WADHURST ASTRONOMICAL SOCIETY

JANUARY NEWSLETTER 2006

INDEX: MEETINGS, OTHER NEWS, CONTACTS

A Very Prosperous New Year with lots of Clear Night Skies!

MEETINGS

THE DECEMBER MEETING

"Light on Light"

A talk given by Bob Seaney at the Society's meeting on 14th December 2005

      Bob Seaney is one of our own members and he began by telling us that he had been involved with lasers from the very early days and this had led to his greater understanding of the nature of light.  After asking if we thought light was a wave or a particle, it was apparent that a number of us were in doubt.

      Bob began by telling us what was known about light before 1905, when scientists used the prism, the colour spectrum, reflection and refraction to explain the nature of light as electromagnetic waves.  The analogy with waves in water was very strong and in 1855 Maxwell defined the electromagnetic wave equations assuming a medium of what was called Ether.

      The electron was discovered by J. Thompson in 1897 and six years later Max Planck proposed that energy exchanges took place in small steps called Quanta.  Then in 1905 in order to explain the photoelectric effect Einstein proposed that all electromagnetic radiation exists in the form of discrete Quanta or Photons.  Each Quanta has an associated frequency and the Photon frequency is proportional to its energy.

      In 1913 Neils Bohr proposed that the structure of the atom consisted of a nucleus surrounded by electrons that are confined to particular orbits.  Movement of electrons between orbits results in the emission or absorption of Photons.  Photons travel at 186,000 miles per second in a vacuum although this speed reduces by about 25% when it travels through glass.

      Bob showed on the diagram of an atom how a photon can transfer its energy to an electron, changing its orbit to an outer orbit and vice-versa when the electron gives up energy as it falls back to a lower orbit, thus creating a photon.

      The photon exhibits wave-like properties.  The creation of a photon results in the simultaneous creation of a "wave-function" that extends through all of space.  This function defines the probability of finding the photon at any point in space and until an attempt is made to detect the photon, it exists in a fuzzy state, somewhere!

      Bob explained that in a double-slit, no measurement can be made to determine through which slit the photon or electron went without destroying the double-slit interference pattern.

      The photon wave function lives in a universe of wave functions that are associated with all the other particles that make up space and time, each jostling with the other, nudging each other in and out of existence.

      A thought provoking experiment was suggested using the Calcium atom where photons could be created and deflected in opposite directions.  Each would have a spin opposite to the direction of the other.  Should anything cause one to change its spin, the other would also change its spin - wherever it was!

      We were presented with a few very interesting statistics:

Photon Energy:

Red Light Photon = 0.000000000000000000025 joules

Blue Light Photon = 0.00000000000000000005 joules

Number of photons equivalent to throwing a cricket ball 50 metres = 20,000,000,000,000,000,000

Number of photons coming from a zero magnitude star:

1)  Reaching the naked eye = 200,000 per second

2)  Collected by an 8-inch telescope = 330,000,000 per second.

      Bob left us with this remarkable sentence:  "The Universe is a very weird place.  Much of our future already exists just as our past is the future elsewhere..."

      He suggested a number of books worth reading to learn more about this fascinating subject:

"The Strange Theory of Light and Matter" in the QED Series by Richard Feynman 1990 published by Penguin 1990

"The Fabric of the Cosmos" by Brian Greene published by Penguin 2005

"Hyperspace" by Michio Kaku published by Oxford University Press 1990

"The End of Time" By Julian Barbour published by Weidfeld & Nicolson 1999

"Faster than the Speed of Light" by Joao Magueijo published by William Heinemann

This summary was written with reference to the speaker's notes which where a great asset - Editor.

THE ANNUAL GENERAL MEETING

A note from the Secretary

      Following Bob Seaney's excellent talk we were invited to a refreshment break consisting of warm sausage rolls and mince pies, tea and coffee.

      Next on the agenda came the Annual General Meeting.

      The Chairman Tim Bance reflected briefly on the past year's activities, which had been recorded in the Newsletters, circulated to members.  He then moved on to seek confirmation of Mike Wyles in the office of Treasurer, a duty he has successfully performed since February (when Jason Gardner was obliged to resign due to employment constraints).  This received unanimous approval with a show of hands as did the nomination of Phil Berry (seconded by Ian Reeves) to join the Committee.

      Phil had in fact agreed to be co-opted to the Committee at its 10 October 2005 meeting.  Tim went on to say that four Committee meetings had been held: 10 Jan; 11 Apr; 11 Jul and 10 October.  Subjects discussed included: public events, visits, rules, catering, change of venue and publicity.  The gist of which has been reported in our Newsletters.

      He highlighted two events: Herstmonceux in September, which attracted just one member.  However 10 members attended and enjoyed the visit organised by Ian King to the Hertford University Observatory on 21st October.

      The Chairman finally expressed his and other member's satisfaction with the move from a relatively expensive-to-hire and untidy drama studio to the Upper Room where there are attractive catering facilities.

      The Treasurer then presented the accounts for 2004/5 (which were with the Examiner) and delivered his report.

      These were approved and accepted.  The Hall hire figure did not bear the fees hitherto charged in advance for the months of November and December.  The Society remains in good health financially and subscriptions rates remain unchanged.

      Both the Web Master and the Editor sought feedback.  Members expressed their satisfaction with both the Website and the Newsletter.

      The Secretary then made a brief presentation highlighting the proposed changes to the Society's Constitution.  The December 2001 edition of the Constitution had been subject to comment and discussion from time to time during the year.  It had been redrafted to include several recommended constructive features.  These included the adoption of an accounting year starting 1st January (in place of the existing one of 1st November): Subscriptions to be paid within 3 months (instead of 8 months as hitherto): Assets on winding up to be donated to Hospice in the Weald (instead of Uplands C. T. College): Voting rights clarified: Opportunity to hold Extra Ordinary Meetings instead of waiting until an AGM.

      Draft copies of the revised Constitution were distributed to all members present to read, (these were largely as circulated with the November Newsletter) Adoption of the 3rd edition December 2005 Constitution was put to the vote and by a show of hands it was received with unanimous approval.

      The Chairman announced the dates of the 2006 Committee meetings:  9 January; 10 April; 10 July; 9 October and in the absence of any further business he closed the meeting at 2130.

Ian Reeves

JANUARY MEETING

Wednesday 18th January 2006 Dr John Lawrence gives an illustrated talk on "The History of the Telescope".  The meeting will take place in the Upper Room of the Methodist Church, Wadhurst High Street, beginning at 1930.

FUTURE MEETINGS

Wednesday 15th February 2006 Dr Martin Heath presents a talk with the intriguing title of  "The Habitability of the Red Planets".

Wednesday 15th March 2006 Martin Frey will talk about "Great Astronomical Blunders"

NEXT COMMITTEE MEETING

Committee members are reminded that there is to be a meeting in the Abergavenny Arms, Frant, starting at 2000 on Monday 9th January 2006.

As always, any member of the Society is very welcome to come along.

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OTHER NEWS

SUBSCRIPTIONS

Subscriptions became due on 1st November 2005 and any outstanding payments will be gladly received by Mike Wyles our Treasurer.  15 for members and 20 for joint members within a family.  Mike says that we now have 33 paid-up members so far which is excellent.

JANUARY NIGHT SKY

The Quandrantids meteor shower reaches a peak on January 3rd.  Their origin is in Bootes the herdsman which is low in the north-eastern night sky late in the evening.  There can be as many as 200 meteors an hour.  They are slow moving but rather faint and can produce tails from yellow to blue.  The shower is worth looking for although I have only been able to see them once.  This time the moon is well out of the way.  (Can't say the same for the clouds I'm afraid)

NASA SPACE PLACE

A New View of the Andromeda Galaxy

By Dr. Tony Phillips and Patrick L. Barry

      This is a good time of year to see the Andromeda galaxy.  When the sun sets and the sky fades to black, Andromeda materializes high in the eastern sky.  You can find it with your unaided eye. At first glance, it looks like a very dim, fuzzy comet, wider than the full moon.  Upon closer inspection through a backyard telescope-wow!  It's a beautiful spiral galaxy. 

      At a distance of "only" 2 million light-years, Andromeda is the nearest big galaxy to the Milky Way, and astronomers know it better than any other. The swirling shape of Andromeda is utterly familiar.

      Not anymore.  A space telescope named GALEX has captured a new and different view of Andromeda.  According to GALEX, Andromeda is not a spiral but a ring.

      GALEX is the "Galaxy Evolution Explorer," an ultraviolet telescope launched by NASA in 2003.  Its mission is to learn how galaxies are born and how they change with age.  GALEX's ability to see ultraviolet (UV) light is crucial; UV radiation comes from newborn stars, so UV images of galaxies reveal star birth-the central process of galaxy evolution.

      GALEX's sensitivity to UV is why Andromeda looks different.  To the human eye (or to an ordinary visible-light telescope), Andromeda remains its usual self: a vast whirlpool of stars, all ages and all sizes.  To GALEX, Andromeda is defined by its youngest, hottest stars. They are concentrated in the galaxy's core and scattered around a vast ring some 150,000 light years in diameter.  It's utterly unfamiliar.

      "Looking at familiar galaxies with a new wavelength, UV, allows us to get a better understanding of the processes affecting their evolution," says Samuel Boissier, a member of the GALEX team at the Observatories of the Carnegie Institution of Washington.

      Beyond Andromeda lies a whole universe of galaxies-spirals, ellipticals and irregulars, giants and dwarfs, each with its own surprising patterns of star formation.  To discover those patterns, GALEX has imaged hundreds of nearby galaxies.  Only a few, such as Andromeda, have been analysed in complete detail.  "We still have a lot of work to do," says Boissier, enthusiastically. 

      GALEX has photographed an even greater number of distant galaxies-"some as far away as 10 billion light-years," Boissier adds-to measure how the rate of new star formation has changed over the universe's long history.  Contained in those terabytes of data is our universe's "life story."  Unravelling it will keep scientists busy for years to come.

      For more about GALEX, visit www.galex.caltech.edu.  Kids can see how to make a galactic art project at spaceplace.nasa.gov/en/kids/galex/art.shtml.

      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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CONTACTS

Chairman          Tim Bance                   01732 832745

                                   timbance@hotmail.com

Secretary         Ian Reeves                        01892 784255

Treasurer         Mike Wyles                   01892 542863

                                    mikewyles@globalnet.co.uk

  Publicity         Michael Harte                       01892 783292

& Web site                    michael@greenman.demon.co.uk

  Editor            Geoff Rathbone                01959 524727

                  Geoff@rathbone007.fsnet.co.uk

Any material for inclusion in the February Newsletter should be with the Editor by January 30th  2006

 

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