Archive for the ‘Astronomy blog’ Category

WoodDomeConstruction1952The new East Dome is the fourth third dome to be built in the grounds of Sydney Observatory. The third was completed by Harley Wood in 1952. It had brick walls surmounted by a copper dome. The copper dome is now part of the East Dome.



Wood’s dome under construction in 1952. It sat on the same site as the new East Dome. ©MAAS.




SydObsFrontGarden1890sThe new East Dome is the fourth third dome to be built in the grounds of Sydney Observatory. The second was built by Henry Russell in 1880. His star camera was installed here in 1890.


Sydney Observatory’s second ‘third dome’ was constructed from corrugated iron and had a conical roof. ©MAAS.





NASA.2004BL86.radarOvernight on Australia Day 2015 the asteroid 2004 BL86 passed Earth about three times further away than the Moon. NASA imaged it from their Goldstone station (and Arecibo) using radar. The Goldstone data revealed it has its own moon. It also revealed its diameter to be only 325 metres. This is much smaller than the previous estimate of 500-1000 metres which was based on its brightness.


Asteroid 2004 BL86 has its own moon. NASA/JPL.




SydObsFirstThirdDomeThe new East Dome is the fourth third dome to be built in the grounds of Sydney Observatory. The first was built by Henry Russell in the 1870s. It had a shallow conical roof.


Sydney Observatory’s first ‘third dome’ was located beside the white shade pyramid in the front garden. ©MAAS.





This is the eighth post in a series which documents the development and construction of a new domed building for Sydney Observatory which is especially designed for use by people with disabilities and their carers. Officially called the ‘East Dome’ this building was opened today, 27 January 2015, by the Hon. John Ajaka, Minister for Disability and Ageing.  Despite drenching rain the opening event was well attended by distinguished guests.


Guests at the opening event. MAASDirector, Rose Hiscock in foreground.  Photo T.Stevenson

This project was made possible due to financial support from the NSW Department of Ageing Disability and Home Care , the Museum of Applied Arts and Sciences (MAAS) capital works program and  NSW Public Works contributed funding towards the restoration of the heritage dome and the project was managed by Adam Adair of Pure Projects and builders were Zadro Constructions. The building was designed by NSW Government Architects Angus Donald, Vivian Sioutas and Terry King.  The dome house a new accessible DFM telescope with the revolutionary Articulated Relay Eyepiece. It will also display the 1890 Melbourne Astrographic telescope designed and built by Howard Grubb. The dome was originally built by Morts Dock engineering under instruction from NSW Government Architect Harley Wood and was operational from 1952.


The project nears completion. Photo T.Stevenson

In post 1 and post 2 of this series I provided information about why Sydney Observatory is building a new dome, where the dome came from and how the building program is progressing.


4 November 2014, Toner Stevenson with the restored heritage dome prior to installation. Photo C. Rowe.

In post 3 I explained Andrew James’s role advising on accessibility and his deep engagement with the research outcomes from the Astrographic Catalogue and the instruments which were used for that project. In post 4 I confirmed the name ‘East Dome’  and that the concrete pour had been successful and bricks and block-work walls were progressing. In post 5 I described the excitement with the arrival of the historic Astrographic telescope mount. In post I described the exciting day, November 6, when the historic dome arrived and was fitted on top of the new building. A ‘dome topping’ ceremony was held with Deputy Premier Troy Grant and Minister John Ajaka. In post 7 the new telescope from DFM Engineering in Boulder Colorado arrived, was installed and commissioned.


Hon. John Ajaka being interviewed by ABCNews24. Photo T. Stevenson

In the first weeks of the new year there were still many aspects of the new building, and its equipment to sort out. Rotating the dome with the telescope required specialist programming skills because it was old technology (the dome and its motor) meets the new technology of the telescope. Jeff Smith of NSW Public Works and Zadro Construction worked with DFM Engineering to solve this problem. Another exciting event was the delivery of the telescope tubes and the completion of assembly by the MAAS Conservators Carey Ward and Tim Morris and a small band of dedicated restoration volunteers. This took two full days and , with the telescope tubes so tightly fitting the space, there were a few close calls near the glass and ceiling. With the programmable lighting it looks spectacular at night. But even more so once the exhibition graphics were installed.


Carey Ward, MAAS Conservator, installs the Melbourne Astrograph.


Adjusting the plate holder in the astrograph. Photo T. Stevenson

The amazing star field images featured in the exhibition are courtesy of David Malin Awards Winner, Phil Hart. The section of the Milky Way located behind the Astrographic Telescope illustrates the section of sky which Sydney Observatory photographed for the Astrographic Catalogue. A spectacular image of the Great Orion Nebula is at the entry point. This image was chosen because it is the subject of one of the earliest photographs taken by Henry Chamberlain Russell in preparation for the Astrographic Catalogue. This intriguing and much researched and imaged object is also one of the most fascinating to view in a telescope. The exhibition also includes a measuring machine manufactured by Troughton and Sims in Britain and called ‘Sydney A’. There is also film footage of the dome being used by Harley Wood in the 1960s.

The opening event, held 27 January , was simple but meaningful with speeches by MAAS Director, Rose Hiscock, President of the Board of Trustees, Professor John Shine, and the Hon, John Ajaka. I made concluding remarks about the importance of the heritage of astronomy in Australia and how this is a shared concern amongst Museums, Universities, research organisations and the community.


At the opening amateur astronomer Andrew James with Professor John Shine. Photo T.Stevenson

The guests included many people who had worked on the project and those who had been encouraging and supportive, including MAAS Trustees Jim Longley and Bob Cameron;  globally renowned astronomers Dr David Malin and Professor Fred Watson; University of Sydney Museum Studies Pro Dean Jennifer Barrett and astronomers Professors Anne Green and Elaine Sadler; ESA engineer Warrick Holmes; UNSW Professor Michael Burton and  UWS Assoc. Professor Miroslav Filipovic. There were people who had been involved at the very beginning and the architects, designers, collection and exhibitions staff who had seen it through to completion. Many amateur astronomers and astronomy enthusiasts joined us and all attendees were offered a tour of the new facility by the Sydney Observatory project team curator Andrew Jacob and education program manager Geoff Wyatt.

One of the important outcomes from this project is that research I have produced for my doctoral Museum Studies thesis about the Astrographic Catalogue, and the women who worked on it in Australia, provided the foundation to establish the  sociological significance of the project to Sydney Observatory and a much deeper understanding of the women’s work and its extent than had previously existed. It was therefore fitting that star measurer and computer Winsome Bellamy , and Ros Madden, the daughter of Harley Wood, were able to attend this event as well as the amateur astronomers who were the last people to use the Astrographic Catalogue to photograph Halley’s comet in February 1986, just before it was transferred to Macquarie University.

I hope you come to see the East Dome and book into a tour to use the telescope. You can wander through the exhibition for free during the day 10am to 5pm, and the telescope will be available as part of the night and day tours from March 2015. The next and final blog post will show the completed exhibition.


Testing the lighting at night. Photo T.Stevenson


T. Stevenson (2014). Making Visible the First Women in Astronomy in Australia: The Measurers and Computers Employed for the Astrographic Catalogue . Publications of the Astronomical Society of Australia, 31, e018 doi:10.1017/pasa.2014.12.

T. Stevenson (2013). Making Visible the first Women in Astronomy in Australia, slide presentation about women in astronomy:

T. Stevenson (2013) presentation to the Women in Astronomy workshop, 2013:

EastDomeBuildFinalStagesSydney Observatory’s new East Dome officially opens today, 27 January, 2015. It is one of three domes on the site. The south dome was built in 1858 (enlarged in 1874) and the north dome was added in 1877.


Last minute final touches being applied to the new East Dome at Sydney Observatory. ©MAAS.




Daily cosmobite: The Australia Day asteroid 2004 BL86

Published by Andrew Jacob on January 26, 2015 No Comments

Arecibo_ObservatoryTonight asteroid 2004 BL86 will pass Earth, but three times further away than the Moon. The Arecibo radio telescope will measure its size and shape using radar. Asteroids pass Earth every day but this will be the closest by one this big, i.e. over 500m, until 2027. You will need a computerised telescope and a dark sky to see it.

The Arecibo radio telescope in Puerto Rico will measure the size and shape of asteroid 2004 BL86. 




As the First Fleet sailed into Sydney Harbour on Saturday 26 January 1788, there was no light pollution. The weather was clear and they would have had a clear view of the night sky that today, we can only imagine!  The Milky Way, stretched right across the sky from South to North, the two Magellenic Clouds, Sirius and the stars of the constellations Orion , Taurus and Crux (the Southern Cross) and the planets Jupiter and Mars were seen amidst a celestial sphere of thousands of stars which we can only see from Sydney through telescopes now. There was no daylight saving time. You too can see the sky as it was in 1788 recreated in Sydney Observatory’s planetarium on Australia Day 2015 in our program which runs from 10am to 5pm. Details here.
With no light pollution this is what our sky above Sydney looked like in 1788.


The Sydney Sky 26 Jan, 10pm,1788 . Image using @StarWalk

Daily cosmobite: The Sydney Star Camera, 1891

Published by Andrew Jacob on January 23, 2015 No Comments

RussellsStarCamera1891Henry Russell designed his own photographic telescope, or “astrograph”, to photograph large parts of the southern sky for the Astographic Catalogue project. He called it a “star camera”. It was used from 1890 until the 1940s.


Russell’s ‘star camera’ telescope under a conical ‘dome’ in the front garden of Sydney Observatory in about 1891. ©MAAS.




Daily cosmobite: The Astrographic Catalogue

Published by Andrew Jacob on January 22, 2015 3 Comments

Vol1.AC.SydneySectionThe aim of the Astrographic Catalogue project was to photograph the entire sky and measure the positions of all the recorded stars. It began in 1887. Sydney Observatory’s section was published in 52 volumes and contained 740,000 star positions.



The cover of Volume 1 of the Sydney section of the Astrographic Catalugue. ©MAAS.






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