Archive for the ‘Astronomy blog’ Category

The first successful rendezvous in space, of the Gemini 6A and Gemini 7 spacecraft, was in December 1965. This marked the beginning of many space rendezvous and demonstrated the potential for two spacecraft to dock in orbit.  The two craft were not equipped for docking but came within 1 foot (or approx. 30cm) of each other, which is very close!

Today’s Cosmobite is by Sam Knox, an astronomy guide at MAAS – Sydney Observatory.

Gemini 7

Gemini 7 from Gemini 6A, in low Earth orbit. Photo courtesy NASA.


Daily Cosmobite: Pleiades

Published by Toner Stevenson on December 10, 2014 No Comments

The Pleiades or also known as the Seven Sisters is an open cluster system consisting of approximately 3000 stars. Pleiades has 9 bright stars, 7 named for the daughters and 2 for the parents in Greek Mythology. Interesting fact Pleiades means “Subaru” in Japanese, so next time you see a Subaru commercial look at it’s logo.  The Pleiades are prominent in the night sky and have many stories associated with them, including those told by Aboriginal Peoples.

This Daily Cosmobite was written by Paul Clemens. Paul is an astronomy guide at Sydney Observatory and he is a guide for the Powerhouse Museum’s Mars Lab.


A color-composite image of the Pleiades from the Digitized Sky Survey
Credit: NASA/ESA/AURA/Caltech

Transit of Venus 1874

Henry Chamberlain Russell’s observations of  the 1874 transit of Venus.

On 9 December 1874 a rare astronomical event occurred – the transit of Venus.  This involves Venus passing directly between the Earth and the Sun.

The Government Astronomer of the day (Henry Chamberlain Russell) decided that NSW would take a major role in the observation of this rare event.   Senior scientists of the NSW establishment took part in the observations which involved accurate timing of the entry and exit of the disk of Venus upon the Sun’s disk.   The observations involved timing four contacts where the leading and trailing edges crossing the sun were timed.   The aim of the observations was to enable calculation of the length of the Astronomical Unit (the distance between the Sun and the Earth)

Observations were carried out at various places throughout NSW – at Bega on the far south coast, Goulburn in the Southern Tablelands and Woodford in the Blue Mountains.  The most extensive observations were carried out at Sydney Observatory and included sketch images of the entrance and exit of Venus’s silhouette on the face of the Sun

Henry Chamberlain Russell achieved a grant from the NSW Government which he used to purchase the South Dome Refractor at Sydney Observatory.  Thus it can be said that the South Dome Refractor is also 140 years old and reputedly the oldest telescope still in use in Australia.  As such it is a major museum piece and is popular with members of the public for viewing the moon, bright planets and stars.

Inside Sydney Observatory there is an exhibition about this important 1874 transit of Venus. You can see this for free entry 10am to 5pm daily or on your booked night tour.

This post was written by astronomy guide and engineer, Col Draper. You can meet Col on a guided daytime tour at Sydney Observatory.

©Geoff Wyatt

Geoff Wyatt won the David Malin Awards for astrophotography with this image of the 2004 transit of Venus © Geoffrey Wyatt



The brightest star in the night sky award belongs to Sirius.  It rises around 8:40pm  and is part of the constellation Canis Major rising in the southeast in the night sky.  With an apparent magnitude of -1.46 it doubles the next brightest star in comparison called Canopus with an apparent magnitude of -.72. Sirius is nicknamed the Dog Star which means “Glowing” in Greek. ‘Sirius’ is also the name given to ‘Sirius Black’ in the book Harry Potter, and his character is very mysterious.

This post is by Sydney Observatory astronomy guide, Paul Clemens. You can meet Paul on day or night tours and he is often working at the Powerhouse Museum on the Mars Lab program.


Credit: NASA, H.E. Bond and E. Nelan (Space Telescope Science Institute, Baltimore, Md.); M. Barstow and M. Burleigh (University of Leicester, U.K.); and J.B. Holberg (University of Arizona)

This is the seventh post 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 and we plan to open the project late January 2015, with public tours from February 2015, thanks to funding from the NSW Department of Ageing Disability and Home Care. The project is being managed for MAAS by Adam Adair of Pure Projects and our builders are Zadro Constructions. The building was designed by NSW Government Architects Angus Donald, Vivian Sioutas and Terry King.  The dome will 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 Harley Wood and was operational from 1952.

Astrograph Dome

Education Program Manager , Geoff Wyatt, inspecting the dome. 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. 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 will feature in the display inside the new building. 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 6 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.

DFM telescope for Sydney Observatory

Greg Stevens, DFM engineer machinist, with our new partially assembled telescope. Photo K. Melsheimer

The big excitement over the past weeks has been all about the new telescope. Kate Melsheimer, from DFM telescopes in Colorado USA, sent us images of the telescope under assembly in their workshop.

In the image right you can see Greg Stevens, DFM engineer machinist, with the partially assembled telescope. This image was taken before they had installed the primary mirror in its cell and attached the mirror cell to the bottom of the white tube. They then installed the secondary mirror and Focus Housing to the top of the white tube and attached the control system cables to the telescope and performed function tests.

DFM Telescope for Sydney Observatory

DFM electronic technician, Jack Labbe, performing some software tests. Photo K. Melsheimer

The second image right shows DFM electronic technician, Jack Labbe, performing some software tests using the control system and hardware with DFM’s in-house demo mount. Before the telescope was packed it was tested during the night. The telescope was carefully packed, with its computer, mount and tubes.  It was then airfreighted to Sydney Airport via Hawaii. There were a few tense days while the crate sat at Honolulu airport, then relief when it safely arrived when we took delivery of the telescope which had travelled all the way from Colorado, USA.


Crate in MAAS workshop Sydney. Photo S. McMunn

You can get some idea of the size of the box that holds the telescope and is now  in the MAAS Conservators workshop from the photograph taken by prject manager Susan McMunn. This was sent to Kate back at DFM to reassure her that all was well.

For the base build team the past month has been all about the details and making sure the building is ready for the DFM telescope and the arrival of Mark from DFM who is going to assemble and commission the telescope.

The roof is on and the building is now rendered, we are very fortunate that this happened before the past many days of fierce storms and heavy rain. The dome now has a finished floor and the lift for wheelchair users was installed last week. The electrical, lighting and data connections have now been positioned ready for connection.  Some minor adjustments to the location of services by Zadro Constructions meant Sydney Observatory have created a great space for future signage.

East Dome building under construction

This image shows the East Dome building with its roof, and recently rendered walls. Photo T.Stevenson.



December 2014 night sky guide podcast, transcript and sky chart

Published by Sydney Observatory on November 26, 2014 No Comments

Geoff Wyatt operating the telescope in the north domeTo 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 Geoffrey Wyatt, Astronomy Educator at Sydney Observatory (pictured at right).

Among Geoff’s recommendations for viewing in the southern sky this month are Fomalhaut, the brightest star in Piscis Austrinus (the Southern Fish), Achernar, the brightest star in Eridanus (the River), Orion (the Hunter) within which you can find the beautiful nebula, M42, and Aldebaran, the brightest star in Taurus (the Bull). He also tells you where to find the Large and Small Magellanic Clouds.

Geoff’s engaging presentation includes fascinating ancient Greek and even more ancient Indigenous astronomical mythologies. And don’t forget to look out for the Geminid meteor shower on 14th and 15th December. For this and more, listen to the December 2014 night sky guide audio, or read the transcript below.

You can subscribe with iTunes or upload the (42 mins 50 secs) audio to your iPod or mp3 player, or listen to it on your computer.

We provide an embedded sky map (below) and a starmapDec2014 (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.

December 2014 night sky chart

Our annual book’The 2015 Australasian sky guide’ by Dr Nick Lomb – this year the 25th edition of the book – 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).

READ THE TRANSCRIPT (after the jump)


Daily cosmobite: Fomalhaut’s dusty ring

Published by Andrew Jacob on November 21, 2014 No Comments

ALMA_Fomalhaut_01. ALMA/NASA/ESAThe brightest star in Piscis Austrinus is Fomalhaut. Images made by the Atacama Large Millimeter/submillimeter Array (ALMA) in 2012 revealed a narrow dusty ring probably constrained by a pair of unseen planets. That makes Fomalhaut one of about twenty naked-eye stars to host a multiple-planet system.


ALMA data, in orange, shows a dusty ring (partially imaged) around Fomalhaut. ALMA (ESO/NAOJ/NRAO). Visible light image in blue: the NASA/ESA Hubble Space Telescope



PiscisAustrinusPiscis Austrinus, the Southern Fish, is high overhead for southern hemisphere observers at present. It’s a challenge to discern the ‘fish’ shape but its brightest star, Fomalhaut, is easily seen with the naked eye.


Fomalhaut is the brightest star in Piscis Austrinus. Chart generated by TheSky6 © Software Bisque, Inc.




January 2015 is predicted to be hot, hot hot. So get out and about to Sydney Observatory and enjoy the evening telescope viewing, hearing amazing stories of the night sky and soaking up the atmosphere in one of the most important heritage and scientific sites in Australia. There are programs for families such as the Celestial Pizza nights, and romantic pre and post dinner programs for couples. Book before its too late.

Venus: goddess of love
23, 24, 25 Jan 6:30 to 8:15pm
Enjoy a glass of champagne and nibbles while observing the setting Sun and telescope viewing of Venus (weather permitting) whilst listening to live music in our gorgeous marquee.visitors
Cost: $35 per adult $32 concession and $30 members.

Telescope Express, viewing only
12, 14, 19, 22 Jan 9:30 to 10:30pm.
Telescope viewing only weather permitting, wet weather option is 3D Space Theatre and planetarium. Tickets are limited. This suits adults and high school students and older.
Cost: $50 family, $18 adult, $14 concession; Powerhouse members $43 family, $16 adult, $12 concession.

Dreamtime Astronomy : planetarium and telescope tours
7:30 to 8:30pm, Tuesdays, Fridays and Saturdays
Hear stories written across the Australian sky as out Aboriginal Guides share their cultural astronomy under the virtual night sky in the planetarium. Then view objects through the telescope.
Cost: $50 family, $18 adult, $12 child; Powerhouse Members $43 family, $16 adult, $11 child.
BOOK NOWRomantic sunset photo Geoff Wyatt

Celestial Night Tour
8:30 to 10pm. Bookings and prepayment required.
View Orion the Hunter, Taurus the Bull and Canis Major the Great Dog and, at the beginning of the month, the Moon (first week of Jan only), amongst other celestial features through telescopes and experience the new ‘Telescopes’ 3D Space Theatre program. Cost: $50 family, $18 adult, $12 child; Powerhouse Members $43 family, $16 adult, $11 child.BOOK NOW! or phone 02 9921 3485 during office hours (8:30am – 4:30pm) to avoid disappointment. Please read our conditions before booking a tour.

Celestial Pizza Nights
12, 14, 19, 22 Jan 7:30 to 8:15pm
These special nights of pizza, astronomy stories and telescope viewing (weather permitting) are especially for young families.
Cost: $30 adult, $27 concession, $25 child (4 years+), $85 family. MAAS members $25 adult, $22 conc, $20 child, $72 family

NASA.GSFC.dmr_4yr_cmb_stereoThe Cosmic Background Explorer (COBE) satellite was launched 25 years ago on 18 September, 1989. It showed that the cosmic microwave background, the cold afterglow of the Big Bang, was not completely uniform. Tiny temperature fluctuations visible in this “map” have grown into enormous galactic structures in the intervening 14 billion years.



COBE made this “map of the early universe” showing tiny variations in the cosmic microwave background. NASA/GSFC






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