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2006 Meetings

13th December

"The Christmas Star" by Dr. Percy Seymour, retired Principal Lecturer in Astronomy at The University of Plymouth

WHAT WAS THE STAR OF BETHLEHEM?

 Introduction 

25th December was the day on which there was a noticeable increase in day length, so, even before the birth of Christ, it was celebrated as the day of the return of the SUN-GOD from the south. 

The early Christian Church adopted this as the day on which Christ was born.

There were errors in the calendar.  Herod’s death was marked by an eclipse of the Moon.  This could have been the one of 10 January 1BC or the one of 13 March 4BC.  Both of these would put the birth of Christ before the normally accepted date of 1AD.

Assuming ‘The Star’ was an actual astronomical event.  The Magi were astrologers.  Quote from Patrick Moore:

“We must always bear in mind the purely astrological significance of the star, and we must accept that the wise men were astrologers first and foremost.  And if the star really existed its astrological implications must have been profound.”

I believe that to do research into THE STAR we must look at all possible astronomical events that occurred around the time of Christ’s birth, and then consider how these events might have been interpreted by the magi-astrologers.

Aristotle’s Universe and the Philosophy of Ancient Astrology

In Aristotle’s theory, the universe consisted of a series of concentric spheres, surrounding the spherical Earth.  There were seven transparent spheres, and to each one of these was attached a planet (the Sun and Moon were also considered to be planets at this stage).  Below the sphere of the Moon we had the spheres of fire, air, water and Earth.  In these sub-lunar spheres there could be change, corruption and decay, but in the spheres above the Moon, there could be no permanent change; everything had to be based on cycles of change.  Ancient astrologers believed that the spheres below the Moon were under the control of the spheres above the Moon.  How could decay and corruption arise if this was the case?  This was because of free-will.  Although the regular movements of the planets gave a direction to human behaviour we were free to act as we wished – we could ignore the messages from the cosmos.

Could the STAR have been Halley’s Comet?

Comets were irregular visitors to the skies, and this meant they had to be in the sphere below the Moon.  It was Edmund Halley (2nd Astronomer Royal at Greenwich) who discovered that some comets were periodic, but mostly they had very long periods.  The comet that bears his name has a period of 76 years and it was seen in 12 BC.  Since astrology was based on the predictable movements of the planets, comets were not included in their schemes.

Could the star have been a Nova

A nova is not a new star, but a relatively faint star, which, over a period of days, suddenly increases its brightness and then, over a period of months, or even years, it gradually fades away.  Generally these brightness increases are non-periodic and unpredictable.  Such behaviour was not allowed in Aristotle’s theory, because the stars were the region of perfection.

Conjunctions and Occultations

A conjunction between two planets occurs when two planets overtake each other on the highway of the sky, which is called the zodiac.  Over the last 400 years conjunctions between Saturn and Jupiter have been the most popular explanation for the star.  However, in the last twenty years conjunctions between other planets have also joined the list of possibilities.

A new and different possibility is that has emerged in the last ten years is that THE STAR was an occultation of the planet Jupiter by the moon.  An occultation is when the moon (or a planet) passes in front of a star (or another planet).  In the second half of the talk these various theories were put forward

8th November,

"The Dorset Trailway" by Giles Nicholson, Senior Ranger of Dorset Countryside Commission

Giles explained how, since the old Somerset and Dorset Railway line closed in 1966, the track has fallen into disrepair and become overgrown.  The North Dorset Trailway Project is to provide a two and a half metre wide multipurpose pathway along the old railway line for use by a wide variety of users such as walkers, cyclists, horse riders and the less able.

 Already five sections of the Trailway, totalling 8 km/ 5 miles are open to the public.  In a few weeks the first of the Project’s restored bridges across the River Stour will be opened at Fiddleford, allowing further access to some of North Dorset’s spectacular countryside.

 Many fascinating facts were revealed during the talk.  The virgin soil beside the old railway supports many old varieties of fruit trees, many of which are no longer available since the old orchards have been grubbed up.  The trees growing today sprang up after rail passengers jettisoned apple cores and plum stones through the steam train windows!  Apparently delicious apples, plums, greengages and the like are growing freely.

The wide expanses of embankment are now home to a rich variety of wildlife.  Hopefully some sections may become Nature Reserves or Sites of Scientific Interest.

10th October 2006 

"The Science of Brewing" by Toby Heasman, Brewery Manager of Hall and Woodhouse,

This discussed the role of biochemistry of the raw materials, the sequential stages of the brewing process and how these are controlled to produce the different beers.  The talk was designed to  appeal to the consumer, the amateur enthusiast and the scientist.  The deeper biochemical structures were accompanied by lighter hearted pictures and beer descriptions.

13th September 2006

"Sea Level Changes on the Jurassic Coast"  by Professor Chris Wilson

The conclusions seemed to be that there are so many factors affecting sea levels, from gravity to global warming, from undersea volcanoes to melting ice caps, that there is no simple answer.  There is just evidence that change has happened many times in the past and is still continuing today!

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