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TBS&E Number 72 1 This issue was intended to bring you up to the end of my 2016 adventures, sadly another target missed, with some 2016 bits and pieces left over and several January Still in Century Gothic! to March events written up and waiting. Produced by Garry Dalrymple as So, let us just imagine that I have written something brilliant and incisive in this his contribution to mailing No. editorial space. As ever, it is rather busy in 295, of the Australian and N.Z. my head, no matter how idle mu hands. Amateur Press Association. So far this year there have been record heat, followed by record wet spells, not Postal Address: 1 Eulabah Ave., very conducive to my getting up and out much. I wait for Amber to have another EARLWOOD NSW 2206 fit, she goes a week between them, then Home ph. (best after 7 pm) currently nearly a month. Does the heat, 02 9718-5827 cold or exercise help or hinder them? Several Freecon-ish projects are on the Email; [email protected] launch pad at the moment, as ever, their fatal flaw will be the need to rely on other people. The Great Coffee Bean saga may feature in next month’s issue (I already have enough to hand for TBS&E #73). So let’s start off the issue with … The November 7, 2017, Sydney City Sky-watchers meeting; Speaker; Jesse Van Sande from Sydney Uni. Physics Dept., Topic; Dawn of the Red and the Dead. Who was there? – 24 people, 15 M and 9 F. Club News – The December meeting will be an end of year dinner at The Village SEE THE BACK PAGE Inn. There will be a talk by Fred Watson on (page 40) FOR INDEXES Wednesday November 23, Topic, John Tebbutt F.R.A.S. 1 TBS&E Number 72 2 Member’s Observations – comparison with what we can observe of Garry Dalrymple – Sunspots have been the other Galaxies of the Universe, their star absent or too small to be visible to a 76 mm populations and their state of evolution. diameter telescope. There will be a In about two Billion years our Galaxy and Gravity talk by Ian Bryce at the 2016 Sydney Andromeda (M41) will approach each Freecon. Much has been made of the other, and their outer envelope of stars will ‘Supermoon,’ a Full Moon coinciding with it interact well before an eventual collision being at a point in the cycles of it’s orbit and merger. By about 3.85 Billion years, which is closest to Earth. this will cause star formation due to the Monty Leventhal – Solar activity is down, compression of this dust and gas will ignite numerous sunspot free days recently. a period of star formation. By five to Activity limited to Solar Prominences, seven Billion years the mass of stars will be observed across the disc of the sun, or at so mixed as to form a giant Elliptical the Sun’s edge as hedgerow flares. Active (Football shaped) Galaxy. Thus, the Milky groups observed between the third and the Way is on its way to becoming ‘Red and fifteenth, with groups reducing down to Dead,’ as all the gas and dust of the isolated single spots. During this time, even galactic halo is used up, so that there can the Prominences and Filaments have been be no further new star formation resulting in faint and not very high. the remaining stars being only the smaller, longer lived and age reddened Stars. The Topic; Dawn of the Red and Present day Galaxies can be placed in an the Dead. age / development sequence called The speaker’s recent observing career has Hubble’s Tuning Fork. This graphically involved a Chilean observatory, with four summarises 14 Billion years of Galactic telescopes, 8 metre mirror etc. This array evolution, unconsolidated matter to Spirals costs about $100,000 per night to run. He and barred Spiral forms, do they selected five Galaxies to observe, spending necessarily proceed from Spirals to four to five hours observing. The results from Elliptical. The temptation is to expect these observations were that, from the more structure to emerge with time, spectroscopy of individual stars, that they however this is wrong, with groups of were moving turbulently, rather than in Galaxies being gravitationally bound, the ‘relaxed’ and orderly orbits around their process of merging will produce Elliptical Galaxy’s centre of Mass (A Black hole?). forms, after a very messy process, resulting Observation of Older and more distant asymmetrical / irregular forms, some which Galaxies revealed that they were more retain visible dust lanes from their previous compact than current day Galaxies, i.e. forms. they have already gone through a ‘fire sale’ The Process of Galactic Formation and period of converting dust and gas into short Evolution may be summarised as; lived stars. So, these Zombie Galaxies will Gas Rich to Dusty Active to Quenching to have to fill out the rest of their lives by Compact and Quiet (Zombie stage) to Dry consuming other smaller mass Galaxies. Mergers (For smaller ones) and Finally the Early in the formation of the Universe, son end stage, homogeneous Elliptical form. after Matter became possible, Large First To study Galaxies is like studying forests, in Generation Stars formed out of the that the observer cannot observe the Hydrogen, but because of their size these whole live of a single Galaxy, but you may burnt brightly and quickly, exploding to observe many Galaxies at different stages produce the enriched matter that was to of life. The makeup of Galaxies differ, its form the Second Generation stars, of which constituent stars vary in age, size and our Sun and Planets are formed from. number, all of which may be plotted on a We are able to evaluate the history and Hertzsprung Russell diagram, setting out the future of our own Galaxy, The Milky Way, by likely past and future of these stars. By being able to identify similar stars in 2 TBS&E Number 72 3 different Galaxies comparisons of age and have to look forward to for the next ten distance may be calculated for some billion years of the Universe? Galaxies, but some Galaxies are recorded Not much, as most of it has already only images which are only several pixels happened and we will get to spend the wide. The SLOAN Digital Sky Survey, a single rest of Time with, in effect, a Universe Telescope covering 35% of the sky and populated by Zombie Galaxies! 225,000 stars, which allows greater detail of an average Galaxy to be generated from The November 23, 2016, Sydney this wealth of new details Observatory meeting, Galaxies are more than just the visible stars, Speaker; Dr Fred Watson. Dark Matter, dust and Gas are associated with and make up much of the mass of a Topic; The life of John Tebbutt. Galaxy. Who was there? – About 20 people. The COBE with its image of the cosmic The Topic; The life of John Tebbutt. Microwave background, the first light after I attended the talk, but I decided not to the big bang, with slightly hotter and cooler take any notes, as after trove editing 2,000 areas, with these very small differences or more of his newspaper items, there being what gave rise to Stars, these cooler wasn’t going to be much revealed about areas allowing matter to condense into stars John Tebbutt that I wasn’t already well etc., then seeding Galaxies and greater aware of. This may sound conceited, but Universe spanning bubble structures. it proved to be true on the night. All of these observations are of a moment Also, I wanted to concentrate on what from the past that is frozen in time, distant unexpected points did emerge and what images arriving to us as the Speed of Light. Fred Watson’s approach to Tebbutt was This allows us to look out to distant objects going to be. and to see back into time. Since 1927, the Discovery by Edwin Hubble Fred is of course a professional / academic of a relationship between an object’s Astronomer (and these days a Keynote Distance and the Red shift of its light as Public Science Speaker), and his approach received on Earth. The higher the red shift was the marvel at the achievement of of spectral lines (to the Red) the greater its Professional level observations emerging Velocity and Distance. This effect was from an Amateur. A valid point of view, actually discovered two years earlier in a and necessarily a comparison with the Dutch Monk, but not his results were efforts of Sydney Observatory were made. unpublished. In light of the similar quality of work of W. F. Very distant objects can be very hard to Gale, C. J. Merfield, James Nangle etc., observe, being fainter and offering less and the other 1800s to 1900s B.A.A. N.S.W. resolution. Infrared wavelengths offer (and Victoria Branch) Astronomers, this was better observing prospects and the Hubble a bit naïve, but perfectly understandable, Space Telescope (H.S.T.), being above the not being a part of his tribe’s story. Earth’s atmosphere, is able to observe Faults and complaints – This event was beyond visible light frequencies. The H.S.T. presented as a Tebbutt Tribute event, was aimed at a very empty section of deep marking the centenary of his death in 1916. space for over 500 hours. An image made And I believe this should have been a up of 2,000 stacked exposures revealed much celebrated event.