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Self-guided tour VIEWING THE TRANSIT OF VENUS 2012 ‘Every so often the planet Venus does something remarkable. Its orbit brings it to a point directly between the Sun and the Earth, where it appears to us as a black dot moving across the bright disc of the Sun … it has fascinated astronomers for centuries.’ Nick Lomb, Transit of Venus: 1631 to the present, 2011 To coincide with the 2012 transit of Venus, Sydney Observatory presents images and artefacts reflecting the significance of this event. The display draws on research by two Sydney Observatory astronomers: Henry Chamberlain Russell’s observations of the 1874 transit, and Nick Lomb’s complete guide to the 2012 transit. This exhibition is all around Sydney Observatory. Look for showcases with this model to discover more about this prized celestial event. It won’t happen again until 2117! GROUND FLOOR Entry ‘Predictions and the future’ Richard Proctor’s 1874 diagrams show where the transit of Venus would be visible. His 2012 map clearly shows that the east coast of Australia is one of the best places to view the transit of Venus. Front Desk ‘The reinforcement camps’ Photographs and sketches from various other sites around NSW and Melbourne that also viewed the transit of Venus in 1874. Room 1 ‘The world stage’ Under Henry Chamberlain Russell’s direction Sydney Observatory was able to contribute globally important information on the 1874 transit of Venus. This bought Russell to the attention of the British astronomers and he was recommended as the astronomer to represent the colonies of Australia at the international Astrographic Congress. The first meeting was held in 1877 at Paris Observatory. Some of the things you will see: • Audio visual of Henry Chamberlain Russell — gives insights into the man and astronomer. • Henry Chamberlain Russell photographs, including family photographs from his return journey after attending the 1877 International Astrographic Congress in Paris Room 2 ‘The early tools’ This room looks at the instruments used by early map-makers and navigators with a focus on Matthew Flinders. Clocks and chronometers were very important tools, which used with telescopes and star catalogues, gave them the information needed to navigate their way around the globe. Some of the things you will see: • Earnshaw 520 Chronometer — one of the five chronometers used Above: transit maps 1631 and 1639, 1761 and 1769, 2004 and 2012; the on Flinders’ voyage around Australia. reinforcement camps; Henry • Earnshaw Clock — make sure you also see the Shelton clock Chamberlain Russell. further on. Room 3 ‘Edmond Halley: the man of method’ Our transit of Venus showcase in this room features Edmond Halley and the technology available in the 1760s. Halley formulated a method for observing transits using the concept of parallax, timing and trigonometry. His method started an ‘astronomical race’ to gain measurements from across the globe. Some of the things you will see: • Halley’s Star catalogue — was the first catalogue to be published containing the locations of southern hemisphere stars. • Transit of Venus orrery — this replica of a 1760 orrery gives a three dimensional view of the transit event. It was an important demonstration item. • Brass telescope — this telescope illustrates the type of technology available in the 1760s Also featured in room 3: • Malin Award winning transit of Venus photograph — Geoff Wyatt’s stunning image of the 2004 Transit of Venus Room 4 ‘Venus observed’ This room contrasts how Venus has been observed over centuries. Some of the things you will see: • Galileo telescope (replica) — Galileo was one of the first to describe Venus as viewed through a telescope. • Globe of Venus: the veiled planet — mapped by the Magellan Spacecraft between 1990 and 1994, this globe shows a modern view of the planet Venus. Base of the stairs The instruments used for timing the transit of Venus needed to be very precise. The Royal Society and the Board of Longitude had five astronomical clocks commissioned by John Shelton. Cook took one of these clocks to Tahiti. Some of the things you will see: • Shelton Clock — this clock is identical to the one James Cook took on his voyage. Lent by Martyn Cook Antiques Sydney. TOILETS (outside) 5 EMERGENCY WHEELCHAIR/GROUP EXIT ENTRY GROUND FLOOR 4 3D Space Theatre Above: Edmond Halley; transit of EMERGENCY EXIT Venus orrery; Malin Award winning ENTRY/EXIT transit of Venus photograph; a similar Shelton clock, © The Royal Society 3 Shelton Planetarium RS.8470. Clock 1 (occasional sessions) 2 Right: Sydney Observatory, ground EMERGENCY floor. EXIT FIRST FLOOR South Dome Stairwell — The Sydney and Eden equipment Some of the instruments used for timing and viewing the 1874 transit can be found here. Some of the things you will see: • Breguet Astronomical Clock — timed the 1874 transit of Venus at Eden on the southern coast of NSW • Large Equatorial Telescope photograph — this telescope used to view the 1874 transit of Venus in the South Dome, here at the Sydney Observatory. South Dome Continue up the stairs to see the telescope purchased especially for the 1874 transit by H C Russell. It is still used today during night tours with our astronomers wearing cotton gloves to protect it. Room 6 ‘Australia, Tahiti and the transit of Venus’ This room features the two most important transits of Venus for Sydney — the 1769 transit recorded by Captain James Cook and the 1874 transit captured by Henry Chamberlain Russell. James Cook showcases These showcases illustrate the preparation and anticipation surrounding the 1869 transit of Venus. ‘We went to rest anxious for the events of tomorrow the evening having been very fine gave us however great hope of success.’ Joseph Banks Some of the things you will see: • Transit of Venus observation notes by James Cook — some notes and sketches of the 1769 transit • Captain Cook medallion — Cook was a national hero on his return, this Wedgwood medallion commemorated his success • HMB Endeavour model — a replica of the ship Cook spent 3 years aboard • Voyage of the Endeavour map — this map traces Cook’s South Pacific route to, not only find the great southern continent, but to observe the transit of Venus in Tahiti. North Dome Balcony 10 11 FIRST FLOOR 6 Russell room 9 12 Above: Breguet Astronomical Clock; James Cook; Voyage of the Endeavour South map. Dome 7 8 Right: Sydney Observatory, first floor. Henry Chamberlain Russell showcases The 1874 transit of Venus showcases display equipment used to time and photograph the transit as well as some of the results produced. ‘Never perhaps in the world’s history did morning dawn on so many waiting astronomers as it did on the 9th of December, 1874. They were all anxiously looking for an answer to the old question, to be, or not to be, and certainly none could have expected a finer day than that which dawned on the observers of New South Wales.’ Henry Chamberlain Russell Some of the things you will see: • NSW Observers of the 1874 transit — montage of the NSW transit observers • Hornby Chronometer — used also at Eden to time the transit • Transit of Venus book — published by Russell in 1892, the 1874 transit of Venus details • Photoheliograph — used to observe the transit at Woodford, NSW North Dome ‘The results of the 1874 transit of Venus’ Great attention was given to the transit of 1874. Henry Chamberlain Russell’s records from the 1874 transit of Venus were some of the most detailed at the time. Some of the results are featured in this room. EXPAND YOUR UNIVERSE If you want to become more involved in astronomy and Sydney Observatory you can: • take an adult astronomy course • book a night or day tour • join the Sydney City Skywatchers astronomy club • like us on Facebook • follow #sydneyobs on Twitter. Above: NSW observers of the 1874 transit; photoheliograph; Henry Chamberlain Russell’s records from Sydney Observatory, part of the Powerhouse Museum, is a NSW government cultural institution. the 1874 transit of Venus. © 2012 Trustees of the Powerhouse Museum.
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