15 and the meeting
starts at 7.30 prompt.
The
Federation of Astronomical Societies (FAS) is to hold a convention on 2nd
October 2004 at the Institute of Astronomy, Madingley Road, Cambridge.
The
doors open at 8.30 am and there will be various trade stands and society
displays.
Confirmed speakers include
Professor Douglas Gough, Dr. Paul Murdin, Guy Hurst and Dr. Cathie Clark.
On the
day, tickets will cost £8, but advanced tickets may be obtained at £7 and are
available from Stan Waterman, "Amadeus House" Temple End, Charlton, Hitchin,
Herts. SG4 7TE. Telephone: 01462 433912.
email:
ticket.sales@fedastro.org.uk
Further
information can be obtained from the internet at http://www.fedastro.org.uk/
A NOTE FROM THE TREASURER
Our
financial year closes on the 31st October 2004. Shortly after that all members of the
Society have to elect a committee for the next year. Half of the present team will be standing
down while the other half is looking forward to welcoming 3 or 4 others from
the 41 members yet to take their turn, for up to a couple of years on the committee.
Under paragraph 5 of our Constitution "Any member shall be able to nominate
other members for election subject to the nomination being seconded."
Please send your nominations in to one of the Secretaries, Doug Biswell
or Steve Camp. If you are not on
the net then send them to Ian Reeves.
Do so now, so that election preparations can be made well ahead of the
annual meeting. Our contact numbers
are at the foot of this Newsletter. If
you cannot remember someone's full name describe him or her to the Treasurer
and he will endeavour to help. His
address is: Ian Reeves, WAS Treasurer, Broadwater Lodge, Stone Cross Road, Wadhurst,
East Sussex. TN5 6LR.
The Society
is in funds. It has not had to
touch reserves this year and might do better than break even by the end of our
year. More good news, the committee
does not see any reason at the moment for increasing subscription rates.
Chairman: Vacant Position
Secretaries: Steve Camp
steve.camp52@btopenworld.com
Doug Biswell
dougrbiswell@aol.com
Treasurer: Ian
Reeves 01892 784255
Membership Sec: Joan Grace 01892 783721
Editor:
Geoff Rathbone 01959 524727
Geoff@rathbone007.fsnet.co.uk
Publicity & Web Site: Michael
Harte
01892 783292
michael@greenman.demon.co.uk
Dir.
of Obs: Sean Tampsett 01892 667092
sean_tampsett@hotmail.com
Any material for inclusion
in the October Newsletter should be with the Editor by September 30th 2004