The September HAS meeting was again well attended, perhaps lured by the interesting sounding talk on "Physics of the Extraordinary". First of all, however, Eric Walker, our Secretary, read out a large number of notices.

 

• Seeing Stars  "The Pole Star and The Dragon" by Rhona Fraser will be published in 5 September’s Inverness Courier and later on our website.

• Kid’s stuff  The children’s subgroup first meeting was held this evening. Pauline and Trina plan to continue this group during the winter, at 7 p.m. at The Green House. Please contact them if you are interested.

• Next Meeting  will be on the 7th October, with a change from the advertised programme,when Maarten de Vries will be speaking about "Messing Around With Messiers" , followed after tea break,by a breakout group (to be decided) or, weather permitting, an observing session at the JSL Observatory. Following this announcement, John Gilmour, our chairman, notified the members of a future significant increase in the price of meetings at the Green House, this being due to us requiring the security firm to lock up at the end of the evening. Up until now John has been doing this for us as a Green House employee but his company has recently gone into liquidation. He mentioned the possibility of moving to the visitors centre at Culloden and asked member’s views. A significant minority held strong opinions against any proposal to move to the Culloden, leading John to encourage members to think of other locations for themonthly society meetings in order to contain our costs.

• HAS book sale In aid of observatory funds, will be held at the October meeting. Bring your unwanted books, astronomical or not. DVDs/Videos are also welcome. Remember to bring extra pennies too...as there are bound to be bargains available!!! All in a good cause!

• Tesco bag packing day  We need 20-22 volunteers to help on Saturday, November 22nd. Please contact Pauline.

• Mobile phones/printer cartridges  can be recycled in aid of funds. Please contact Eric.

• HAS "BAA" subgroups  The section "leaders"will be contacted by Eric to arrange a meeting to discuss the way forward prior to establishing them within the Society.

• Open day / Open Doors  This year we will be taking part in the Highland Council Open Doors scheme. On Saturday, 6th September, we will have our Open day in Eastgate Centre from 0930-1530 , then JSL observing for the public in the evening. Post meeting note - This proved to be a great success, despite the cloudy skies, with over 100 people coming to the observatory at night.

• Christmas dinner / potential Solar Eclipse Cruise  If interested in either of these please contact John Gilmour directly or add your name to the list at the Society meetings. If there is sufficient interest in the longest eclipse of the Century (6.5 minutes) on the 22nd of July 2009 , we may organise a cruise trip to China.

• JSL Observatory plaque  If you haven’t yet received your certificate commemorating your name on, please contact John Gilmour directly or see him at the monthly meetings.

• Trip to the Royal Observatory, Edinburgh  Members interested in an outing to the ROE in either October or November should add there name to the list at the next meeting, indicating which Saturdays they prefer, and/or can’t make or contact Pat Williams.

• BAA Variable Star Section  will be at the Edinburgh ROE on the 18th October from 1030-1600h. A charge of £10, will include lunch. If interested contact Rhona Fraser.

• Members first light star party  was held on Friday 29th of August at the JSL Observatory. Many thanks to all of our members, who turned out, bringing food and drink and generally making the event a night to remember. Once clouds had dissipated, the views from the new telescope were truly remarkable.

• JSL Opening Day  A CD for £5 in aid of observatory funds, showing photographs of the building phase, the opening day, and copies of various press/website articles as well as John’s interview on Highland Cafe will be available for sale soon.

• Astronomy Now  features the Observatory in its September edition.

• The Press & Journal  newspaper featured an article on HAS member Craig Ferguson mentioning his love of astronomy, and his enthusiasm for the new facility.

• Reul-Chuirt  A DVD collection of all the programmes will be available from the HAS library to borrow. We were featured on the third programme in the Gaelic (archeo)astronomy series.

• ‘4000 Years of Astronomy in the Highlands’  will be a mini festival run in conjunction with NTS at Culloden, in March next year. We have applied for Highland 2007 Legacy funding for this event and will know the outcome around September 23rd.

• Aberdeen University  is launching a series of courses including astronomy.Information will be available at the monthly meetings.

• And finally ….. Stargazey Pie will be made available to all members, whether they attended the monthly meeting or not, either by e-mail or post.

 

 

The Main Event
'Physics of the Extraordinary' by Colin Donaldson, Glasgow University

Colin is currently attending Glasgow University and is well known to us as a former member of the club. He enthusiastically explained information he had been taught at university. Bearing in mind, this involved Einstein’s theories of relativity, he had a hard task ahead. However, it was ably performed by concise, and almost non- mathematical means.

Colin began by drawing a distinction between what he thought was ordinary physics i.e. Newton’s laws of Motion, energy output of a star and the usual every day boring stuff and extraordinary physics i.e. sounds like it is from Star Trek, the relativistic effects of light near the surface of a gravitationally strong singularity and absurd explanations for phenomena, made up by theoretical astrophysicists sitting in a room.

The physics of the extraordinary all boils down to the properties of light. Light is both a particle and a wave, which is often difficult to comprehend. The particle form comes in small packets called photons, each with a zero rest mass, which was first explained by Einstein in the photoelectric effect. Because a photon has a zero rest mass, it will travel at the speed of light (300,000,000 m/s) in a vacuum.

The wave form can be proven by directing light through two slits. As the wavesof light pass through they cause interference, which can either be constructive, when two peaks interact producing bright light or destructive, when two troughs come together producing a dark fringe. Light occurs in a wide range of wavelengths from the very long radio waves through microwave, infrared, visible, ultraviolet, X-rays to the very short Gamma rays.

Colin then went on to explain Einstein’s Special theory of Relativity which states that the laws of physics hold in all frames of reference and the speed of light is constant in all frames of reference. Before Einstein, most physicists believed that light waves propagated through a medium called "ether". The Michelson-Morley experiment was set up to prove the existence of this ether,as the speed of light would be different in different directions. This used the wave property of light ( i.e. interference) to measure any difference in the speed of light in different directions. However, the experiment failed to see any difference in the wave patterns from different directions, implying despite, its orbital motion that the earth was at rest in the ether. Hence, Einstein postulated that the speed of light is the same in all inertia of frames no matter what velocity these initial frames move with reference to each other. The ether did not exist. This experiment is known as the most significant negative result ever performed!

At this point, Colin produced some mathematical equations. These were not too complicated and involved the square root of minus one ... an imaginarynumber! To explain Einstein’s results, a moving object is shortened in the direction of motion, moving clocks run slower, and it is impossible to move faster than the speed of light, as it requires infinite energy. Can an object go faster than the speed of light? In theory, it can, although you would not be able to obtainany useful information from it. Obviously, this has important ramifications for space travel. (Star Trek’s Warp Drive/Hyperspace?) Time contraction has been proved by experiments with Cosmic Ray Muons.

What useful effects come from Einstein’s theories? General relativity, states that photons travel along lines in space and time, which can be distorted by a large mass. This effect is called gravitational lensing. Light from a background object is bent around a large foreground mass producing a series of arcs called Einstein rings. These have been seen and can be used to detect massive objects such as black holes, neutron stars, or even dark matter. Ripples in thecurvature of space-time, known as a gravitational waves are another prediction from General Relativity. These waves might be produced by violent acceleration of mass e.g. during the formation of black holes or neutron star binary collisions and are currently the subject of much research. Their detection involves measuring tiny changes in the lengths of objects ,a difficult task requiring large arrays all over the world and perhaps in the future in space.

 

Next Time

The next meeting will be at the Green House on Tuesday 7th October at 19.30h when Maarten de Vries will be "Messing Around With Messiers". Maarten is well known for his enthusiasm and expertise and has recently set up the ‘Messier Challenge’ for Society members. A talk not to be missed especially if you are taking up his challenge! Enjoy the encroaching darkness, and remember to drop by the message board on the website if you want to ask questions or simply pass on your observations. http://www.spacegazer.com/forum 

Dark Skies,

Rhona Fraser