Archive for the ‘Astronomy blog’ Category

ESO/G. Brammer.MWHorizon.potw1412aIn Spring evenings the Milky Way forms a ring around the horizon, as seen from Australia. At midnight on Halloween look up (or is it down?) and you have a clear view to the universe. Out there countless galaxies hurtle away from you in the expanding universe and far away is the cosmic background radiation – the residual glow of the Big Bang.


Paranal observatory and the Milky Way on the horizon. ESO/G. Brammer.





Daily Cosmobite: Centenary of Sir David Gill’s death

Published by Andrew Jacob on October 29, 2014 2 Comments

David_Gill.wikiSir David Gill died in 1914. Among many achievements he took a photo of the “Great Comet” of 1882. The appearance of previously unseen stars in the background spurred two projects, the Astrographic Catalogue and the Carte du Ciel, to catalogue and map the entire sky using photography.





Sir David Gill.  Lick Observatory collection via wiki.

Daily Cosmobite: Moon and Mars in the west

Published by Andrew Jacob on October 28, 2014 No Comments

MoonMars28Oct2014Tonight look for the Moon and Mars in the west. At 8pm the crescent Moon will be two hand-spans (at arm’s length) above the horizon with orange-red Mars a fist-width above and to the left. The Moon’s light takes 1.3 seconds to reach you while light from Mars tonight takes 13.9 minutes.


The Moon and Mars in the west on October 28 2014.  Chart generated by TheSky6 © Software Bisque, Inc.






Daily cosmobite: The Spare-Tyre nebula in Grus

Published by Andrew Jacob on October 27, 2014 1 Comment

IC5148.ESO.wikiConstellation Grus contains the “Spare-Tyre” nebula, a beautiful planetary nebula. A planetary nebula is the final death-throws of a Sun-like star that has shed its outer layers in a final dying gasp. This one is 3000 light years away.



The “Spare-Tyre” nebula in Grus, IC5148. Courtesy of ESO/wiki.






To help you learn about the southern night sky, Sydney Observatory provides an audio guide/podcast, transcript of that audio, and a sky map or chart each month. This month’s guide is presented by Melissa Hulbert, Sydney Observatory Astronomy Educator.

In the November sky guide, as well as showing us where to find the constellations Pegasus, Orion and Taurus, and the star clusters, Hyades and Pleiades, Mel tells us the best times to see the bright planets Venus and Jupiter.

Mel also tells us where we can hope to see Comet C/2012 K1 PanSTARRS during November. For this and more, listen to the November 2014 night sky guide audio, or read the transcript below.

You can subscribe with iTunes or upload the (16 minutes 46 seconds) audio to your iPod or mp3 player, or listen to it on your computer.

We provide an embedded sky map (below) and a November 2014 night sky chart (PDF) which shows the stars, constellations and planets visible in the night sky from anywhere in Australia. To view PDF star charts you will need to download and install Adobe Acrobat Reader if it’s not on your computer already.

November 2014 night sky chart

Our annual book, ‘The 2015 Australasian sky guide’ by Dr Nick Lomb has more information and star maps for months from December 2014 until December 2015 inclusive, plus information about the Sun, twilight, the Moon and tides, and a host of other fascinating astronomical information. You can purchase it ($16.95) at Sydney Observatory and Powerhouse Museum shops or other good bookshops, or online through Powerhouse Publishing (additional packing/postage costs apply). The 2015 edition, which will be the 25th anniversary edition, is now available!

READ THE TRANSCRIPT (after the jump)


This is the fifth 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 two weeks this future progressed and an important delivery was successfully made. Building works are still on schedule for completion by Christmas.  The installation and commissioning of the new accessible DFM telescope with the revolutionary Articulated Relay Eyepiece was locked in and the exhibition will be installed leading up to a grand opening late January 2015.

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. In blog 4 I confirmed the name ‘East Dome’  and that the concrete pour had been successful and bricks and block-work walls were progressing.

Astrographic telescope

John Winter, project Manager Zadro Constructions, and Danny grant MAAS facilities Manager , inspect the dome brickwork and ring beam.

This past week the brick and block walls have reached their final heights. The circular brickwork, which forms the base of the dome, was impeccably laid by the builders, Zadro Constructions.  The steelwork ring beam was installed and inspected by the engineer. This is very important because it has to support the copper dome which will be delivered soon.  We can now get a feel for inside the dome, where the lift and stairs will be located. It was good to get a sense of how much area we will have inside the dome for the telescope, the astronomer and the public, some of whom will be in wheelchairs. Look carefully at the photograph above and you can see a rectangular shape on the floor of the dome. This is a separated piece of concrete on which the telescope pier will sit, isolated from any floor vibration. Astronomy curator, Dr Andrew Jacob, has been involved in the project and checking the construction to ensure it will suit our purposes as a public observatory.



Render is applied to the block-work interior wall.

The concrete block-work wall, which delineates the dome from the foyer and exhibition  building, was completed and the electrical wires for power and lighting were roughed in. We were all impressed by the rendered finish of this wall once it was complete and the cement had cured to an even finish.

Friday morning my excitement was hard to contain as we waited for the delivery of the mount for the 13″ refracting astrographic telescope. This telescope and its mount was made by Howard Grubb and Sons in Dublin, Ireland. It was one of eight telescopes made for the international Carte du Ciel ( chart of the sky) and Astrographic Catalogue (star catalogue) projects. It was originally delivered to Melbourne Observatory on 29 December, 1890.  The telescope was purchased by Sydney Observatory in the late 1940s when Melbourne Observatory closed. In 1952 the Astrograph was installed in a new building constructed by the Government Architects branch to the specifications of NSW Government Astronomer, Harley Wood. The telescope was then used to complete the photography of the Sydney zone for the Astrographic Catalogue and take a few replacement photographs for the Melbourne zone. The telescope was operated regularly to complete the Astrographic Catalogue , it was then used to photograph the Southern Sydney Star Catalogue and, when Sydney Observatory ceased astronomical research, amateur astronomers used it to photograph comets and other celestial objects. In 1986 the telescope was transported to Macquarie University and stored until 2008. Over the past 12 months the Museum of Applied Arts and Sciences(MAAS) Conservators, Tim Morris and Carey Ward, with the assistance of expert volunteers,  have restored the telescope.

Astrographic telescope

Carey Ward, Toner Stevenson, Geoff Wyatt are very happy to see the return of the Grubb Astrographic Telescope.

The mount was delivered on a flat bed truck and then craned into place very very carefully. Carey, who was an instrument maker at Sydney Observatory from 1980 to 1982, worked with MAAS carpenter, Barry, and MAAS steam engine mechanic, Ralph, to transport the instrument mount and then safely install it. Once installed it was wrapped and then boxed so it will be protected during the completion of building works. The operation took considerable planning by the project management team Danny Grant, Sue McMunn and Adam Adair, and was successfully and safely completed. You can see from the photographs that there are no telescope tubes installed yet. These are still back at the museum workshop. The telescope tubes will be installed before the glass walls are completed because these are also of considerable weight and difficult to manouevre. Once the building work is complete, then the lenses and photographic apparatus will be attached. This will complete the telescope for display.


The Astrograph mount is carefully manoeuvred into place by Carey, Ralph and Barry.

The next step is to get the roof on and more of the walls up and, if progress is made as planned, in the next blog I will be writing about the delivery and installation of the historic dome.





Today marked the start of the Solar Eclipse Conference 2014 in New Mexico. The first two days of the four day conference focus on education and are being hosted by the Sacramento Peak Observatory.

In the morning we heard from Ralph Chou on eclipse safety and some of the new statistics on eye damage caused by not properly observing the Sun and Fred Espenak who spoke about what he has learned over many years of eclipse chasing, some of the do’s and don’ts with imaging.

Fred Espenak speaking on "Photographing Eclipses".  Photo and copyright Melissa Hulbert ©, all rights reserved.

Fred Espenak speaking on “Photographing Eclipses”.
Photo and copyright Melissa Hulbert ©, all rights reserved.

The afternoon was devoted to the partial solar eclipse and everyone setup cameras, telescopes, binoculars and solar glasses to observe to eclipse and a wonderful sunspot, which is said to be the largest since 1988. In fact the sunspot looks so good, even just through solar glasses that it almost over shadowed the eclipse!

There were a few clouds around during the day but by late afternoon the skies were clear and a clear view of the eclipse and the spectacular sunspot made for very happy eclipse chasers! Maximum eclipse saw just over 43% of the Sun covered by the Moon. Our observing site was next to the Dunn Solar Telescope  and being one of the highest points around (about 2800m above sea level) provides impressive views across the valleys.

Many might ask why a partial is interesting given its not total or annular eclipse? Partial eclipses all appear differently especially when sunspots are present and t also gives eclipse chasers (also known as Umbraphiles) a chance to test new gear and equipment setups ready for the next total/annular eclipse.

Maximum Eclipse. Photo and copyright Melissa Hulbert ©, all rights reserved.

Maximum Eclipse.
Photo and copyright Melissa Hulbert ©, all rights reserved.

If you have solar glasses (or specialised filters for your telescope/binoculars) then take a look at the magnificent sunspot. Otherwise, if you don’t have specialised solar viewing equipment then drop into Sydney Observatory and do a tour that includes viewing through the telescopes (weather permitting) over the next few days – this sunspot is really worth a look!














Antikythrera mechanismThe appearance of eclipses is governed by the Saros cycle, a long sequence of eclipses occurring at 18 year intervals. Today’s eclipse is part of Saros 153 and many cycles are in play at any one time. Australia will not see an eclipse in the Saros 153 cycle until the year 2501!


The remarkable Antikythera mechanism had the Saros cycle programmed into its gearing to  predict eclipses.





24 Oct 2014 Daily cosmobite : Partial solar eclipse

Published by Andrew Jacob on October 23, 2014 No Comments


A partial solar eclipse occurs on the morning of Friday October 24, 2014 AEDT . It is only visible from far eastern Russia, Canada, USA and Mexico but you can view it via live streams from Griffith Observatory, LA and SLOOH. Both streams begin at 8am AEDT.

*Full eye-safety precautions are required if you are viewing this eclipse in person.


The partial solar eclipse of October 24 2014 (AEDT) as seen from Los Angeles. The Moon partially covers the Sun. Chart generated by TheSky6 © Software Bisque, Inc.

Daily cosmobite: Constellation Grus, the Crane

Published by Andrew Jacob on October 22, 2014 No Comments

GrusThe constellation Grus, the Crane, is high overhead at present. It first appeared on a celestial globe by Petrus Plancius in 1598. It is one of nine celestial birds but it looks more like a scimitar to me.






Grus, the Crane. Chart generated by TheSky6 © Software Bisque, Inc.







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