The south dome of Sydney Observatory is made from Muntz metal, a copper-zinc (brass) alloy. A stamp on the south dome showing this Muntz metal weighs 26 ounces per square foot. Photo by Toner Stevenson ©MAAS.
Galileo was born on this day, February 15, in 1564. Happy Birthday Galileo!
The Moon orbits Earth in 27.3 days. From the point of view of an observer on the ground it appears to move a little over 13-degrees eastward through the sky each night. This means it rises, on average, about 50-minutes later each night.
Several filaments, dark snake-like streaks, appear on the Sun today. These long streams of hot gas 'float in the magnetic field above the Sun's surface. APOD for 2015 Feb 10 claims one is amongst the longest ever recorded and it has been there for a week already.
Richard Hamming, mathematician, was born on Feb 11, 1915. Among other things he devised the Hamming window - a mathematical filter used in digital signal processing, whose name will be recognised by many engineers and physicists.
Light pollution is the bane of city-based astronomers. This series of night time images was taken from the International Space Station. They help identify dark sites from which to best view the sky. This week we look at Melbourne.
Until July Jupiter's moons will undergo a series of mutual eclipses and occultations. These happen every six years when the orbital plane of the moons appears edge-on to Earth. Jupiter's moons are clearly visible through the telescopes at Sydney Observatory.
In the 1850s plans were afoot to establish a time ball somewhere in Sydney. Captain Phillip Parker King recommended "...the ground about Fort Phillip because it is visible from all parts of the harbour and city".
Australia is part of the Giant Magellan Telescope project, one of the next-generation telescope projects currently in development. Its seven primary mirrors have an equivalent diameter of 24.5m. It will try to answer such questions as: Are we alone?
The constellation of Scorpius the scorpion in the southern winter sky. Image made with Stellarium In 2014 Dr Louise Pryke investigated the well-known zodiacal constellation of Taurus, the Bull. In her most recent research Dr Pryke has been exploring the ancient myth and astrological traditions surrounding the constellation Scorpius. When early humans first began to look up at the stars, and to tell stories about the great beings they saw among the constellations, scorpions had already inhabited the Earth for hundreds of millions of years.
To help you learn about the southern night sky, Sydney Observatory provides a guide to the night sky and a sky map or chart each month. This month's guide is presented by Melissa Hulbert, Sydney Observatory's Astronomy Programs Coordinator.
The Moon is full today. In the evening, around 9pm, look eastwards to see the full Moon with Jupiter just below and to the left. The full Moon and Jupiter are visible in the east with Gemini, the Twins, nearby.
Light pollution is the bane of city-based astronomers. However, night time images taken from the International Space Station help identify dark sites from which to best view the sky. Let's begin with Sydney.
Plate 694s was taken in 1893 from the grounds of Sydney Observatory with Russell's star camera. The star positions (X and Y) were measured in Melbourne. 442 stars were measured on this plate alone. Page 1 of volume 2 of the Sydney section of the Astrographic Catalogue. ©MAAS.
The 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.