Archive for the ‘Astronomy blog’ Category

This is the fourth blog in a series which documents building a new dome for Sydney Observatory which is especially designed for people with disabilities and their carers. This project is important to our visitors. Every day and night Sydney Observatory staff  explain to people visiting who cannot make it up the 39 steps to the North and South domes that a new future awaits thanks to funding from the NSW Department of Ageing Disability and Home Care. Over the past week this future was locked with building works on schedule for completion by Christmas. Installation of the new accessible DFM telescope with the revolutionary Articulated Relay Eyepiece is about to be locked in and the exhibition will be installed early January leading up to a grand opening late January 2015.

Astrographic dome

MAAS Facilities team head, Danny Grant, in the white safety helmet, inspects the building work. Photo T. Stevenson

In blog 1 and blog 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. In blog 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 will feature in the display inside the new building.

Over the past week we have confirmed the name of the new dome as the ‘East Dome’.  This does not seem very imaginative but it keeps within an already established hierarchy which goes back in time with the South Dome, built in 1858, and then the North Dome built 1877-78.

In the photograph above MAAS facilities manager, Danny Grant, is consulting John Winter from Zadro Constructions, about the finish on the concrete floor and placement of power. This image was taken mid week and by the end of the week the main structural walls had really taken shape, with the bricklayers expertly  forming the circular base of  the East Dome. Great weather has helped the project move quickly now. In the photograph below you can see the circular wall of the dome and the vertical concrete block wall which separates the foyer and display space from the dome. The challenge now is to crane the original copper dome on top of the building. Our project Manager Adam Adair from Pure Projects is working closely with Carey Ward. Carey was an instrument maker for Sydney Observatory when the MAAS became custodians of the site. He is now Project Manager, Conservation and its great he is involved in the project and seeing the return of an important part of the collection in a way which enhances the programs we can offer visitors.

Astrographic Dome

The concrete block wall on the left is almost at its finished height and the circular brickwork of the dome walls takes shape. Photo T. Stevenson.


Its now clear that NSW Government Architects have considered the placement of the building on the site very carefully. The blockwork and brickwork will be rendered smooth to contrast with the texture of the stonework of the original Sydney Observatory building.

Astrograph Dome

The walls reach their final height, 10 October 2014.


Sarah reports on the total lunar eclipse for October 8, 2014

Published by Andrew Jacob on October 10, 2014 No Comments


The full Moon reddened during the total lunar eclipse of October 8 2014. Image copyright Geoff Wyatt.

The full Moon reddened during the total lunar eclipse of October 8 2014. Image copyright Geoff Wyatt.

Sarah is one of Sydney Observatory’s expert astronomy Guides. She took time out from her PhD studies at the University of Sydney to help bring the total lunar eclipse of October 8, 2014 to Sydney. Here is her report:

On Wednesday night Sydneysiders were treated to a spectacular sight – the “blood”moon of a total lunar eclipse. About 200 people gathered in the grounds of the Observatory hoping to catch a glimpse.

Although the Moon hid behind clouds for much of the night, their patience was eventually rewarded – a little after 10pm the clouds cleared briefly, revealing a stunning red moon.

How do Lunar Eclipses occur?

Lunar eclipses occur, on average, around twice per year, and from any particular location they are seen far more often than solar eclipses. A lunar eclipse happens when the Sun, the Earth and the Moon line up exactly so that the Moon is covered by the Earth’s shadow.

There are three kinds of lunar eclipse – penumbral, partial and total. Penumbral eclipses occur when the Moon falls in Earth’s penumbra (the fainter part of our shadow). A partial eclipse occurs when a portion of the Moon is covered by the Earth’s umbra (the darkest part of our shadow), and a total eclipse occurs when the entire Moon is inside the Earth’s umbra.

Total eclipses, like the one we saw on Wednesday, account for less than half of all lunar eclipses. However, the last eclipse on 15 April 2014 began a run of what will be four total eclipses in a row.

Why does the Moon appear red?

Even when it is completely obscured by the Earth’s shadow, some of the light from the Sun will be bent around the Earth and reach the Moon. As this light passes though our atmosphere, the blue light is scattered away and what’s left is the red light (this is the same reason that sunsets are red). In other words, it’s like the Moon is being lit up by the red light of all of the sunrises and sunsets around the globe.

Viewing a lunar eclipse

Unlike solar eclipses, a lunar eclipse can be seen from anywhere that is experiencing nighttime when the eclipse occurs. Lunar eclipses are also safe to view with no special eye protection, and fun to photograph.

For those who missed Wednesday’s event, you won’t have to wait too long – the next total lunar eclipse is due to occur on 4 April 2015.

TLE08OCT2014. totalityThe Moon’s orbit around the Earth is tilted by about 5-degrees to the orbit the Earth takes around the Sun. So the Moon usually passes above or below Earth’s shadow when it is full. Only about twice each year do the orbits align causing the Moon to pass through Earth’s shadow – this is a lunar eclipse.



The totally eclipsed Moon on October 8, 2014. Image cropped from live stream, ©MAAS.

Daily cosmobite: Full Moon and synchronous coral spawning

Published by Andrew Jacob on October 9, 2014 No Comments

Stony_coral_spawning_2 Many corals on the Great Barrier Reef will begin their synchronous spawning between one to six days after the first full Moon in October – that would be about now!



A male star coralMontastraea cavernosa, releases sperm into the water. Image from NOAA via Wiki.

Daily cosmobite: Total lunar eclipse tonight, Oct 8 2014.

Published by Andrew Jacob on October 8, 2014 No Comments

Eclipsed Moon by Geoff Wyatt A total lunar eclipse occurs tonight, October 8, 2014. It is best seen from 8:15pm AEDT to 11:35pm AEDT. During totality the Moon appears red, but the shade of red is impossible to predict.


 The reddened Moon during a total lunar eclipse. Photo © Geoff Wyatt.


Daily cosmobite: Does the full Moon affect our behaviour?

Published by Andrew Jacob on October 7, 2014 No Comments

Moon showing the area of Plato by James Short and H. C. Russell 1891 The full Moon affects Earth only through its gravity and light. This might influence the time we go fishing or inspire us to write a pop song. However, there is no conclusive evidence that it affects crime rates, emergency ward admissions or lycanthropy.



 The Moon near the crater Plato. Photographed by James Short and Henry Russell at Sydney Observatory in 1891.




FrodshamClockFaceMAAS Daylight Saving Time begins in NSW, Victoria, SA, Tasmania and the ACT tonight. Dont forget to put your clocks forward by one hour before going to bed. Official time for daylight saving is 2am Sunday 5 October.




 The face of the Frodsham clock, which kept time for NSW for many years, on display at Sydney Observatory. Photo © MAAS.




Daily cosmobite: Earth and asteroid 4766 Malin

Published by Andrew Jacob on October 3, 2014 No Comments

Asteroid 4766 Malin, named after renowned Australian astrophotographer David Malin, has its closest approach to Earth today. However it is still 1.5 times further from us than is the Sun. The real David appears below at the opening of the 2014 Winning Sky Photos exhibition. The exhibition is on display at Sydney Observatory until 2 November before travelling around Australia. Photo © MAAS.

David Malin at WSP 2014

Dr David Malin at Sydney Observatory

In blog 1 and blog 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. I have already introduced you to some of the people involved in the project and our major supporters of the project, NSW Department of Aging, Disability and Home Care and the Museum of Applied Arts and Sciences.

Astrograph Dome

Architectural drawing by NSW Government Architects.

Over the past week progress has been made in completing the concrete pour so the external ramp and patio are now in place and the blockwork walls are just starting to rise. The other big step forward is the appointment of our publicist and a big effort by Andrew Jacob on the curatorial work, drafting labels and liaising with the designer.   Dr Andrew Jacob took over a large proportion of the astronomy, horology, meteorology and surveying curatorial roles for the Museum after Dr Nick Lomb, a well-known astronomer, retired in 2009. Andrew is curating the interpretation of the new dome and advising , with Education Manager, Geoff Wyatt, on the telescope.

Astrographic telescope.

The ramp and ‘patio’ slab were poured.

Selecting the best telescope was a major piece of work. Geoff prepared comparisons between many available instruments which would give the best viewing in a city environment and did preliminary budgets for six options. Andrew James, amateur astronomer and astronomy history expert, advised on the selection, and its placement in the dome from the viewpoint of a wheelchair-user. The final decision was to purchase a telescope from a company in Colorado called DFM Engineering which has a purpose-built attachment, called an Articulated Relay Eyepiece.   This extended eyepiece enables a person in a wheelchair to use the telescope by moving the eyepiece closer to them, as demonstrated in the image below, rather than trying to get the person in the wheelchair into a viewing position. It is unique to DFM Engineering.

Astrographic Dome

The Articulated Relay Eyepiece attached to the DFM telescope. Image courtesy DFM.

This week Andrew James came in to see the building progress, discuss some ideas he has for exhibition content and talk in more detail about the finishes and finer points of design. He was very pleased to see we had installed two ‘windows’ into the building site – one at a high and one at a low level- so everyone can see progress on the building. This will enable viewing into the building ‘showcase’ so the 1890 Astrographic Telescope. Andrew Jacob discussed the exhibition design by Claudia Brueheim which enables wheelchair users to get close to the objects and read the labels at a convenient height.

Astrographic dome

Andrew James, skilled amateur astronomer, inspects progress on the new dome.

Jewel Box

The Jewel Box Cluster. Image and copyright M.Bessell, CSIRO.

Then we all enjoyed safe solar viewing with the portable H-Alpha telescope of interesting sunspot groups and a large prominence. Whilst Sydney Observatory has provided an outdoor telescope service for many years for persons with disabilities there is nothing like a dome experience. We discussed the interesting research around the Jewel Box open cluster of stars and double stars which Andrew James has been investigating, and how this beautiful and interesting group of stars was photographed using an Astrographic Telescope in the 1890s, and was still the subject of detailed research in the 1980s. Andrew James is looking forward to bringing in a group from the Muscular Dystrophy Association to experience the new telescope so he can share his enthusiasm and knowledge of astronomy in the dome.

Astrographic telescope

(L to R) The ‘A’ team: Andrew Jacob, Andrew James and Andrew Smith discuss telescopes, wheelchairs and solar observations

Harley Wood on site search In 1958 Harley Wood (on the right), NSW Government astronomer, traveled around NSW inspecting sites for telescopes. Here he is in Dubbo planning the next stage of the search. One of the sites he may have inspected became the Siding Spring Observatory. This long weekend the Observatory holds its “StarFest” open day and celebrates 50 years of operation.


Harley Wood (right) planning site searching, July 1958. Photo © MAAS.



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