ASTRONOMERS ARE HUNTING ‘FOSSIL’ STARS FROM GALAXIES DEVOURED BY THE MILKY WAY CREDIT: HUBBLE HERITAGE TEAM (AURA/STSCI/NASA/ESA)
Ken Freeman is hunting for fossils. But he’s not looking for old bones—he’s exploring the very origin and history of our Milky Way galaxy.
Conventional theory says that our galaxy grew big by engulfing smaller ones. If this is correct, stars from the original galaxies should be still identifiable within the main mass of stars via several tell-tale signs, from unusual velocities to spectral types. These stellar fossils would point to the galaxy’s birth and growth. Continue reading Galactic archaeology— digging into the Milky Way’s past→
THE RED RECTANGLE IS A PECULIAR NEBULA WITH SOME STRANGE CHEMICAL PROPERTIES. CREDIT: NASA/ESA/ HANS VAN WINCKEL (CATHOLIC UNIVERSITY OF LEUVEN) /MARTIN COHEN (UCB).
Cracking the puzzle of unusual molecules in deep space that absorb some wavelengths of starlight is like unlocking the secrets of the Rosetta Stone, according to Rob Sharp of the Australian National University’s Research School of Astronomy and Astrophysics. “It’s the longest-standing problem in astronomical spectroscopy,” he says.
The Giant Magellan Telescope may use Australian Starbugs technology when it begins operating in around 2018. Credit: Giant Magellan Telescope—GMTO Corporation
Imagine an extremely large optical telescope fitted with detectors that can selectively collect light from a particular section of the telescope’s focal plane. Using revolutionary robotic technology called Starbugs, the detector will reconfigure itself in real time to collect from any particular area of the image, and will feed the data into any analytical instrument.
That’s exactly what Matthew Colless and his team at the Australian Astronomical Observatory have in mind with the development of MANIFEST (the many-instrument fibre system)—which make use of the special photonic technologies developed by Joss Bland-Hawthorn and his team at the University of Sydney. Continue reading Sifting sky data→
LAUNCHING THE KEPLER SPACE TELESCOPE. CREDIT: BALL AEROSPACE AND TECHNOLOGIES CORP.
Stars forming in clusters from a single galactic dust cloud are not as similar to one another as previously thought, according to an international team of astronomers who analysed ‘starquakes’ from just three months of data from NASA’s Kepler space telescope. And there is at least another four years’ data to come.
“In the past, it was assumed that the only difference [between stars in the same cluster] would be their mass,” says Dennis Stello of the University of Sydney. “But the seismology [data] tells us that might not be correct. There’s probably a spread in age or in composition because the original cloud of gas was not homogeneous.” Continue reading Starquakes reveal family secrets→
JOSS BLAND-HAWTHORN HOLDING A PHOTONIC LANTERN, A REVOLUTIONARY DEVICE TO ANALYSE THE LIGHT OF DISTANT STARS, INVENTED IN AUSTRALIA. CREDIT: CHRIS WALSH.
Using the Gemini South telescope in Chile, a team of astronomers led by Joss Bland-Hawthorn of the University of Sydney revealed the faint, outer regions of the galaxy called NGC 300, showing that the galaxy is at least twice the size as thought previously. The findings suggest that our own Milky Way galaxy could also be bigger than the textbooks say.
But Joss’s telescope observations are just a part of his contribution to astronomy. He is also helping to pioneer a new technology known as astrophotonics, which uses optical systems to improve our understanding of the Universe. Continue reading Bringing dark corners of the Universe to light→
SUSI AT NARRABRI—ONE OF THE HIGHEST SPATIAL RESOLUTION TELESCOPES USING VISIBLE LIGHT. CREDIT: GORDON ROBERTSON.
When the present upgrade is complete, the Sydney University Stellar Interferometer (SUSI) will be able to resolve objects the size of a beach ball on the Moon, says Mike Ireland of Macquarie University in Sydney. This large interferometer will be used to determine the dimensions—size, weight and velocity—of pulsating stars, hot stars, and massive stars. SUSI will also be involved in the search for binary stars and their planetary companions. Continue reading Seeing a beach ball on the moon→
A FALSE-COLOUR COMPOSITE IMAGE OF 11 FRAMES SHOWING THE 8-MONTH CIRCULAR ROTATION OF THE BINARY STAR, WOLF-RAYET 104. CREDIT: PETER TUTHILL.
It seems counterintuitive, but restricting the amount of light that reaches a telescope can sharpen up its output. The technique will be used on NASA’s successor to the Hubble Space Telescope: the James Webb Space Telescope. But it is already proving its worth here on Earth.
Images of the binary star known as Wolf-Rayet 104 (WR104), published in 2008 by Peter Tuthill of the University of Sydney, reveal the power of the new technique, which is known as aperture masking. WR104 should be difficult to see because it is in a deep cloud of dust, but Peter and his colleagues used aperture masking when observing the star with the Keck telescope in Hawai’i. The mask leads to sharper images because it cuts down complexity and makes the data easier to process and rid of error. Continue reading Keck telescope dons a mask→
THIS SATELLITE LASER RANGING STATION MANAGED BY GEOSCIENCE AUSTRALIA AT MOUNT STROMLO OBSERVATORY NEAR CANBERRA WAS BUILT AND IS OPERATED BY EOS. CREDIT: CRAIG ELLIS.
An Australian company, Electro-Optic Systems (EOS), is one of the biggest developers of large, high-precision, optical research telescopes in the world. In fact, EOS has designed, built and installed the SkyMapper telescope and its enclosure at Siding Spring Observatory in New South Wales.
The headquarters of EOS is at the Mt Stromlo Observatory near Canberra, but its reach is international. Equipment the company has installed include the University of Tokyo’s two-metre telescope at Mount Haleakala, Hawai’i, a two-metre telescope in the Himalayas for the Indian Institute of Astrophysics, and the 2.4 metre Advanced Planet Finder (APF) at the University of California’s Lick Observatory. Continue reading Australian company brings the Universe within range→
SIDING SPRING MOUNTAIN’ IS HOME TO OVER A DOZEN AUSTRALIAN AND INTERNATIONAL TELESCOPES. CREDIT: FRED KAMPHUES.
Australia’s first observatory was built on the shores of Sydney Harbour by Lieutenant William Dawes of the First Fleet, on the point where the southern pylon of the Sydney Harbour Bridge now stands. Optical astronomy was essential for maritime navigation, and for providing precise location measurements for surveying the new continent.
The country’s first major observatory was established in 1821 at Parramatta by Thomas Brisbane, Governor of New South Wales and, later, President of the Royal Society. The observatory was used to discover and record the galaxy NGC 5128—a now much-studied galaxy that radio astronomers know as Centaurus A, within which sits a super-massive black hole (seeRecording the impact of a super-massive black hole). Continue reading From mapping a continent to surveying the Universe→
THE 3.9 METRE ANGLO-AUSTRALIAN TELESCOPE IS COLLECTING OPTICAL GALAXY DATA FOR THE GAMA SURVEY. CREDIT: BARNABY NORRIS.
A new ‘super survey’ is producing the largest database of galaxy measurements, spanning the last five billion years of cosmic history. The International Galaxy and Mass Assembly (GAMA) project is combining data from ground-and space-based observatories to measure the ‘haloes’ of dark matter that surround galaxies.
“The Cold Dark Matter (CDM) model of cosmology makes predictions about how galaxies cluster and, in many cases, collide and merge,” says Andrew Hopkins, a GAMA team member. “Our measurements of the speeds of galaxies will reveal the distribution of dark matter, and enable us to test the CDM model.”
