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The Australian Museum Society Fred Watson, AAO 17 May 2005

When telescopes go. BAD. Well, this is rubbish…. The Australian Museum Society Fred Watson, AAO 17 May 2005. Prologue… On 2nd October 2008, we will celebrate the 400th birthday of this document. It records the first appearance of a telescope.

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The Australian Museum Society Fred Watson, AAO 17 May 2005

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  1. When telescopes go BAD Well, this is rubbish… The Australian Museum Society Fred Watson, AAO 17 May 2005

  2. Prologue… On 2nd October 2008, we will celebrate the 400th birthday of this document. It records the first appearance of a telescope.

  3. But by 2008, we will also be on the brink of a new generation of unbelievably large telescopes. What lessons can we learn from the 400-year history of telescope making…?

  4. When telescopes go BAD The secret obsessions of astronomers

  5. Characteristics of astronomy today • Huge range of instrumentation • Infinite computing power • Access to every part of the electromagnetic spectrum:-rays,X-rays,UV,visible (optical),IR,mm-wave,radio

  6. The Universe through different eyes...

  7. What’s so good about opticalastronomy? • Visible light is emitted by ‘ordinary matter’ in the Universe—i.e. stars • The visible spectrum is rich in the ‘bar-code’ of atomic and molecular features • Optical observations bridge long and short wavebands • You can do it with your feet on the ground

  8. The Schematic Ground-Based Optical Telescope • Something large to collect and focus the radiation • A complicated bit in the middle for analysis • An optical detector • A ground-based mounting Now essentially perfect

  9. To gather more light from faint sources, telescopes need to become ever bigger

  10. Bigger telescope mirrors can also reveal finer detail in the sky… << So astronomers want to make them bigger still >>

  11. When telescopes go BAD Cautionary tales:the bad telescope casebook

  12. Bad Telescope Casebook... Andrew Barclay and the ‘Unrevealed Wonders of theHeavens’

  13. Andrew Barclay (1814-1900) Locomotive builder from Kilmarnock Became hooked on building telescopes on the side. While they were beautifully engineered, his telescopes were small and old-fashioned by the standards of the day. And his mirrors were absolut-ely hopeless. But Barclay refused to believe they were…

  14. Andrew Barclay’s Mars… Barclay also described a ‘blue, spherical-looking mountain’ in Mars’ southern hemisphere (1893)

  15. His version of Jupiter… Barclay’s ‘egg-shaped protruberances’ were later reported to have brown smoke issuing from them.

  16. And Saturn…

  17. The response to Barclay’s work… Barclay’s results appeared in the English Mechanic and were received with utter derision: ‘I can only say that if I had a telescope that exhibited the great planet as depicted in Mr B’s Fig.1, I would dispose of the optical part for what it would fetch, and convert the tube into a chimney cowl straightway.’ (And that’s one of the kind ones.) Barclay protested that he had spent £10,000 learning how to make telescope mirrors. How could there be anything wrong with them? He was clearly not only obstinate, but also stupid.

  18. Moral number one: Make your mirrors good ones (and listen to people who tell you they aren’t…) When telescopes go BAD

  19. Bad Telescope Casebook... Johannes Hevelius (1611-87)and his telescopes

  20. The wealthy brewer of Danzig Hevelius spared no expense in equipping his state-of-the-art optical workshop…

  21. …and working with his young (second) wife Elisabetha, who was: ‘the faithful Aide of my nocturnal Observations’.

  22. The wealthy brewer of Danzig His early instruments were stylish (and stylishly used). This one dates from 1647. But then he caught galloping megalomania.

  23. First, he built a 60-foot (18-m). Then a 150-foot (46-m)…

  24. But in the end, his quivering telescopes were destroyed in the Great Fire of 1679: ‘The cruel flames have consumed all the Machines and Instruments’.

  25. Moral number one: Make your mirrors good ones (and listen to people who tell you they aren’t…) When telescopes go BAD Moral number two: Understand the mechanical limitations of your telescope…

  26. Bad Telescope Casebook... Sir James South(1785–1866) and the telescope that sparked a feud

  27. South was a gifted amateur astronomer of independent means (a surgeon by profession). He was knighted for his services to astronomy (the measurement of double stars), but was outspoken in his criticism of the establishment. He was president of the RAS, 1829–31.

  28. Secretary of the RAS at the same time was Rev. Richard Sheepshanks, the forthright son of a Yorkshire mill-owner. Just watch it, Sheepshanks. With degrees in mathematics, theology and law, he was scornful of those less talented than himself. Especially Sir James… Woof! Get a brain, South.

  29. Late in 1829, South bought an exquisite 12-in telescope lens. He placed it in the hands of his then-friend, Edward Troughton, asking him to construct Britain’s most powerful telescope. They disagreed on the design…

  30. By 1832, Troughton’s telescope had failed to satisfy South. He accused Troughton and his partner, William Simms, of building “a useless pile”. Troughton took legal action to recover his firm’s costs. Guess who he hired as his lawyer? Troughton & Simms won in 1838, enraging South. So, in 1839…

  31. The scene at Sir James South’s, 8th July 1839… “…the useless 20ft equatorial invented by Troughton and Simms, and cobbled by their assistants the Rev. R. Sheepshanks and Mr. G. B. Airy…”

  32. And, in 1842… South attempted to complete the humiliation of Troughton & Simms and their allies by addressing the humblest categories of tradesmen in the district… South’s vitriol continued even after Sheepshanks’ death in 1853… The great lens was never properly used by South.

  33. Moral number one: Make your mirrors good ones (and listen to people who tell you they aren’t…) Moral number two: Understand the mechanical limitations of your telescope… When telescopes go BAD Moral number three: Agree on exactly what you want - before you start…

  34. Bad Telescope Casebook... And one final moral: Put your telescope in the right place…

  35. When telescopes go BAD Against the odds: how icons are created

  36. The 100-inch Hooker telescope (1917) Why did it become an icon…?

  37. The Eagle Nebula—stellar birthplace

  38. The Eagle Nebula—stellar birthplace

  39. But – the Hubble cost $US 2 billion to build, launch and fix. That would buy 20 of today’s ground-based 8-metre telescopes…

  40. A 3.9-metre mirror can see detail of 0.03 arcsec…

  41. 1 arcsecond Stars should look like this… This is very depressing indeed 

  42. But unusual things happen in Australia…

  43. The answer to life, the Universe and everything... Spectrograph Slit Detector Multi-object spectroscopy with fibre optics

  44. Basic building-blocks of the Universe If this was our Galaxy, we’d be here Galaxies… • Around 100,000,000,000 stars • Lots of gas and dust (in spirals) • Around 100,000 light years across (or 1,000,000,000,000,000,000 km)

  45. When telescopes go BAD Applying the lessons…

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