All posts by Niall

Bringing dark corners of the Universe to light

JOSS BLAND-HAWTHORN HOLDING A PHOTONIC LANTERN, A REVOLUTIONARY DEVICE TO ANALYSE THE LIGHT OF DISTANT STARS, INVENTED IN AUSTRALIA. CREDIT: CHRIS WALSH.
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

Seeing a beach ball on the moon

SUSI AT NARRABRI—ONE OF THE HIGHEST SPATIAL RESOLUTION TELESCOPES USING VISIBLE LIGHT. CREDIT: GORDON ROBERTSON.
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

Keck telescope dons a mask

A FALSE-COLOUR COMPOSITE IMAGE OF 11 FRAMES SHOWING THE 8-MONTH CIRCULAR ROTATION OF THE BINARY STAR, WOLF-RAYET 104. CREDIT: PETER TUTHILL.
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

SkyMapper’s 268-megapixel camera

On a mountaintop in northern New South Wales sits a new telescope equipped with Australia’s largest digital camera. The Australian National University’s (ANU) SkyMapper facility has been established at Siding Spring Observatory to conduct the most comprehensive optical survey yet of the southern sky.

Fully automated, the telescope is measuring the shape, brightness and spectral type of over a billion stars and galaxies, down to one million times fainter than the eye can see.

SKYMAPPER AT SIDING SPRING, NORTHERN NEW SOUTH WALES. CREDIT: AUSTRALIAN NATIONAL UNIVERSITY.

Continue reading SkyMapper’s 268-megapixel camera

Australian company brings the Universe within range

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.
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

Mount Stromlo Observatory rising from the ashes

THE ENCLOSURE OF THE GIANT 8.1-METRE GEMINI SOUTH TELESCOPE AT CERRO PACHÓN IN THE ANDES MOUNTAINS. CHILE. CREDIT: GEMINI OBSERVATORY.
THE ENCLOSURE OF THE GIANT 8.1-METRE GEMINI SOUTH TELESCOPE AT CERRO PACHÓN IN THE ANDES MOUNTAINS. CHILE. CREDIT: GEMINI OBSERVATORY.

The Mount Stromlo Observatory of the Australian National University (ANU) is rising from the ashes of Canberra’s 2003 bushfires, after an investment of millions of dollars into cutting-edge technologies and facilities.

The Mount Stromlo site—home to the ANU’s Research School of Astronomy and Astrophysics (RSAA)—no longer acts as a research observatory, but rather as a high-tech hub developing astronomical instruments for the world’s most advanced telescopes. Staff at the RSAA’s Advanced Instrumentation and Technology Centre have already built multi­million dollar instruments, such as the Near-Infrared Integral-Field Spectrograph (NIFS) for the Gemini North Telescope which provides images in the infrared equivalent to the Hubble Space Telescope in the optical range. Continue reading Mount Stromlo Observatory rising from the ashes

From mapping a continent to surveying the Universe

SIDING SPRING MOUNTAIN’ IS HOME TO OVER A DOZEN AUSTRALIAN AND INTERNATIONAL TELESCOPES. CREDIT: FRED KAMPHUES.
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 (see Recording the impact of a super-massive black hole). Continue reading From mapping a continent to surveying the Universe

Measuring the Universe from start to finish

THE HUBBLE SPACE TELESCOPE CAN BE USED TO TAKE MEASUREMENTS THAT WILL HELP ANSWER SOME OF THE BIGGEST QUESTIONS ABOUT THE UNIVERSE. CREDIT: NASA/STSCI.
THE HUBBLE SPACE TELESCOPE CAN BE USED TO TAKE MEASUREMENTS THAT WILL HELP ANSWER SOME OF THE BIGGEST QUESTIONS ABOUT THE UNIVERSE. CREDIT: NASA/STSCI.

Scientific puzzles don’t come much bigger than these. How old is the Universe? How big is it? And what is its ultimate fate?

A single number, Hubble’s constant, is the key that can unlock all of those questions, but it’s a number that has proved notoriously hard to accurately measure. Hubble’s constant is the rate at which the Universe is expanding. The first team to accurately make that measurement was co-led by Jeremy Mould, now a professor at Swinburne University of Technology and professorial fellow at the University of Melbourne. Continue reading Measuring the Universe from start to finish

Ten times more galaxies

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.”

Continue reading Ten times more galaxies

Spinning galaxies reveal missing matter

PHOTO: DARK MATTER DOMINATES GALAXIES AND GROUPS OF GALAXIES, YET ITS IDENTITY REMAINS UNKNOWN. CREDIT: DAVID MALIN, AUSTRALIAN ASTRONOMICAL OBSERVATORY.
PHOTO: DARK MATTER DOMINATES GALAXIES AND GROUPS OF GALAXIES, YET ITS IDENTITY REMAINS UNKNOWN. CREDIT: DAVID MALIN, AUSTRALIAN ASTRONOMICAL OBSERVATORY.

Australian astronomers have long been contributing to our understanding of a strange cosmological phenomenon—the Universe’s missing matter.

In the early 1970s, Ken Freeman of the Australian National University (ANU) determined that spiral galaxies must contain more matter than we can see. He postulated that dark matter—an invisible material first proposed 40 years earlier—must make up at least half the mass of these galaxies. Now, patches of dark matter are thought to be scattered across the Universe, playing a major role in holding galaxies and groups of galaxies together. Continue reading Spinning galaxies reveal missing matter