Archive for the ‘Astronomy blog’ Category

Daily cosmobite: Orionids meteor shower is peaking

Published by Andrew Jacob on October 21, 2014 No Comments

Orionids.TheSky.2014The Orionids meteor shower reaches its peak on October 20 or 21. The meteors are caused by dust from Halley’s comet entering our atmosphere. Look for them after midnight from a dark place.






Orion is in the north-east sky at 2am in mid-October. Look for fast meteors radiating from below Betelgeuse, the orange star of Orion’s shoulder. Chart generated by TheSky6 © Software Bisque, Inc.




UppsalaSchmidt.Siding SpringComet Siding Spring, C/2013 A1, passes close by Mars today at a distance of about 140,000km.



Comet Siding Spring was discovered with the Uppsala Schmidt telescope at Siding Spring Observatory on January 3, 2013. Photo by Robert McNaught/RSAA.








Daily cosmobite: Mercury reaches inferior conjunction today

Published by Andrew Jacob on October 17, 2014 No Comments

Messenger.Mercury.NASA.pia17397Today the innermost planet, Mercury, passes between Earth and the Sun. This is referred to as an “inferior conjunction”. It will next be visible into the pre-dawn sky at the end of this month.



The Messenger spacecraft continues to monitor Mercury. The butterfly pattern of this crater’s ejecta results from a very shallow impact. Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.





Daily cosmobite: Happy 40th Birthday AAT!

Published by Andrew Jacob on October 16, 2014 No Comments

AAT40thStarFest2014.AJThe Anglo-Australian Telescope (AAT), Australia’s largest optical telescope, was officially opened 40 years ago on October 16, 1974 by Prince Charles. Happy Birthday!




The Anglo-Australian Telescope dome all wrapped up for its birthday celebrations during StarFest, October 4, 2014. Photo © Andrew Jacob






Daily cosmobite: Warrumbungles view from Mt Woorut

Published by Andrew Jacob on October 15, 2014 No Comments

P3549-272Harley Wood’s site searching eventually resulted in the selection of Mt Woorut as the site for the Siding Spring Observatory.


The view into the Warrumbungle National Park from Mt Woorut, c1959.

HWetal.KadinaTrigParkesHarley Wood, NSW Government Astronomer, inspected sites across NSW in 1958 to find a suitable location for a new telescope. The man on the right in this photo is Dr Alex Rodgers from Mt Stromlo Observatory [may be J. Schilt of Columbia University, USA.]

Harley Wood (middle) site searching in 1958 at Kadina trig near Parkes, NSW.







Daily cosmobite: The Earth is a sphere

Published by Andrew Jacob on October 13, 2014 No Comments

TLE08OCT2014.latepartialphaseAristotle, the ancient Greek philosopher, is said to have used the curved shadow of Earth seen during a lunar eclipse to support his theory of a spherical Earth. Modern measurements show Earth is slightly pear-shaped and knobbly.



The Earth’s shadow had a curved edge when seen during the lunar eclipse of October 8, 2014. Image ©MAAS.



A bird’s eye view of the eclipse over Sydney

Published by Melissa Hulbert on October 11, 2014 No Comments

Wednesday night saw the second of a tetrad of lunar eclipses. The evening was not clear with two layers of cloud moving in from different directions, but fortunately there were some occasional gaps in the cloud cover providing glimpses of the Moon.
I spent the evening at the top of Sydney Observatory’s time ball tower with a wonderful view over Sydney hoping for some good views of the eclipse.
The start of the eclipse came and went with a short gap in the clouds about 8:30pm.

The Moon partially covered by the Earth’s shadow. Photo and copyright Melissa Hulbert ©, all rights reserved.

The Moon partially covered by the Earth’s shadow.
Photo and copyright Melissa Hulbert ©, all rights reserved.


The start of totality also came and went but at about 10:10pm gaps appeared in the clouds and the lovely red Moon popped out over Sydney.

Totality over Sydney.    Photo and copyright Melissa Hulbert ©, all rights reserved.

Totality over Sydney.
Photo and copyright Melissa Hulbert ©, all rights reserved.


Cries of “Here comes the Moon”, “Isn’t it beautiful” and “Oh wow” drifted up from visitors to Sydney Observatory.
A gap a little later allowed a few final glimpses of the so named “blood Moon” before the clouds again drifted over.
About 10:45pm the clouds started to part and the final phases of the eclipse were visible and great images obtained by Sydney Observatory’s live stream.

Despite the clouds it was still a beautiful eclipse, with each unique as you can never predict the exact colour at totality.
I’m looking forward to next year’s eclipse on 4th April, starting at 9:15pm with totality at 10:58pm.

The Moon during totality.    Photo and copyright Melissa Hulbert ©, all rights reserved.

The Moon during totality.
Photo and copyright Melissa Hulbert ©, all rights reserved.

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, making them far more common 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 two kinds of lunar eclipse – a partial (or penumbral) eclipse, and a total (or umbral) eclipse. Partial eclipses occur when the Moon falls in the partial shadow of the Earth (penumbra), and total eclipses when the Moon is completely covered by the dark part of our shadow (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.



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