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Weekly space gallery for January 28, 2014

WELCOME TO OUR WEEKLY COLLECTION of the best astronomy and space exploration images taken by observatories around the world and in space. Each week we’ll bring you a selection of our favourite recent images – if you like them (and we hope you do), please share them with your friends. And don’t forget you can elect to have this and other stories emailed direct to your inbox, just by signing up to our free email service – see the Subscribe box in the column at right.

So, let’s get started on this week’s images.

1. Disruptive black hole

A black hole lives at the heart of the white galaxy in the middle of this image. Extensive clouds of hot gas, detected by NASA’s Chandra X-ray Observatory satellite and coloured purple, should be the raw material from which countless new stars would be born. But jets of energy emanating from the vicinity of the black hole have disrupted the gas, forming two cavities on either side of the centre and sending out shock waves that prevent the gas from clumping and forming stars. The galaxy in question is called RX J1532+3201, and it is 3.9 billion light years from Earth. Image credit: X-ray: NASA / CXC / Stanford / J.Hlavacek-Larrondo et al, Optical: NASA / ESA / STScI / M.Postman & CLASH team.

Gas surrounding galaxy RX J1532+3201

Hot gas surrounds galaxy RX J1532+3201.


2. Titan, top and bottom

This black and white image of Titan, Saturn’s largest moon, was taken through a special infrared filter to bring out detail in its atmosphere. Visible at the far north (top) is a haze that stands up above the bulk of atmosphere, while near the south pole is the South Polar Vortex – thought to be an uplifted mass of air caused by a change in the seasons. This image was taken by NASA’s Cassini spacecraft from a distance of 2.5 million kilometres. Cassini has been orbiting Saturn since 2004. Courtesy NASA / JPL-Caltech / Space Science Institute.


Haze is visible in Titan’s north, while a polar vortex is in the south.


3. Brown dwarf revealed

Astronomers have used special techniques to block out the light of a star (leaving a speckled appearance) to reveal a dim brown dwarf that is in orbit around it. Brown dwarfs are bodies at are two big to be planets, but two small to be proper stars. They give off a relatively small amount of heat. The astronomers are particularly interested in studying the brown dwarf’s atmosphere, by analysing the light that reflects from it. “This object is old and cold and will ultimately garner much attention as one of the most well-studied and scrutinised brown dwarfs detected to date,” says Justin R. Crepp of the University of Notre Dame. “With continued follow-up observations, we can use it as a laboratory to test theoretical atmospheric models. Eventually we want to directly image and acquire the spectrum of Earth-like planets. Then, from the spectrum, we should be able to tell what the planet is made out of, what its mass is, radius, age, etc., basically all relevant physical properties.” Courtesy Crepp et al. 2014, ApJ.

Brown dwarf image

By blocking most of the light of its parent star, a faint brown dwarf is revealed.


4. A gallery of galaxies

The Hubble Space Telescope was used to make this long-exposure image of the galaxy cluster Abell 2744, which comprises the bright galaxies in the foreground. Fainter background galaxies appear to have become distorted as their light is bent by Abell 2744’s gravity. Astronomers have counted up to 3,000 of these background galaxies in the full-size version of this image alone. Courtesy NASA / ESA.

Galaxy cluster Abell 2744

A long Hubble exposure of galaxy cluster Abell 2744 also reveals other galaxies in the far background.


5. We have lift-off

NASA’s newest Tracking and Data Relay System Satellite (TDRSS) was launched on January 23 from the Kennedy Space Centre in Florida. There are several TDRSS satellites circling Earth, through which NASA can communicate with spacecraft in Earth orbit. They are not directly involved in communicating with deep space missions. Courtesy NASA / Tony Grey.

Time exposure of TDRSS launch

Lift off of NASA’s latest TDRSS satellite.


6. A supernova surprise

A supernova was spotted in galaxy M82 on January 21, causing great excitement amongst astronomers. M82 is only 12 million light years from Earth, making the supernova (called SN 2014J) one of the closest in many years. Many observatories broke into their normal scheduled operations to make observations of the supernova, including NASA’s Swift orbiting observatory. This picture, sensitive to ultraviolet light, shows the supernova standing out brightly against the amorphous background of the rest of M82. Courtesy NASA / Swift / P. Brown, TAMU.

Swift image of galaxy M82 and its supernova

A Swift image of galaxy M82 and its supernova.

Story by Jonathan Nally.

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GALLERY: Black holes galore

AN ASSORTMENT OF BLACK HOLES lights up a new image from NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR. Although the coloured blobs might not look like much, every one of them is a black hole located inside the hearts of a galaxy.

The different colours represent different energies of X-ray light. The red, yellow and green colours represent black holes seen previously by NASA’s Chandra X-ray Observatory (with red denoting the lowest-energy X-ray light). The colour blue shows black holes recently detected by NuSTAR, which is uniquely designed to detect the highest-energy X-ray light.

Image showing X-ray emission from black holes

Every one of the blobs you can see here, represents the location of a black hole. Although black holes cannot be directly seen, the X-ray light given off by hot gas in the vicinity can – and that’s what we see here; X-ray emission detected by the Chandra and NuSTAR space observatories.

The black holes in this picture are between about 3 to 10 billion light-years away.

The X-rays aren’t coming from the black holes themselves, since nothing can escape the gravitational grip of a black hole. Rather, they are coming from hot gas in the vicinity of the black holes.

Why do some black holes produce more high-energy X-ray light than others? Astronomers say this is because the black holes are more actively feeding off surrounding clouds of dust and gas – a process which heats up the gas and makes it emit X-rays.

The image shows an area, called the COSMOS field, that has been studied in great detail by many telescopes (COSMOS stands for Cosmic Evolution Survey). Red and green represent X-ray light seen by Chandra. Blue is for the kind of X-ray light that can only be seen by NuSTAR.

Adapted from information issued by NASA / JPL-Caltech / Yale University.

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Galactic explosion betrays black hole

TWO MILLION YEARS AGO a supermassive black hole at the heart of our galaxy erupted in an explosion so immensely powerful that it lit up a cloud 200,000 light years away, a team of researchers led by the University of Sydney has revealed.

The finding is an exciting confirmation that black holes can ‘flicker’, moving from maximum power to switching off over, in cosmic terms, short periods of time.

An artist's conception of a black hole generating a jet

An artist’s conception of a black hole generating a jet. Two million years ago the supermassive black hole at the centre of our Galaxy was 100 million times more powerful than it is today. Credit: NASA / Dana Berry / SkyWorks Digital

“For 20 years astronomers have suspected that such a significant outburst occurred, but now we know when this sleeping dragon, four million times the mass of the Sun, awoke and breathed fire with 100 million times the power it has today,” said Professor Joss Bland-Hawthorn from the University’s School of Physics, and lead author of an article on the research to be published in The Astrophysical Journal.

Professor Bland-Hawthorn unveiled the research at the international Galaxy Zoo science conference on 24 September in Sydney.

“It’s been long suspected that our Galactic Centre might have sporadically flared up in the past. These observations are a highly suggestive ‘smoking gun’,” said Martin Rees, Astronomer Royal, who was one of the first scientists to suggest that massive black holes power quasars.

Fossil record

The evidence for the findings comes from a lacy filament of hydrogen gas called the Magellanic Stream. It trails behind our galaxy’s two small companion galaxies, the Large and Small Magellanic Clouds.

“Since 1996, we’ve been aware of an odd glow from the Magellanic Stream, but didn’t understand the cause. Then this year, it finally dawned on me that it must be the mark, the fossil record, of a huge outburst of energy from the supermassive black hole at the centre of our galaxy.”

The region around the galaxy’s supermassive black hole and the black hole is called Sagittarius A* (pronounced Sagittarius A-star). It emits radio, infrared, ultraviolet, x-ray and gamma ray emissions. Flickers of radiation rise up when small clouds of gas fall onto the hot cloud of matter that swirls around the black hole.

The video below show a computer simulation of a black hole in real time showing how gas falling in forms a disc that spins around the black hole. The friction causes the gas to become so hot it produces beams of UV radiation. Credit: McKinney (UMD), Tchekhovskoy (Princeton), Blandford (KIPAC), Kaehler (KIPAC)

In stark contrast to this current inactivity, evidence is emerging that there was a cataclysmic event in the past.

“In particular, in 2010 NASA’s Fermi satellite discovered two huge bubbles of hot gas billowing out from the centre of the galaxy, covering almost a quarter of the sky,” said Professor Bland-Hawthorn.

On-and-off black holes

Earlier this year, computer simulations of the Fermi bubbles made by the University of California Santa Cruz controversially suggested that they were caused by a colossal explosion from Sagittarius A* within the last few million years.

“When I saw this research I realised that this same event would also explain the mysterious glow that we see on the Magellanic Stream,” Professor Bland-Hawthorn said.

“Together with Dr Ralph Sutherland from Mount Stromlo Observatory and Dr Phil Maloney, from the University of Colorado, I calculated that to explain the glow it must have happened two million years ago because the energy release shown by the Santa Cruz group perfectly matched, to our delight, that from the Magellanic Stream.”

“The galaxy’s stars don’t produce enough ultraviolet to account for the glow, nor could they have in the past,” said Dr Maloney. “The Galactic Centre never formed stars at a high enough rate. There had to be another explanation.”

Professor Bland-Hawthorn said, “In fact the radiation from stars is one hundred times too little to account for the radiation now or at any time. The galaxy could never have produced enough UV radiation to account for it. So the only explanation was it had to be produced from our dragon, the massive black hole.”

“The realisation that these black holes can switch on and off within a million years, which given the universe is 14 billion years old means very rapidly, is a significant discovery.”

Will such a colossal explosion ever happen again?

“Yes, absolutely! There are lots of stars and gas clouds that could fall onto the hot disk around the black hole,” says Professor Bland-Hawthorn. “There’s a gas cloud called G2 that astronomers around the world are anticipating will fall onto the black hole early next year. It’s small, but we’re looking forward to the fireworks!

Professor Bland-Hawthorn is a Fellow of the Australian Astronomical Observatory.

Adapted from information issued by the University of Sydney.

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Black holes grow faster than expected

Artist's impression of a black hole about to devour a star

Artist’s impression of a black hole about to devour a star. Supermassive black holes are thought to be at the heart of all major galaxies. Australian researchers have determined that as a galaxy grows, its black hole grows even faster.

  • Supermassive black holes have up to billions of times more mass than the Sun
  • How they became this big has been a long-standing mystery
  • Australia research shows big galaxies breed even bigger black holes

ASTRONOMERS FROM SWINBURNE UNIVERSITY of Technology in Australia have discovered how supermassive black holes grow – and it’s not what was expected.

For years, scientists had believed that supermassive black holes – millions or billions of times the mass of our Sun – located at the centres of galaxies, increased their mass in step with the growth of their host galaxy.  However, new observations have revealed a dramatically different behaviour.

“Black holes have been growing much faster than we thought,” Professor Alister Graham from Swinburne’s Centre for Astrophysics and Supercomputing said.

Within galaxies, there is a competition of sorts for the available gas; for either the formation of new stars or feeding the central black hole.

For more than a decade the leading models and theories have assigned a fixed fraction of the gas to each process, effectively preserving the ratio of black hole mass to galaxy mass. New research to be published in The Astrophysical Journal reveals that this approach needs to be changed.

“We now know that each ten-fold increase of a galaxy’s stellar mass is associated with a much larger 100-fold increase in its black hole mass,” Professor Graham said. “This has widespread implications for our understanding of galaxy and black hole co-evolution.”

The following animation depicts a star being devoured by a black hole.

Unexpected behaviour

The researchers have also found the opposite behaviour to exist among the tightly packed clusters of stars that are observed at the centres of smaller galaxies and in disc galaxies like our Milky Way.

“The smaller the galaxy, the greater the fraction of stars in these dense, compact clusters,” Swinburne researcher Dr Nicholas Scott said. “In the lower mass galaxies the star clusters, which can contain up to millions of stars, really dominate over the black holes.”

Previously it was thought that the star clusters contained a constant 0.2 per cent of the galaxy mass.

Black holes = gravitational prisons

The research also appears to have solved a long-standing mystery in astronomy. ‘Intermediate mass’ black holes with masses between that of a single star and one million stars have been remarkably elusive.

The new research predicts that numerous galaxies already known to harbour a black hole – albeit of a currently unknown mass – should contain these missing `intermediate mass’ black holes.

Artist's impression of a black hole in a star field

Intermediate or middle-sized black holes have proved elusive (artist’s impression).

“These may be big enough to be seen by the new generation of extremely large telescopes,” Dr Scott said.

Professor Graham said these black holes were still capable of readily devouring any stars and their potential planets if they ventured too close.

“Black holes are effectively gravitational prisons and compactors, and this may have been the fate of many past solar systems,” Professor Graham said. “Indeed, such a cosmic dance will contribute at some level to the transformation of nuclear star clusters into massive black holes.”

The researchers combined observations from the Hubble Space Telescope, the European Very Large Telescope in Chile and the Keck Telescope in Hawaii to create the largest sample to date of galaxies with reliable star cluster and supermassive black hole mass measurements.

Adapted from information issued by Swinburne University of Technology. Images by Gabriel Perez Diaz.

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Black hole to destroy cloud

  • Giant gas cloud about to enter black hole
  • The black hole is at the centre of our galaxy
  • Astronomers to watch it happen in 2013

THE BLACK HOLE AT THE CENTRE of the our galaxy, formally known as Sagittarius A* – pronounced Sagittarius A star – is about to unleash its destructive power. By mid-2013, a gas cloud is expected to pass in its vicinity at a distance of only 36 light-hours (equivalent to 40,000,000,000 km), which is extremely close in astronomical terms. The cloud will be ripped apart.

For the past 20 years, Stefan Gillessen, an astrophysicist at the Max Planck Institute for Extraterrestrial Physics in Munich, Germany, has been studying the black hole. “So far there have been only two stars [we have seen] that came that close to Sagittarius A*”, he says. “They passed unharmed, but this time will be different: the gas cloud will be completely ripped apart by the tidal forces of the black hole.”

A black hole is what remains after a supermassive star dies. When the “fuel” of a star runs low, it will first swell and then collapse to a dense core. If this remnant core has more than three times the mass of our Sun, it will transform to a black hole.

Direct observations of such black holes are impossible because they are coal-black and do not emit light or matter. But astronomers can identify a black hole indirectly due to the affect it has on objects in its vicinity.

So-called supermassive black holes are the largest type. Their mass equals hundreds of thousands to a billion times the mass of our Sun. The centres of all galaxies are thought to contain supermassive black holes. But their origin is not fully understood and astrophysicists can only speculate as to what happens inside them. Hence the imminent collision is of great interest, as it should provide some new insights.

Reinhard Genzel (European Southern Observatory) leads the team of astronomers that discovered the cloud and studied its trajectory. According to their observations, its speed has nearly doubled in the last seven years, reaching more than 8 million km/h.

The cloud’s edges have already started to shred and it is expected to break up completely over the coming months. As it nears the collision, the cloud is expected to get much hotter and probably emit X-rays.

Adapted from information issued by the Max Planck Institute for Extraterrestrial Physics.

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Rogue stars sail in intergalactic space

Animation of a rogue star

Illustration of a rogue star being ejected from the galaxy after tangling with the Milky Way’s central black hole.

IT’S VERY DIFFICULT to knock a star out of our Milky Way galaxy. In fact, the main mechanism that astronomers have come up with that can give a star the three-million-plus kilometre-per-hour kick it takes involves tangling with the supermassive black hole at the Milky Way’s core.

So far astronomers have found 16 of these “hypervelocity” stars. Although they are travelling fast enough to eventually escape galaxy’s gravitational grasp, they have actually been discovered while they are still inside the galaxy.

Now, astronomers report in a recent issue of the Astronomical Journal that they’ve identified a group of more than 675 stars on the outskirts of the Milky Way, which they argue are hypervelocity stars that have been ejected from the galactic core.

They selected these stars based on their location in intergalactic space between the Milky Way and the nearby Andromeda galaxy and by their peculiar red coloration.

“These stars really stand out. They are red giant stars with high metallicity which gives them an unusual colour,” says Vanderbilt University Assistant Professor Kelly Holley-Bockelmann who conducted the study with graduate student Lauren Palladino.

In astronomy and cosmology, “metallicity” is a measure of the proportion of chemical elements other than hydrogen and helium that a star contains. In this case, high metallicity is a signature that indicates an inner galactic origin—older stars and stars from the galactic fringes tend to have lower metallicities.

The researchers identified the candidates by analysing millions of stars catalogued in the Sloan Digital Sky Survey.

Illustration of a supermassive black hole

Illustration of a supermassive black hole, like the one thought to reside at the core of our Milky Way galaxy.

Encounter with a black hole

“We figured that these rogue stars must be there, outside the galaxy, but no one had ever looked for them. So we decided to give it a try,” said Holley-Bockelmann, who is studying the behaviour of the black hole at the centre of the Milky Way galaxy.

Astronomers have now found evidence for giant black holes at the centres of many galaxies. They estimate that the Milky Way’s central black hole has a mass of four million solar masses. They calculate that the gravitational field surrounding such a supermassive black hole is strong enough to accelerate stars to hypervelocities.

The typical scenario involves a binary pair of stars that get caught in the black hole’s grip. As one of the stars spirals in towards the black hole, its companion is flung outward at a tremendous velocity. A second scenario takes place during periods when the central black hole is in the process of ingesting a smaller black hole. Any star that ventures too close to the circling pair can also get a hypervelocity kick.

Even travelling at hypervelocities, it would take a star about 10 million years to travel from the Milky Way’s central hub to its outskirts 50,000 light years away.

Adapted from information issued by Vanderbilt University. Images courtesy Michael Smelzer / Vanderbilt University / Jenni Ohnstad / NASA Jet Propulsion Laboratory.

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Video: Mystery X-ray source in distant galaxy

SINCE THE 1980s, astronomers have known about a mysterious class of objects that they call “ultraluminous X-ray sources,” or ULXs. They named them this because these objects give off more X-rays than most other binary star systems where black holes or neutron stars are in orbit around a normal companion star.

Recently, scientists using NASA’s Chandra X-ray Observatory and optical telescopes spotted a ULX in the spiral galaxy M83 that was acting even more strangely. This ULX increased its output in X-rays by 3,000 times over the course of several years.

Using clues found in the X-ray and optical data, researchers think this ULX may be a member of a population of black holes that up until now was suspected to exist but had not been confirmed.

These black holes, which are the smaller stellar-mass black holes (ones that form from the collapse of a giant star), are older and more active than previously thought.

Video courtesy NASA / CXC. Image close-ups – X-ray, NASA / CXC / Curtin University / R. Soria et al.; optical, NASA / STScI / Middlebury College / F. Winkler et al.

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Galaxy caught blowing bubbles

Hubble Space Telescope image of Holmberg II

The Hubble Space Telescope captured this image of dwarf irregular galaxy Holmberg II. The main part of the galaxy is the spread of stars in the lower left half of the image. Huge bubbles of glowing gas produced by stellar explosions dominate the galaxy; they are now sites of ongoing star formation.

HUBBLE’S FAMOUS IMAGES OF GALAXIES typically show them to be elegant spirals or soft-edged elliptical shapes.

But these neat forms are only representative of large galaxies. Smaller galaxies like the dwarf irregular galaxy Holmberg II come in many shapes and types that are harder to classify.

Holmberg II’s indistinct shape is punctuated by huge glowing bubbles of gas, captured in this image from the Hubble Space Telescope.

The intricate glowing shells of gas were formed by the energetic life cycles of many generations of stars. High-mass stars form in dense regions of gas, and later in life expel strong stellar winds that blow away the surrounding material.

At the very end of their lives, they explode in as a supernova. Shock waves rip through these less dense regions blowing out and heating the gas, forming the delicate shells we see today.

Holmberg II is a patchwork of dense star-forming regionsand extensive barren areas with less material, which can stretch across thousands of light-years.

Keck Observatory view of Holmberg II

A wider view of Holmberg II. Courtesy B. Mendez / Keck Observatory.

As a dwarf galaxy, it has neither the spiral arms typical of galaxies like the Milky Way nor the dense nucleus of an elliptical galaxy.

This makes Holmberg II, gravitationally speaking, a gentle haven where fragile structures such as these bubbles can hold their shape.

A hidden black hole?

While the galaxy is unremarkable in size, Holmberg II does have some intriguing features. As well as its unusual appearance—which earned it a place in Halton Arp’s Atlas of Peculiar Galaxies, a treasure trove of weird and wonderful objects—the galaxy hosts an ultraluminous X-ray source in the middle of the three gas bubbles in the top right of the image.

There are competing ideas as to what causes this powerful radiation—one intriguing possibility is that an intermediate-mass black hole is pulling in material from its surroundings, with the material giving off energy as it nears the black hole.

The colourful image is a composite of visible and near-infrared exposures taken using the Wide Field Channel of Hubble’s Advanced Camera for Surveys. Hubble is a project of international cooperation between the European Space Agency and NASA.

Download the Hubble wallpapers:

Holmberg II (1024×768, 588.2 KB)

Holmberg II (1280×1024, 1.0 MB)

Holmberg II (1600×1200, 1.5 MB)

Holmberg II (1920×1200, 1.8 MB)

Adapted from information issued by HEIC / NASA / ESA.

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Beyond Einstein — the video

ALBERT EINSTEIN’S THEORIES rank among humanity’s greatest achievements, and sparked the scientific revolution of the 20th Century.

In their attempts to understand how space, time and matter are connected, Einstein and his successors made three predictions:

First, that space is expanding from a Big Bang.

Second, that black holes exist—these extremely dense places in the universe where space and time are tied into contorted knots and where time itself stops.

And third, that there is some kind of energy pulling the universe apart.

These three predictions seemed so far-fetched, that everyone, including Einstein himself, thought they were unlikely.

Yet incredibly, all three have turned out to be true.

This is where NASA’s Beyond Einstein programme begins. Using advanced space-based technology to explore these three questions, NASA and its partners begin the next revolution in our understanding of the universe.

NASA’s Beyond Einstein programme is poised to complete Einstein’s legacy—and ultimately unravel the mysteries of the Universe.

Adapted from information issued by NASA / Goddard Space Flight Centre.

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Milestone as radio dishes linked

ASKAP antennae

Antennae of CSIRO's Australian SKA Pathfinder (ASKAP) telescope in Western Australia were linked with other dishes across Australasia to provide incredible detail of a distant quasar. Photo: Terrace Photographers

THE DISCOVERY POTENTIAL of the future international Square Kilometre Array (SKA) radio telescope has been glimpsed following the commissioning of a working optical fibre link between CSIRO’s Australian SKA Pathfinder (ASKAP) telescope in Western Australia, and other radio telescopes across Australia and New Zealand.

The achievement will be announced at the 2011 International SKA Forum, taking place this week in Banff, Canada.

On 29 June, six telescopes—ASKAP, three CSIRO telescopes in New South Wales, a University of Tasmania telescope and another operated by the Auckland University of Technology—were used together to observe a radio source that may be two black holes orbiting each other.

Data from all sites were streamed in real time to Curtin University in Perth  (a node of the International Centre for Radio Astronomy Research) and there processed to make an image.

This ability to successfully link antennae (dishes) over large distances will be vital for the future $2.5 billion SKA telescope, which will have several thousand antennae, up to 5,500 kilometres apart, working together as a single telescope. Linking antennae in such a manner allows astronomers to see distant galaxies in more detail.

Map of antennae across Australia and New Zealand

The network of radio telescope dishes stretched across Australia and New Zealand. Image: Carl Davies, CSIRO

“We now have an SKA-scale network in Australia and New Zealand: a combination of CSIRO and NBN-supported fibre and the existing AARNET and KAREN research and education networks,” said SKA Director for Australasia, Dr Brian Boyle.

Watching as black holes feed

The radio source the astronomers targeted was PKS 0637-752, a quasar that lies more than seven and a half billion light-years away from us.

This quasar emits a spectacular radio jet with regularly spaced bright spots in it, like a string of pearls. Some astronomers have suggested that this striking pattern is created by two black holes in orbit around each other, one black hole periodically triggering the other to ‘feed’ and emit a burst of radiation.

Radio image of a quasar

The radio dish network was used to zoom in on quasar PKS0637-752, at the heart of which is thought to be two black holes circling each other. ATCA image: L. Godfrey (Curtin Uni.) and J. Lovell (Uni. of Tasmania). Image from telescope network: S. Tingay (Curtin Uni.) et al.

‘It’s a fascinating object, and we were able to zoom right into its core, seeing details just a few millionths of a degree in scale, equivalent to looking at a 10-cent piece from a distance of 1,000 kilometres,’ said CSIRO astronomer Dr Tasso Tzioumis.

During the experiment Dr Tzioumis and fellow CSIRO astronomer Dr Chris Phillips controlled all the telescopes over the Internet from Sydney.

Curtin University’s Professor Steven Tingay and his research team built the system used to process the telescope data. “Handling the terabytes of data that will stream from ASKAP is within reach, and we are on the path to the SKA,” he said.

“For an SKA built in Australia and New Zealand, this technology will help connect the SKA to major radio telescopes in China, Japan, India and Korea.”

AARNet, which provides the data network for Australia’s research institutions, has recently shown that it can implement data rates of up to 40 Gbps on existing fibre networks. That figure is for a single wavelength, and one fibre can support up to 80 wavelengths.

Adapated from information issued by CSIRO Astronomy and Space Science.

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