WADHURST ASTRONOMICAL SOCIETY
As mentioned in the last newsletter, the meeting held on
June 12 had a change of speaker to the one advertised. The society was lucky
enough to have Alan Drummond attend the meeting and he gave a talk on the
subject of Open Clusters.
The talk started with an introduction to what an Open cluster actually is. They
can contain any number of stars from a few dozen to a few thousand, all stars in
a cluster will appear to move together and they will all have a common origin.
There are about 1000 known Open clusters, but there are very likely many more
that cannot be detected because of distance and luminosity. Alan bought along a
number of slides of various Open Clusters that can be seen, these included; The
Pleiades, M7 &
M6, The double
cluster in Perseus and the Hyades.
The stars that make up the familiar Plough shape in Ursa
Major are also part of an Open Cluster although it is very dispersed.
After the usual break for refreshments Alan continued the talk with a detailed look at measurements that can be made on individual stars in a Cluster. There are five measurements that can be made, Apparent Magnitude, Colour Index (b-v), Radial Velocity, Proper Motion and Parallax. From these measurements it is possible to plot a Hertzsprung-Russell diagram that enables the age of the cluster to be estimated. The distance can also be calculated by using the distance modulus. Alan also went into the formation of a Cluster and mentioned that many stars originally formed as part of a cluster. All clusters will disperse over time and so this is why not all stars are associated with a cluster.
Sean gave the society a talk on the subject of the Virgo supercluster.
The July meeting is to be held on Wednesday 10th at the
usual time of 7:30, in the drama studio at Uplands. The speaker this month will
be Andrew Robertson and the subject of the talk is Telescopes and Optics. One
aspect of Andrews's talk will be about the different types of telescope that are
available. It is hoped that the society will be able to display at least one of
each type on the evening, although we are still seeking owners of a Schmidt
Newtonian and a Schmidt Cassegrain who are willing to bring their telescope to
the meeting. If you have one of these and are willing to bring it to the July
meeting please let the Editor know in advance if possible.
This meeting will be the last one before the usual summer break during August. The next meeting will be held on Wednesday 11 September. We will of course be having the summer Barbeque, further details will be in the next newsletter.
The Society supported this event held on June 22, with a
team of nine accompanied by eight telescopes, a sun scope, a display of some
first class photographs and a raffle ticket drum. Excellent sun projections were
conducted using as many as four instruments at any one time. These were made the
more interesting by the mixture of whisps and small lumps of cloud that hurried
across a sunny sky. The breeze experienced at ground level was in the region of
force 5. It was gratifying that so many visitors came for a viewing. A display
is expected to be made at the July meeting of the 19 unique Sun eclipse pictures
produced by Peter Prince. They could well be of value to the fashion trade! Some
100 or so drops of rain fell in two light sprinklings of 30 seconds each. These
turned the excellent images into unusual designs of interest and no small
amusement to the public. They may well have stimulated a late flurry of activity
in the sale of tickets to our raffle. Members will be pleased to learn that a
young boy from Speldhurst won the Tasco Refractor and he intends to make use of
it. The other prizes were a one year membership to WAS and a Constellation
Umbrella. The sale of 194 tickets gives some indication of the interest shown in
It was well worth the effort to have participated in this fete, which was certainly well organised. Thanks to Tim for lining us up for it.
The team consisted of: Tim Bance, Valerie and Murray Barber; Thelma and Duncan Goulding; Peter Prince, Ian Reeves, Sean Tampsett and Mike Wyles. All of whom got slightly sunburnt.
Chairman: Murray R. Barber 01892 654618 firstname.lastname@example.org
Secretary: Tim Bance 01732 832745 email@example.com
Treasurer: Ian Reeves 01892 784255
Editor: Peter Bamblett 01732 368656 firstname.lastname@example.org
Web site: Rob Cray email@example.com
Publicity: Michael Harte 01892 783292 firstname.lastname@example.org
Dir. of Obs.: Sean Tampsett 01892 667092 email@example.com
Librarian: Joan Grace 01892 783721
Custodian of Equipment: Peter Prince 01892 836284
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