www.caa-cya .org

CAMBRIDGE ASTRONOMICAL ASSOCIATION

Newsletter 200 Sept - Oct 2019Registered Charity No. 800782

Cover CAA-CYA at the “Apollo film” at the IMAX ……. 1Chairman’s comments Public Observing prep & Start ……… 229th Oct 2019 CAA special visit to the Whipple Museum … 227th Sept Dr. Julian Onions “Cold Dark Matter” ……. 318th Oct 2019 Paul Fellows “Hawking & Edge of Physics” ... 3Review by R White on the excellent Antikythera MechanismLecture by John Lancashire ….….….….….……….………… 4My Messier Marathon by David Davies …………………….. 5Finding the Angle of the Sun’s Rays John Whitehead …… 6

CAPELLACAPELLA

CAA & CYA Who’s who contact info. P10

This Issue’s Contents

Continued story of JW’s experiment on Earth’s Axial tilt ….. 711th Oct CAA 60 Star Party & Photograph competition … 8Diary Dates See CAA-CYA Website for more detail ………. 9Display Table, Editors notes & Loan Telescopes …..….….… 9CYA 7-11 group Sat 28th Sept Local Group of Galaxies …. 10CYA 7-11 group Sat 26th Oct Mini Rockets .………………. 1011+ year old Meetings - Parents are always welcome ……..Monday 2nd Sept Don’t forget thje Inverse Square Law .. 10Monday 7th Oct Galileo ………………………………....…. 10

Everyone waiting to see the newly discovered 70mm NASAarchived film of the “Apollo 11 Moon landing mission”.

David Davies waiting at the barpossibly for a quick refresher.

Brian checking in Richard Whiteand guest, plus John Whitehead.

The “Apollo 11 NASA Moon landing and recovery” film at the IMAXin Cambridge where the CAA-CYA had a special viewing of thestaggering full 70mm production. It included video from every viewpointand also showed us some recently found and recovered 70mm live footage.

Lower Photos by Paul Fellows

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Chairman’s Comments

Hello Everyone, and welcome back to the start of a new stargazing season after our short summer break. We ended beforethe break with a wonderful visit to the IMAX in Cambridge to see the awesome Apollo 11 film with its jaw-dropping footageof the mission. What a way to bring things to a close for the summer! Looking ahead, we now have to get ready and bring allthe public observing gear back on line, and if anyone wants to join us for this, and learn about how to operate the equipment,then you would be most welcome. We are also back to full speed with the CYA 11+ program again. Now - and I'd just liketo remind you that this is open to all adults as well - so if you need a fix of astronomy on a Monday evening, once a month,then this could be for you.

Paul Fellows

Cambridge Astronomical Association& Cambridge Young Astronomers

As mentioned in Paul’s “Chairman’s Comments” (above), Brian brought this up at the presentation on the 16th this month.This is your opportunity to come and help us before the public observing sessions begin in October (see below). There willbe practice sessions during September without the public present. This give us a chance to check everything works after thesummer break, make improvements, and train new helpers. If you would like to come along to see what happens and possiblyoffer your help, please come along to the Northumberland lawn at 7.00pm. For further information please contact PaulFellows.

Public Observing Wednesdays from October 2019 to March 2020

On Wednesdays from October 2nd to the end of March, in conjunction with the IoA we organise and run the Public Observing atthe Institute of Astronomy, Madingley Road, Cambridge. Doors open at 7.00 pm, for a lecture from one of the IoA team at 7:15.See the website for the list of speakers. Observing starts at 8.00pm, if clear skies permit. To see if observing is on, please ring theInstitute after 5.00pm on 01223 337548 and listen to the recorded message. If it is cloudy, there is usually a cup of tea to warm usup, and sometimes other treats such as a tour of the telescopes. You will usually get the chance to look through both the 12-inchNorthumberland Refractor (which is 20 feet long!) and its smaller companion, the 8-inch Thorrowgood. Outside on the lawn, wewill have three other telescopes, each equipped with electronic cameras, and will be projecting the images from them live ,onto twohuge screens. The CAA team will be there operating these, and talking you through what we manage to track down and show.

Public Observing Starts in OctoberSetting up and preparing for next month is starting on Wednesday 4th September

To coincide with the 75th anniversary of the founding donation of the Whipple Museum we are have atalk and guided tour of the Whipple Museum by Dr Joshua Nall. As well as the special exhibition theywill be bringing some objects and instruments out of their large reserve collection for us to look at.

Josh joined the Whipple Museum in 2013, after gaining his PhD on the History and Philosophy ofScience here in Cambridge. His research focuses on mass media and material culture of the physicalsciences after 1800. He has curated a variety of exhibitions and displays, including on globes, scienceand industry in Cambridge, and most recently, the most curious and controversial objects lurking inthe Whipple Museum's stores.

No need to book. Please arrive at the back door of the museum just before 7.00pm. Access is through the new museum’s siteentrance, Downing Street. Walk through the arch past the Museum of Zoology and turn left and then left again. There willalso be somebody there to direct you.

CAA special visit to the Whipple MuseumTuesday 29th October 2019 at 7pm

Museum guide Dr Joshua Nall

These speaker meetings will be in the Hoyle building of the Institute of Astronomy, Madingley Road,Cambridge. Doors will open at 7:30 p.m. and the talks will begin at 8:00 p.m. For security reasons, entry will notbe possible after 8:10 p.m. As usual, the library will be open before and after the lecture and refreshments will beavailable after the lecture. These meeting are free to members. Non-members are charged £1.

Speaker Meetings“Cold Dark Matter”

Friday 27th September 2019Start time: 20:00

Speaker: Dr. Julian Onions

“Hawking and the Edge of Physics”Friday 18th October 2019

Start time: 20:00Speaker: Paul Fellows

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The notion of a 'Dark Star' began with the calculations by John Mitchel who realized thatNewton's laws of gravity and the finite nature of the speed of light could lead to stars whichcould not shine. We now call such monsters 'Black Holes'

In this lecture, Paul will then move on to look at how Einstein revealed that gravity is the resultof the curving of space and time, and the implications that nothing could ever escape from ablack hole. We will then look at how this theoretical picture of a one-way trapdoor was theone which troubled the young researcher Steven Hawking.

Stephen's response was his 1976 paper which was the first to bring together three main pillarsof scientific theory, Quantum Mechanics, General Relativity and Thermodynamics - a featwhich had defeated Einstein and many others for 60 years.

The paper shocked the entire scientific world and began Stephen's rise to world fame.

Paul will explain the basis of the problems, and how Stephen brought the ideas from these different theories to solve a fundamentalaspect of the behaviour of Black Holes.

In Stephen's own words "Black Holes ain’t so Black".

Paul is Chairman of the Cambridge Astronomical Society and a keen amateur astronomer, having built his first telescope in1975. He now operates his own private observatory and takes many astronomical images of both deep sky and solar systemobjects. He studied at Emmanuel College Cambridge, from which he has an MA in Natural Sciences and a post-graduate Diplomain Computer Science. He is an elected Fellow of both the Royal Astronomical Society and the Institute of Engineering andTechnology, and RAS Fellow to Cunard Line as well as a part-time advisor and board member of a number of software andelectronics design companies in the Cambridge area.

We hear a lot about dark matter in astronomy. Some people consider it a fudge.

In this talk we'll go through the evidence for dark matter and the history of it, and answerthe questions the title brings up.

No particular prior knowledge is assumed so the talk should be enjoyed by all!

Julian is a post-doctural researcher at Nottingham University and works with computersimulations of large fractions of the universe to understand trends in galaxy formation andevolution. He also investigates the tools that help us form and analyse such simulations suchas halo finders, tree builders and semi-analytic models.

A schematic of the entire Antikythera

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Speaker John Lancashire Bsc ACA

“Under the Hood of the Antikythera Mechanism”

19th July 2019 review by Richard White

Member’s Contribution

Well what a fantastic seminar this was. We were all enthralled by John for showing us the history and new redevelopment ofthe Antikythera device. At the end of the talk, he showed a full working model that he had built after years of research.

The Antikythera device. It was found on a typical 27mtr Romanmerchant ship hat had sunk somewhere around 70BC BetweenKythira and Crete. It was heavily laden with cargo including manyvery fine bronzes. It was also carrying the mysterious Antikytheradevice. It took over 10 years to piece it together from the 80+chunks and fragments. When it was put together it was put ondisplay in the National Archaeological Museum of Greece. AMRPwere able to see inside the layers using X-ray systems. In 2005

they discovered it had layers of fine tooth cogs and 2 arc scale grids.

John explained that after a huge amount of work, they assessed it was used to determine at least five particular astronomicalevents with precision. Parts of the device were built in bronze in 150BC

They discovered: 1 - A Calendar Computer with Lunar Phase, 2 - A Saros dial (Eclipse Predictor), 3 - The Lunar Anomaly correction (tocalculate the Lunar Epicyclic). 4 - The Inferior Planet cycles, i.e. Mercury, Venus and the “True Sun” 5 - The Superior Planets Mars, Jupiterand Saturn. But also 6 -The Parapegma, The Olympic games dial which started in 776BC 7 - Setting the Egyptian Calendar, and 8 -The Moon Ball assembly.

John went on to explain that there have been several attempts to build a replica machine, the first of which seems to have been attemptedbetween 1995 – 2005AD., and resulted in 4-5 papers. Another attempt after CT Scanning the device by AMRP was between 2006 -2012 that resulted in 10-12 papers written and published. A new version created by John our speaker was initially based on the AMRPversion but at a higher complexity. It ended up needing 3D printed gear wheels and calibration for use in our current era.

It is thought that the Babylonians were the first true astronomers. They observedthe duration, colour, and direction of each eclipse, apparently both Lunar and Solar.They called it the Saros. Our Zodiacal Charts started in approximately 450BC butbefore that the Babylonians had created comprehensive records of eclipseobservations on 4.3cm tablets. The Chaldeans worked out that there were 12 signsin the year cycle, and so the Hebrew equivalent soon appeared. There were ancientnames for the 13 Arabic months. It was the Greeks who worked out 19 solar yearscycles averaging out at 365.25 days. This made the calculation of sidereal months.So in 19 years, the Moon passes through 235 Synodic Months - 254 SiderealMonths when at is back at the first point again.

All this mathematics came about by detailed astronomical observations withouttelescopes, cameras, accurate clocks, computers, logarithms and calculus. Whoever created the Antikythera had no way to establishtime or distant angles. But they were able to create a metonic clock. It determined five main events recorded. The Saros dial depictedfine text and symbols to mark the Saros cycle over 223 months, and a second dial showing 669 Synodic months.

Babylonian Lunisolar Tablet

Roman Merchant Vessel

John showed us the pin and slot mechanism adjusting the sidereal position of theMoon according to Hipparchus theory. Incredibly one full turn of a particular cogwould turn the cog with a slot in it every 8.883 years. The whole Antikythera machineas apparent has 34 gears and 2,074 gear teeth.

Demonstration of the working model

The Antikithera device

It has however been decided thatthe inner planets would also havebeen surmounted on the face ofthe device featuring a pin andslot mechanisms making 55gears and individually hand cut3.142 teeth. An incredible bit ofpainstaking engineering that is

thought to date back 2,089 years by someone completely unknown to us today.For anyone interested in having it on display at home, John has made a workingclockwork style replica of the device including the inner planet mechanism.

Member’s Contributions5

My Messier Marathon

Story and Photo Images by David Davies

I first took an interest in astronomy whilst a teenager living in South Wales. During those days, the skies were really dark after midnightwhen the local authorities switched off the street lighting, and I spent many happy hours exploring the sky with a Charles Frank 4-inchNewtonian telescope. However, my interest in practical astronomy faded once I started university.

Moving forward to 2010 with retirement approaching, I once againtook up practical observing using an 8-inch Newtonian. However,I was then living in Stevenage, and light pollution was a realhindrance to visual astronomy. So I began to use photography toexplore the night sky. Mostly self-taught, I captured my firstpresentable image of a Messier object in 2011 when I photographedM 51 using a Skywatcher ED 80 refractor and a Canon 450D DSLRcamera. The arrow in the photograph shows the supernovaSN2011dh, which was first detected just three days before I tookthis photo. I was delighted with this success, and I was hooked.

Since then, I’ve been exploring deep-sky objects by imaging them,including many from the Messier catalogue. During this last Spring,I found myself wondering how many Messier objects have Iphotographed and how many were left to observe. To answer thequestion, I trawled through my observations data and noted the dateI photographed each Messier object in a table. (Note: From the

beginning, I have stored all of the calibrated data on all objects I’vephotographed. Each set of data is stored in its own directory that records the date and the object photographed. For example, the directory20190527_M102 holds all the data for imaging M102 and the first night of imaging was 27 May 2019. This approach enables me to goback through the years and recover data for any object.)

The outcome of my investigations was to discover that I havephotographed 83 of the 110 Messier objects. Some images aremonochrome because I simply wanted to see how the object lookedand how it framed in the field of view. Here, for example, is M 61,a small but beautiful face-on spiral galaxy in the Virgo cluster,photographed this Spring.

I will undoubtedly return to some of these and photograph them incolour next year.

Eleven Messier objects are just too low to observe from my garden– that is below 10 deg altitude when due south. That leaves 16 toobserve, of which five are below 16 deg and must rate as difficultto image at such low elevations. Of the remaining 11, one is anasterism (M 73), and one is a double star (M 40).

That leaves nine objects left to observe, and they are all Springobjects, mostly small galaxies.

M 61

Here on the left is another image from this last Spring that I havenot yet shared with you. This is M 80, a globular cluster whichrises to just 15 deg elevation during June.

This image has very sparse data, only four two-minute subs ofRGB data and was imaged on 13 May. The guiding was verydifficult due to the Jetstream – see the slightly odd shape of thebright blue-white star to the upper right.So my Messier marathon of imaging the objects from mylocation is nearly complete, and I need a new project.

David Davies

M 51

6 Members ContributionsA Simplified Exercise for a Science Project

Story by John Whitehead

On the occasion of the summer solstice, 21st June being also the longest day, I wondered “what is the angle of the Sun’s raysfrom the zenith?” So I decided to measure it, using whatever equipment I had to hand.

1st trial I first thought that the angle of the Sun’s rays could be measured just by using two spirit levels, touching a pieceof metal rod approx 1mtr long. The vertical level was 600mm. An example reading was 390 = 0.65 hence Tan -1 0.65 = 33.02°

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(June Solstice)23‐43⁰ Correct to

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1�� Trial21�� June 2019(June Solstice)Using Tangent

MethodReading 0.6⁰ Low

3�� Trial 28�� June 2019Melbourn Cambs

52:08⁰ Lat 0:016⁰ E LongMost accurate reading usingsmall flat channel + Digital

Angle Meter

2ⁿ� Trial23�� June 2019Using Copper +Digital Meter

To measure angleReading 0.3⁰ high

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© John Whitehead 22ⁿ� June 2019Calculation of the Sun’s Rays to also compute Earth’s tilt axial data.Digitised by Richard White for Capella

1:4 2:302:1511:15 11:30 12:15 12:15 12:30 12:45 1:15 1:30Summer Time12 noon11 am 1 pm 2 pm

Sun’s

Ray

s

33.02°

Ground

Support

Having found this angle, I wondered what is the angle of tilt of the earth in the relation to theplane of the Solar Sytem? The latitude position where I live in Melbourn Cambridgeshire is52.08° Hence the reading was 52.08° - 33.02° therefore = 19.06° at 11:05am. So I continuedtaking readings when the clouds stopped obscuring the sun, in order to plot a curve of myresults. Diagram 1 shows how I did the above test. My graph is shown in (Diagram 3) below.

2nd trial. On the following day having given thought to the problem of reading the angle ofthe Sun’s rays more accurately, I decided to use a Digital Angle Meter. I also found that astraight piece of copper 15mm tubing was easier to handle as my own shadow did not causea problem and the light spot was easier to read. The digital Meter was zeroed in after eachreading using a carefully laid level, as shown in sketch sitting on top of the flat plate.

600

Below is the graph Diagram 3 showing all trials points I plotted includingthe one over the page being the 3rd trial I tried on the 28th June.

Diagram 1

Diagram 3

Example reading390

600

Diagram 2

Ground

Support

White Card 15mm Tu

be

Spirit LevelFlat Plate

Zeroed Reading

New re

ading

I used a piece of precision steel, but a piece of glass would be just as good. Again the readings weretaken at convenient intervals of time (15mins) It was necessary to subtract the result from 90°each time and then subtract the result from 52.08° The result was then plotted as before asoutlined above for my latitude position. On the right (Diagram 2) shows what I did.

Graph of Obliquity

1Mtr Meta

l Rod

Degr

ees

Time

The best reading at 13:10 28�� June 90° - 61.30° = 28.70°Hence latitude 52.08° - 28.70° = 23.38° (difference only 0.05°)

7 Members ContributionsHow to measure the angle and to calculate the Axial tilt of the Earth in relation to the Sun

Continued from previous page

The 3rd Trial On the 28th June, this was the first opportunity of a cloudless sky since the last test, I used a piece of aluminium openflat channel in a bid to increase the accuracy of my readings. I found that when the two dome head screws in the metal channel were carefullyaligned as shown in (Diagram 4a) below, the shadow of the Sun’s rays projected a small shadow on to a small piece of white stiff card Ihad fixed to the foot which improved the accuracy of my readings. I got Richard, Capella’s Editor to photograph what I was doing. Hewas surprised at how clear the projected shadow displayed on the white card.

Getting the Digital Angle reading.

Showing the shadow cast by theSun’s Rays on the white card

along Aluminium Channel

John Whitehead on the Summer Solsticedemonstrating how to measure the angle of the Suns’sRays from which you can calculate the Axial Tilt of theEarth by deducting from the latitude where you are.

You should see therays of the sun as asimple shadow on

the White card.

Tripod

Supporting Bar

Digital AngleMeter

White card

Diagram 4b

Diagram of an Aluminium channel with twodome screws centred to align the sun raysas a clear mark on the white card fixedat the foot of the aluminium channel

AluminiumWindowChannel

Rays fromthe Sun

Piece of white cardsecured to the end of the

Aluminium channelDiagram 4a

The tilt of Earth’s axis to the Sun

The peak of the plotted curve would move during the year. The siderealtime is measured by the rotation of the Earth, with respect to the stars (ratherthan relative to the Sun). Local sidereal time is the right ascension (RA, anequatorial coordinate) of a star on the observers meridian. One sidereal daycorresponds to the time taken for the Earth to rotate once with respect tothe stars. The total angular movement of the Sun’s Rays between Winterand Summer Sol;stice is 23.43 x 2. The peak of the plotted curve on thegraph would be at a different position of time according to your actuallongitude position on the Earth.

Points of interestThe tilt of the Earth gives us theseasons of the year.The Earth’s rotates at a speed of23hrs 56mins and 4 seconds perrevolution giving us sidereal time.

CAA 60 Star Party and Photography Competition.

Friday 11th October 8pm

8 Members Contributions

The CAA was founded in 1959 and has had its ups and downs, but is now a thriving society – we can lookforward to the next 60 years. Members are invited to bring their own telescopes and set them up on theNorthumberland lawn, where Saturn is making a welcome return to the evening sky in autumn. Saturn, althoughstill low, will be joined by Jupiter and the Moon. As usual we’ll have our projection system working, showingwhat celestial objects can be seen on three large screens.

The Photography CompetitionThis competition is open to any paid-up member who can bring along up to two photographs with anastronomical object or astronomy related topic, from deep sky, planetary or lunar images to sunsets, statues,observatories, buildings, etc. Prizes: Crystal ball Solar System trophy for CAA winner, and a telescope for theCYA winner. Members attending the star party will judge the entries taking into account whether you’re anexpert, intermediate or beginner. If bring photos, please arrive early (from 7.15pm) so that the photos get onthe display boards before members start voting at 8.00pm

Star Party Tickets £2.50 for members and £3.50 for non-members or £4.00 at the door on the night.

Pay electronically on our website www.caa-cya.orgOr you can send the money electronically to our account at Barclay’s Bank.Electronic transfer to Barclay’s details:Account name: CAMBRIDGEASTRONOMICALASSAccount number: 10679844 Sort code: 20 17 22Reference: ‘Party’ followed by your name. e.g. Party Joe Bloggs (maximum 18 characters)Important. Once the money has been transferred, please send a covering email to Brian atbtlister@btinternet.com

Or send Brian a cheque made payable to the Cambridge Astronomical Association to;Brian Lister 80 Ramsden Square Cambridge. CB4 2BL

11�� October

Monday 2nd September 11+ group meeting “Don't forget the Inverse Square Law”

Friday 13th September All members and guests CAA 60 Star Party

Friday 27th September Speaker Meeting Cold Dark Matter Dr. Julian Onions

Monday 28th September 7-11yr group meeting Local Group of Galaxies

Monday 7th October 11+ group meeting Galileo

Friday 18th October Speaker Meeting Hawking and the Edge of Physics Paul Fellows

Saturday 26th October 7-11yr group meeting Mini Rockets

Tuesday 29th October CAA/CYA members A walking tour with special exhibits by Joshua Nall

Friday 15th November Speaker Meeting Tracing Black Holes with LOFAR Dr. Judith Croston

Friday 20th December Speaker Meeting The Star of Bethlehem Prof. David Hughes

Capella Editor’s notes.

A special thank you to all the new contributors for all theinteresting articles and pictures you sent for this edition.

But don’t stop there. Anything interesting Astronomy relatedcan be submitted as long as it is entirely your own work.

Please remember to credit the owner of any picture or articleif you have incorporated it into your story. It can even be aninteresting book or video that you want to recommend toothers or as I have done in this edition, a review of a lecture..

I would ask that any information you wish to include inCapella must be in a standard text or word formatdocument. Any embedded pictures you have used in yourstory should be also sent as separate JPG's. You can contactme by email on any content or publication issue atjazzyrjw@gmail.com or phone 07943 945222

Loan Telescopes.Our four existing loan telescopes are easy to use and easyto transport, and usually with no long waiting periods sowhy not give it a try.

We have new loan telescopes we have now added to theexisting loan stock. There will always be one that isavailable to try.Visit our website (www.caa-cya.org) and click to book anInstrument.Alternatively please ring Mickey Pallett on 01480 493045

Display table

At our speaker meetings, we're put out one or twotables for members to display their photographs, bringalong laptops to present their work or even show objectsof interest. Please contact Paul or Brian to make sureit is not already booked in advance.

CAA/CYA NewsDiary Dates See the CAA-CYA website for costs and more details.

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Meetings for the 11+ Group will be held in the Hoyle Building at the Institute of Astronomy, Madingley Road from7.15pm to 8.45pm. Free to CYA members; for non-members there is a £1.00 fee.

“Don't forget the Inverse Square Law”Monday 2nd September 2019

Start time : 19:15Speaker : CAA

11 + Group Meetings

Website: www.caa-cya.org

Chairman : Paul FellowsVice Chairman : Brian ListerTreasurer & Membership Secretary : Mickey PallettSecretary : John HodsonEvents Secretary : Jonathan Clough

Capella Editor and DTP Setter : Richard White jazzyrjw@gmail.comMembers should send stories for inclusion where possible by email to Richard orsend them to Brian Lister Tel: 01223 420954 (evenings) or email btlister@btinternet.comPlease make sure that article text contributions are sent as standard Wordfiles and images as .jpg’s wherever possible.

President : Jim HysomVice President : Carolin CrawfordCommittee : Dave Allen, Kevin Black, Paul Drake, Barry Warman, RichardWhite, Brenda Field, Jonathan CloughCambridge Young Astronomers : (both groups): Brian Lister Tel: (evenings)01223 420954 or em ail btlister@btinternet.comTelescopes for hire to members : Mickey Pallett Tel: 01480 493045 or bookon line.Loan Telescope maintenance : Dave Allen, email day.vid@hotmail.co.ukLibrary : Kevin Black Tel: 01223 473121Webmaster : Paul Fellows: email paul.fellows@ntlworld.com

In 1936 Edwin Hubble used the term “The Local Group” identifying 11 or possibly 12 membergalaxies. Of course the number has grown to nearly 60 now, with the last one being discovered inJanuary this year, but not all by big ground-based or space telescope. Donatiello 1 was discoveredby an amateur last year using just a 125mm refractor he had made up from bits of other telescopes.

CYA Meeting7-11 Year Group“The Local Group of Galaxies”Saturday 28th September 2019

Start time : 10:00Speaker : CAA

“Mini Rockets”Saturday 26th October 2019

Start time: 10:00Speaker : CAA

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Gravity, light and other parts of the electromagnetic spectrum adhere to this equation. We’llbe looking at the importance of this law and what happens when somebody forgets about.

“Galileo”Monday 7th October 2019

Start time : 19:15Speaker : CAA

Galileo began by studying medicine, later he noticed a swinging chandelier that took the same amount of time to swing backand forth, no matter how far it was swinging. This made him change to the study of mathematics and natural philosophy. Hebecame an astronomer, physicist and engineer and has been called the father of observation astronomy.

Ok forget the 10 ton Saturn V rocket motor each with a nozzle the size of a garage and each burning nearly 3 tons of fuelmixture every second! We will be looking at the small stuff, with nozzles sometimes only big as a tin of beans or even smaller!But these tiddly rocket motors still had important jobs to do.