Journal articles: 'Australian Space Telescopes'

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Tuohy, Ian R. "Space Telescopes: an International Perspective." Publications of the Astronomical Society of Australia 8, no. 1 (1989): 2–24. http://dx.doi.org/10.1017/s1323358000022827.

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AbstractThe purpose of this paper is to review current and planned Space Astronomy missions from an international perspective, with principal attention to the programs of the USA, Europe, Japan and the USSR. The review focusses on extra-solar astrophysics, and the capabilities and broad research objectives of numerous individual spacecraft are described. These collectively span more than seventeen decades in wavelength and thus provide an essential complement to ground-based astronomy. Many of the missions offer significant opportunities for Australian participation via three complementary routes. First through Guest Investigator programs analogous to that offered for the Hubble Space Telescope (HST). Second, through the proposed establishment of an Australian Space Astronomy Data Centre to gain access to archival data from HST and other missions (the creation of such an archival facility in Canada is highlighted as a pertinent example). Third, via the contribution of instrumentation or ground support services. This latter category includes the Radioastron VLBI mission for which an agreement with the USSR has already been signed. In addition, an unprecedented opportunity has arisen for Australia to provide a ground station for the Infrared Space Observatory (ISO), due to be launched by ESA in 1993. In return for providing this service, the Australian astronomical community would receive a guaranteed share of the ISO observing time during the two year mission. Finally, Australian astronomers have been invited to contribute an advanced All-sky X-ray Monitor for the Soviet Spectrum-X-Gamma mission in 1993. This opportunity, and also the Radioastron initiative, have arisen under the USSR-Australia Space Research Agreement signed in December 1987.

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Bhathal, R. "Campbelltown Rotary Observatory." Publications of the Astronomical Society of Australia 17, no. 2 (2000): 176–78. http://dx.doi.org/10.1071/as00176.

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AbstractDonations (in cash and kind) amounting to $200,000 from companies in the south-western Sydney region have allowed the construction of a teaching, research and public access Observatory at the University of Western Sydney in Campbelltown. The Observatory will also serve as the home of the Australian Optical SETI Project (OZ OSETI for short). Two fibre-glass domes will be installed at the site. The main 4.5 m fibre-glass dome will house a 0.4 m telescope while the smaller 2.9 m dome will house a 0.3 m telescope. Both telescopes are fork-mounted Schmidt-Cassegrains working at f/10. An outside observation area will be used for tripod-mounted telescopes for public use and teaching purposes. The expected completion date for the project is July 2000.

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Bains, I., S. L. Breen, M. G. Burton, M. R. Cunningham, P. A. Jones, A. Kawamura, N. Lo, G. P. Rowell, and A. Walsh. "Recent Science from Australian Large-Scale Millimetre Mapping Projects: Proceedings from a Swinburne University Workshop." Publications of the Astronomical Society of Australia 26, no. 2 (2009): 110–20. http://dx.doi.org/10.1071/as08027.

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AbstractSince the recent upgrades to the Australia Telescope National Facility (ATNF) Mopra telescope back-end and receiver system, it has risen from an under-subscribed facility to a sought-after instrument with heavy international competition to gain time. Furthermore, the introduction of the on-the-fly mapping capability in 2004 has made this technique one of Mopra's most popular observing modes. In addition, the recent upgrade of the NANTEN millimetre-wavelength telescope to the sub-millimetre NANTEN2 instrument, has provided a complementary, higher-frequency facility to Mopra. A two-day workshop was held at Swinburne University in June 2008 to disseminate the current state of ongoing large-scale mapping projects and associated spin-offs that the telescopes' upgrades have facilitated, and to decide upon future research directions. Here, we provide a summary of the result-oriented talks as a record of the state of Australian-access single-dish millimetre science in 2008.

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Bland-Hawthorn, J., and L. Kedziora-Chudczer. "Taurus Tunable Filter — Seven Years of Observing." Publications of the Astronomical Society of Australia 20, no. 3 (2003): 242–51. http://dx.doi.org/10.1071/as02023.

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AbstractThe Taurus Tunable Filter (TTF) has now been in regular use for seven years on the Anglo–Australian Telescope (AAT). The instrument was also used for three years (1996–1999) on the William Herschel Telescope (WHT). We present a brief review of the different applications in order to illustrate the versatility of tunable filters in optical/IR spectrophotometric imaging. Tunable filters are now either planned or under development for 6–10 m class telescopes which ensures their use for years to come.

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Jones, P. A. "The Structure and Size of Radio Galaxy 1308-441." Publications of the Astronomical Society of Australia 7, no. 2 (1987): 208–11. http://dx.doi.org/10.1017/s1323358000022220.

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AbstractThe structure of the radio source 1308-441 has been determined with the Molonglo and Fleurs radio telescopes. The nuclear component has been identified with a magnitude 15 galaxy and an optical spectrum, obtained with the Anglo-Australian Telescope shows galactic absorption features with a redshift of 0.0515 but no emission lines. The radio image shows the nuclear component linked by a well defined bridge to diffuse lobes extending for 11 arcmin west and 6 arcmin east. The asymmetry is believed to be due to projection effects. The projected size is 670 kpc (Ho = 100 km s-1 Mpc-1). The bridge contains several peaks with one strong unresolved peak 90 kpc from the galaxy.

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Dodson, Richard, Dion Lewis, David Legge, Peter McCulloch, John Reynolds, David McConnell, and Avinash Deshpande. "The Vela Pulsar, the Key?" Symposium - International Astronomical Union 218 (2004): 193–94. http://dx.doi.org/10.1017/s0074180900180945.

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Of all pulsars known, Vela has been one of the most productive in terms in understanding pulsars and their characteristics. We present the latest results derived from Australian telescopes. These include a more accurate pulsar distance, a more precise pulsar local space velocity, a new model of spin-up at a glitch, and the association of a radio nebula with the X-ray pulsar wind nebula.

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Robertson, J. G. "MAPPIT 2: Second Generation High-resolution Imaging at the AAT." Publications of the Astronomical Society of Australia 14, no. 2 (1997): 189–94. http://dx.doi.org/10.1071/as97189.

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AbstractInterferometric methods have been used at a number of observatories to improve the spatial resolution of large optical telescopes, approaching and in some cases reaching the diffraction limit. The principal methods used have been speckle interferometry and non-redundant masking (NRM). The MAPPIT (Masked APerture Plane Interference Telescope) instrument has been used for NRM observations at the 3·9 m Anglo-Australian Telescope. This paper describes a proposed instrument, MAPPIT 2, which would use a Shack-Hartmann wavefront sensor in parallel with an interferometer performing NRM or one-dimensional speckle interferometry. The inclusion of the data from the wavefront sensor will enhance the sensitivity of the instrument, especially for the imaging of relatively complex objects (those giving more than a few resolution elements with non-zero intensities). Limiting the instantaneous spatial resolution to one dimension allows available CCD detectors to operate with 100% duty cycle. Observations at a number of position angles allow two-dimensional images to be obtained.

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Uno, Y., H. Imai, K. Shinano, H.-H. Qiao, J. R. Dawson, S. L. Breen, and J. F. Gómez. "Modelled 3D distribution of OH/IR stars in the Galactic disc." Monthly Notices of the Royal Astronomical Society 502, no. 2 (January 22, 2021): 3012–20. http://dx.doi.org/10.1093/mnras/stab176.

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ABSTRACT We have modelled the 3D distribution of OH/IR stars in the Galactic plane, traced by 1612 MHz OH maser sources with classic double horned spectral profiles. We statistically analysed over 700 maser sources detected by the HI/OH/Recombination line survey of the Milky Way (THOR) and the Australia Telescope Compact Array interferometric follow-up observations of the Southern Parkes Large-Area Survey in Hydroxyl (SPLASH). With a simple model constructed from a classical density distribution of stars and luminosity functions of OH maser sources in the Galaxy, we estimate the scale height, or the half thickness of the OH/IR star distribution along the Galactic disc to be 90–290 pc. The simple model also implies that there are ∼4000 OH/IR stars hosting 1612 MHz OH masers along the Galactic Plane. Therefore, next generation telescopes such as the Australian Square Kilometre Array Pathfinder (ASKAP) and SKA Phase 1 will detect about 80 per cent of such OH/IR stars in the Galaxy at a 10 mJy detection limit. Comparing the data of previously detected circumstellar 1612 MHz OH maser sources with those of THOR and SPLASH, the maser source lifetime is estimated to be ∼300 yr. This is likely a lower limit, since non-detections of masers in some cases could be affected by the flux variation of the maser source.

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Burton, Michael, D. K. Aitken, D. A. Allen, M. C. B. Ashley, M. G. Burton, R. D. Cannon, B. D. Carter, et al. "The Scientific Potential for Astronomy from the Antarctic Plateau: A Report prepared by the Australian Working Group for Antarctic Astronomy." Publications of the Astronomical Society of Australia 11, no. 2 (August 1994): 127–50. http://dx.doi.org/10.1017/s1323358000019809.

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Our knowledge of the universe comes from recording the photon and particle fluxes incident on the Earth from space. We thus require sensitive measurement across the entire energy spectrum, using large telescopes with efficient instrumentation located on superb sites. Technological advances and engineering constraints are nearing the point where we are recording as many photons arriving at a site as is possible. Major advances in the future will come from improving the quality of the site. The ultimate site is, of course, beyond the Earth’s atmosphere, such as on the Moon, but economic limitations prevent our exploiting this avenue to the degree that the scientific community desires. Here we describe an alternative, which offers many of the advantages of space for a fraction of the cost: the Antarctic Plateau.

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Agarwal, Devansh, Duncan R. Lorimer, Anastasia Fialkov, Keith W. Bannister, Ryan M. Shannon, Wael Farah, Shivani Bhandari, et al. "A fast radio burst in the direction of the Virgo Cluster." Monthly Notices of the Royal Astronomical Society 490, no. 1 (September 16, 2019): 1–8. http://dx.doi.org/10.1093/mnras/stz2574.

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ABSTRACT The rate of fast radio bursts (FRBs) in the direction of nearby galaxy clusters is expected to be higher than the mean cosmological rate if intrinsically faint FRBs are numerous. In this paper, we describe a targeted search for faint FRBs near the core of the Virgo Cluster using the Australian Square Kilometre Array Pathfinder telescope. During 300 h of observations, we discovered one burst, FRB 180417, with dispersion measure (DM) = 474.8 cm−3 pc. The FRB was promptly followed up by several radio telescopes for 27 h, but no repeat bursts were detected. An optical follow-up of FRB 180417 using the PROMPT5 telescope revealed no new sources down to an R-band magnitude of 20.1. We argue that FRB 180417 is likely behind the Virgo Cluster as the Galactic and intracluster DM contribution are small compared to the DM of the FRB, and there are no galaxies in the line of sight. The non-detection of FRBs from Virgo constrains the faint-end slope, α < 1.52 (at 68 per cent confidence limit), and the minimum luminosity, Lmin ≳ 2 × 1040 erg s−1 (at 68 per cent confidence limit), of the FRB luminosity function assuming cosmic FRB rate of 104 FRBs per sky per day with flux above 1 Jy located out to redshift of 1. Further FRB surveys of galaxy clusters with high-sensitivity instruments will tighten the constraints on the faint end of the luminosity function and, thus, are strongly encouraged.

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Chauhan, J., J. C. A. Miller-Jones, G. E. Anderson, W. Raja, A. Bahramian, A. Hotan, B. Indermuehle, et al. "An H i absorption distance to the black hole candidate X-ray binary MAXI J1535–571." Monthly Notices of the Royal Astronomical Society: Letters 488, no. 1 (July 15, 2019): L129—L133. http://dx.doi.org/10.1093/mnrasl/slz113.

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ABSTRACT With the Australian Square Kilometre Array Pathfinder (ASKAP) we monitored the black hole candidate X-ray binary MAXI J1535–571 over seven epochs from 2017 September 21 to October 2. Using ASKAP observations, we studied the H i absorption spectrum from gas clouds along the line of sight and thereby constrained the distance to the source. The maximum negative radial velocities measured from the H i absorption spectra for MAXI J1535–571 and an extragalactic source in the same field of view are −69 ± 4 and −89 ± 4 km s−1, respectively. This rules out the far kinematic distance ($9.3^{+0.5}_{-0.6}$ kpc), giving a most likely distance of $4.1^{+0.6}_{-0.5}$ kpc, with a strong upper limit of the tangent point at $6.7^{+0.1}_{-0.2}$ kpc. At our preferred distance, the peak unabsorbed luminosity of MAXI J1535–571 was >78 per cent of the Eddington luminosity, and shows that the soft-to-hard spectral state transition occurred at the very low luminosity of (1.2–3.4) × 10−5 times the Eddington luminosity. Finally, this study highlights the capabilities of new wide-field radio telescopes to probe Galactic transient outbursts, by allowing us to observe both a target source and a background comparison source in a single telescope pointing.

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Steel, Duncan. "Asteroid Discovery Efficiencies for Telescope Systems at Siding Spring." Publications of the Astronomical Society of Australia 12, no. 2 (August 1995): 202–14. http://dx.doi.org/10.1017/s1323358000020282.

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AbstractRelative efficiencies for the discovery of Earth-crossing asteroids (ECAs) are modelled for various telescopes at Siding Spring. It is found that the narrow-field instruments—the Anglo-Australian Telescope and the 40 in and 2·3m reflectors—are not competitive in this regard for present CCD imaging systems. The UK Schmidt Telescope (UKST), if used to take short-exposure stereo pairs of photographs, would be an effective search tool, outperforming all current systems apart from the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) systems now being implemented by the US Air Force for ECA searches. If a CCD mosaic were fitted to the UKST, its performance would far exceed that of any other device at Siding Spring, and it would produce ECA discoveries at a rate around 3–4 times as high as GEODSS, but at considerable expense. The most sophisticated search instrument currently in use is the University of Arizona’s Spacewatch telescope; a notable result found here is that even with its present CCD, the Automated Patrol Telescope (APT) of the University of New South Wales would be able to match or outperform Spacewatch for all ECA sizes, including ~10m objects, should this modelling be a reasonable representation of its real performance. In terms of cost-effectiveness and telescope availability, the conclusion arrived at herein is that the APT, equipped with small-pixel but large-format CCD chips of high quantum efficiency, would be an extremely effective ECA search instrument: if operated with 12 μm pixel chips covering a 4° × 4° field it might produce ECA discoveries at a rate well in excess of the combined rate for all current search programs.

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Bland-Hawthorn, Joss, and D. Heath Jones. "Taurus Tunable Filter: A Flexible Approach to Narrowband Imaging." Publications of the Astronomical Society of Australia 15, no. 1 (1998): 44–49. http://dx.doi.org/10.1071/as98044.

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AbstractThe Taurus Tunable Filter (TTF) is a tunable narrowband interference filter covering wavelengths from 6300 Å to the sensitivity drop-off of conventional CCDs (∼9600 Å), although a blue ‘arm’ (4000–6500 Å) is to be added by the end of 1997. The TTF offers monochromatic imaging at the Cassegrain foci of both the Anglo-Australian and William Herschel Telescopes, with an adjustable passband of between 6 and 60 Å. In addition, frequency switching with the TTF can be synchronised with movement of charge (charge shuffling) on the CCD, which has important applications to many astrophysical problems. Here we review the different modes of TTF and suggest their use for follow-up narrowband imaging to the AAO/UKST Galactic Plane Hα Survey.

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Orchiston, Wayne. "From the Solar Corona to Clusters of Galaxies: The Radio Astronomy of Bruce Slee." Publications of the Astronomical Society of Australia 21, no. 1 (2004): 23–71. http://dx.doi.org/10.1071/as03009.

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AbstractOwen Bruce Slee is one of the pioneers of Australian radio astronomy. During World War II he independently discovered solar radio emission, and, after joining the CSIRO Division of Radiophysics, used a succession of increasingly more sophisticated radio telescopes to examine an amazing variety of celestial objects and phenomena. These ranged from the solar corona and other targets in our solar system, to different types of stars and the ISM in our Galaxy, and beyond to distant galaxies and clusters of galaxies. Although long retired, Slee continues to carry out research, with emphasis on active stars and clusters of galaxies. A quiet and unassuming man, Slee has spent more than half a century making an important, wide-ranging contribution to astronomy, and his work deserves to be more widely known.

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Hollow, R. P. "The Student as Scientist: Secondary Student Research Projects in Astronomy." Publications of the Astronomical Society of Australia 17, no. 2 (2000): 162–67. http://dx.doi.org/10.1071/as00162.

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AbstractStudent research projects are becoming either integral or optional components of Science curricula in several countries. They provide a valuable opportunity for high school students to experience many of the joys and frustrations that make up the intellectual challenge of Science. Astronomy is one branch of Science that lends itself to student projects. Student Research Projects (SRPs) can be individual, group or collaborative between groups in other schools or countries and may involve professional mentors. Use of the Internet and remote access telescopes allow students to undertake challenging research and make worthwhile contributions to professional programs. This paper presents case studies of student projects in optical and radio astronomy from Australian and overseas schools and details both the benefits and problems faced in conducting such projects. Student responses to involvement in projects are discussed. Potential areas for future collaboration and development are highlighted together with the need for more research as to the most effective ways to implement projects and develop student skills.

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Mahony, Elizabeth K., James R. Allison, Elaine M. Sadler, Sara L. Ellison, Sui Ann Mao, Raffaella Morganti, Vanessa A. Moss, et al. "H i absorption at z ∼ 0.7 against the lobe of the powerful radio galaxy PKS 0409−75." Monthly Notices of the Royal Astronomical Society 509, no. 2 (October 25, 2021): 1690–702. http://dx.doi.org/10.1093/mnras/stab3041.

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ABSTRACT We present results from a search for the H i 21-cm line in absorption towards 16 bright radio sources with the six-antenna commissioning array of the Australian Square Kilometre Array Pathfinder. Our targets were selected from the 2-Jy sample, a flux-limited survey of the southern radio sky with extensive multiwavelength follow-up. Two sources were detected in H i absorption including a new detection towards the bright Fanaroff–Riley Type II radio galaxy PKS 0409−75 at a redshift of $z$ = 0.674. The H i absorption line is blueshifted by ∼3300 km s−1 compared to the optical redshift of the host galaxy of PKS 0409−75 at $z$ = 0.693. Deep optical imaging and spectroscopic follow-up with the GMOS instrument on the Gemini-South telescope reveal that the H i absorption is associated with a galaxy in front of the southern radio lobe with a stellar mass of 3.2–6.8 × 1011 M⊙, a star formation rate of ∼1.24 M⊙ yr−1, and an estimated H i column density of 2.16 × 1021 cm−2, assuming a spin temperature of Tspin = 500 K and source covering factor of Cf = 0.3. Using polarization measurements of PKS 0409−75 from the literature, we estimate the magnetic field of the absorbing galaxy to be ∼14.5 $\mu$G, consistent with field strengths observed in nearby spiral galaxies but larger than expected for an elliptical galaxy. Results from this pilot study can inform future surveys as new wide-field telescopes allow us to search for 21-cm H i absorption towards all bright radio sources as opposed to smaller targeted samples.

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Allison, James R. "A statistical measurement of the H i spin temperature in DLAs at cosmological distances." Monthly Notices of the Royal Astronomical Society 503, no. 1 (February 24, 2021): 985–96. http://dx.doi.org/10.1093/mnras/stab518.

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ABSTRACT Evolution of the cosmic star formation rate (SFR) and molecular gas mass density is expected to be matched by a similarly strong evolution of the fraction of atomic hydrogen (H i) in the cold neutral medium (CNM). We use results from a recent commissioning survey for intervening 21-cm absorbers with the Australian Square Kilometre Array Pathfinder (ASKAP) to construct a Bayesian statistical model of the NH i-weighted harmonic mean spin temperature (Ts) at redshifts between z = 0.37 and 1.0. We find that Ts ≤ 274 K with 95 per cent probability, suggesting that at these redshifts the typical H i gas in galaxies at equivalent DLA column densities may be colder than the Milky Way interstellar medium (Ts, MW ∼ 300 K). This result is consistent with an evolving CNM fraction that mirrors the molecular gas towards the SFR peak at z ∼ 2. We expect that future surveys for H i 21-cm absorption with the current SKA pathfinder telescopes will provide constraints on the CNM fraction that are an order of magnitude greater than presented here.

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Murphy, Tara, Peter Lamb, Christopher Owen, and Malte Marquarding. "Data Storage, Processing, and Visualization for the Australia Telescope Compact Array." Publications of the Astronomical Society of Australia 23, no. 1 (2006): 25–32. http://dx.doi.org/10.1071/as05033.

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AbstractWe present three Virtual Observatory tools developed at the Australia Telescope National Facility (ATNF) for the storage, processing and visualization of Australia Telescope Compact Array (ATCA) data. These are the Australia Telescope Online Archive, a prototype data-reduction pipeline, and the Remote Visualization System. These tools were developed in the context of the Virtual Observatory and were intended to be both useful for astronomers and technology demonstrators. We discuss the design and implementation of these tools, as well as issues that should be considered when developing similar systems for future telescopes.

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Moore, J. A., B. Gendre, D. M. Coward, H. Crisp, and A. Klotz. "THE ZADKO OBSERVATORY." Revista Mexicana de Astronomía y Astrofísica Serie de Conferencias 53 (September 1, 2021): 35–39. http://dx.doi.org/10.22201/ia.14052059p.2021.53.08.

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The 1.0 metre f/4 fast-slew Zadko Telescope was installed in June 2008 approximately seventy kilometres north of Perth at Yeal, in the Shire of Gingin, Western Australia. Since the Zadko Telescope has been in operation it has proven its worth by detecting numerous Gamma Ray Burst afterglows, two of these being the most distant 'optical transients' imaged by an Australian telescope. Other projects include a contract with the European Space Agency (ESA) to image potentially hazardous near Earth asteroids (2019), monitoring space weather on nearby stars (2019), and photometry of a transit of Saturn's moon Titan (2018). Another active Zadko Telescope project is tracking Geostationary satellites and attempting to use photometry to classify various space debris (defunct satellites). The Zadko Telescope's importance as a potential tool for education, training, and public outreach cannot be underestimated, as the global awareness of the importance of astronomy (and space science) as a context for teaching science continues to increase. An example of this was the national media coverage of its contribution to the discovery of colliding neutron stars in 2017, capturing the imagination of the public. In this proceeding, I will focus on the practical aspects of managing a robotic Observatory, focusing on the sustainability of the Observatory and the technical management involved in hosting different commercial projects. I will review the evolution of the Observatory, from its early, single instrument, state to its current multi-telescope and multi-instrument capabilities. I will finish by outlining the future of the Observatory and the site.

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Wang, Yuanming, Tara Murphy, David L. Kaplan, Teresa Klinner-Teo, Alessandro Ridolfi, Matthew Bailes, Fronefield Crawford, et al. "Discovery of PSR J0523-7125 as a Circularly Polarized Variable Radio Source in the Large Magellanic Cloud." Astrophysical Journal 930, no. 1 (May 1, 2022): 38. http://dx.doi.org/10.3847/1538-4357/ac61dc.

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Abstract We report the discovery of a highly circularly polarized, variable, steep-spectrum pulsar in the Australian Square Kilometre Array Pathfinder (ASKAP) Variables and Slow Transients (VAST) survey. The pulsar is located about 1° from the center of the Large Magellanic Cloud, and has a significant fractional circular polarization of ∼20%. We discovered pulsations with a period of 322.5 ms, dispersion measure (DM) of 157.5 pc cm−3, and rotation measure (RM) of +456 rad m−2 using observations from the MeerKAT and the Parkes telescopes. This DM firmly places the source, PSR J0523−7125, in the Large Magellanic Cloud (LMC). This RM is extreme compared to other pulsars in the LMC (more than twice that of the largest previously reported one). The average flux density of ∼1 mJy at 1400 MHz and ∼25 mJy at 400 MHz places it among the most luminous radio pulsars known. It likely evaded previous discovery because of its very steep radio spectrum (spectral index α ≈ −3, where S ν ∝ ν α ) and broad pulse profile (duty cycle ≳35%). We discuss implications for searches for unusual radio sources in continuum images, as well as extragalactic pulsars in the Magellanic Clouds and beyond. Our result highlighted the possibility of identifying pulsars, especially extreme pulsars, from radio continuum images. Future large-scale radio surveys will give us an unprecedented opportunity to discover more pulsars and potentially the most distant pulsars beyond the Magellanic Clouds.

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Tuohy, Ian R. "A Proposal for an Australian Space Astronomy Data Centre." Publications of the Astronomical Society of Australia 7, no. 1 (1987): 80–87. http://dx.doi.org/10.1017/s1323358000021901.

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AbstractThe concept of a national centre for the analysis of archival and contemporary space astronomy data has been identified as a highly desirable objective by the Australian astronomical community for a number of years. With the approaching launch of the Hubble Space Telescope (HST), the time is now appropriate to actively pursue this objective. HST will generate a data archive of unique astrophysical significance over the course of the ≥ 20 year mission. It is essential that Australian astronomers have efficient access to this resource, both to maintain our position at the forefront of astronomical research, and to complement our major ground-based facilities (particularly the AAT and the Australia Telescope). An Australian facility would provide efficient access to HST data and also to the analysis tools and expertise necessary for utilizing the data. Archival data from other NASA and ESA missions could also be supported, and in the longer term, the facility could become the science centre for the Lyman/Quasat missions.This paper presents the case for an Australian Space Astronomy Data Centre, reviews the astronomy missions of relevance, and addresses the role, scope and implementation timescale of the facility. Preliminary estimates are given for the resources that will be required, and possible routes for funding the centre are outlined. Above all, the report is intended as a Discussion Paper to promote further consideration of the concept and of the service that could be provided to the Australian astronomical community.

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Whiteoak, J. B. "The Australia Telescope Project: Going Along Nicely, Thank You!" Publications of the Astronomical Society of Australia 6, no. 3 (1986): 290–97. http://dx.doi.org/10.1017/s1323358000026874.

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AbstractAbstract: The Australia Telescope is an advanced radio astronomy facility planned to satisfy the major research requirements of Australian scientists. The construction project, begun in 1983, is now well along the way to completion as an Australian Bicentennial activity. The civil works at the main Culgoora site are complete. The construction of the seven 22-m antennas has begun: the first will be handed over in November 1986, the last a year later. Most other areas of the project – feed construction, receiver construction, computer development etc. are on schedule.

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Harnett, J. I., R. F. Haynes, R. Wielebinski, and U. Klein. "Radio Polarization Observations of Three Southern Galaxies." Publications of the Astronomical Society of Australia 8, no. 3 (1990): 257–60. http://dx.doi.org/10.1017/s1323358000023468.

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AbstractObservations of polarized emission and consequently the investigation of magnetic fields in northern galaxies, have been conducted successfully for some time with, for example, the 100-m Effelsberg telescope of the Max-Planck-Institut-für Radioastronomie and the VLA. However, the opportunity to make corresponding studies in the southern hemisphere has only recently become possible. Therefore, we have begun a long-range project aimed at studying the morphology and dynamics of southern galaxies using the facilities of the Parkes and Molonglo radio telescopes, the Siding Spring optical facilities and the Australia Telescope. Here we present preliminary results from Parkes observations of the three well known galaxies: NGC 253, NGC 4945 and M 83.

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Coward, D. M., M. Todd, T. P. Vaalsta, M. Laas-Bourez, A. Klotz, A. Imerito, L. Yan, et al. "The Zadko Telescope: A Southern Hemisphere Telescope for Optical Transient Searches, Multi-Messenger Astronomy and Education." Publications of the Astronomical Society of Australia 27, no. 3 (2010): 331–39. http://dx.doi.org/10.1071/as09078.

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AbstractThe new 1 m f/4 fast-slew Zadko Telescope was installed in June 2008 about 70 km north of Perth, Western Australia. It is the only metre-class optical facility at this southern latitude between the east coast of Australia and South Africa, and can rapidly image optical transients at a longitude not monitored by other similar facilities. We report on first imaging tests of a pilot program of minor planet searches, and Target of Opportunity observations triggered by the Swift satellite. In 12 months, 6 gamma-ray burst afterglows were detected, with estimated magnitudes; two of them, GRB 090205 (z = 4.65) and GRB 090516 (z = 4.11), are among the most distant optical transients imaged by an Australian telescope. Many asteroids were observed in a systematic 3-month search. In September 2009, an automatic telescope control system was installed, which will be used to link the facility to a global robotic telescope network; future targets will include fast optical transients triggered by high-energy satellites, radio transient detections, and LIGO gravitational wave candidate events. We also outline the importance of the facility as a potential tool for education, training, and public outreach.

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Robinson, B. J. "The Australian radio-telescope." Astrophysics and Space Science 118, no. 1-2 (January 1986): 57–61. http://dx.doi.org/10.1007/bf00651107.

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Bartos, I., K. R. Corley, N. Gupte, N. Ash, Z. Márka, and S. Márka. "Gravitational-wave follow-up with CTA after the detection of GRBs in the TeV energy domain." Monthly Notices of the Royal Astronomical Society 490, no. 3 (October 10, 2019): 3476–82. http://dx.doi.org/10.1093/mnras/stz2848.

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ABSTRACT The recent discovery of TeV emission from gamma-ray bursts (GRBs) by the MAGIC and H.E.S.S. Cherenkov telescopes confirmed that emission from these transients can extend to very high energies. The TeV energy domain reaches the most sensitive band of the Cherenkov Telescope Array (CTA). This newly anticipated, improved sensitivity will enhance the prospects of gravitational-wave follow-up observations by CTA to probe particle acceleration and high-energy emission from binary black hole and neutron star mergers, and stellar core-collapse events. Here we discuss the implications of TeV emission on the most promising strategies of choice for the gravitational-wave follow-up effort for CTA and Cherenkov telescopes more broadly. We find that TeV emission (i) may allow more than an hour of delay between the gravitational-wave event and the start of CTA observations; (ii) enables the use of CTA’s small size telescopes that have the largest field of view. We characterize the number of pointings needed to find a counterpart. (iii) We compute the annual follow-up time requirements and find that prioritization will be needed. (iv) Even a few telescopes could detect sufficiently nearby counterparts, raising the possibility of adding a handful of small-sized or medium-sized telescopes to the network at diverse geographic locations. (v) The continued operation of VERITAS/H.E.S.S./MAGIC would be a useful compliment to CTA’s follow-up capabilities by increasing the sky area that can be rapidly covered, especially in the United States and Australia, in which the present network of gravitational-wave detectors is more sensitive.

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Paron, Sergio A., Estela M. Reynoso, Cormac Purcell, Gloria M. Dubner, and Anne Green. "An Atomic and Molecular Study of the Interstellar Medium Around the Supernova Remnant RCW 103." Publications of the Astronomical Society of Australia 23, no. 2 (2006): 69–75. http://dx.doi.org/10.1071/as06003.

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AbstractWe report on the detection of HCO+ and 12CO emission in the rotational transition J = 1–0 in the vicinity of the shock front at the southern border of the supernova remnant RCW 103, where previous infrared observations suggest an interaction with a molecular cloud. The observations were carried out with the Australian Millimeter Radiotelescope at Mopra. We observed a depletion of HCO+ behind the supernova shock front. In addition, we studied the interstellar medium over an extended region towards RCW 103 based on archival λ 21 cm Hı line observations from the Australia Telescope Compact Array (ATCA) and the Parkes Telescope. No atomic gas was observed in emission in coincidence with the molecular feature. This absence was interpreted in terms of self-absorption processes.

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Drinkwater, Michael J., David G. Barnes, and Sara L. Ellison. "Using the COSMOS/UKST Southern Sky Object Catalogue." Publications of the Astronomical Society of Australia 12, no. 2 (August 1995): 248–57. http://dx.doi.org/10.1017/s1323358000020348.

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AbstractA complete copy of the compressed COSMOS/UKST Southern Sky Object Catalogue is now available on-line at the Anglo-Australian Observatory and the Australia Telescope National Facility. The catalogue lists image parameters for all objects detected to a limit of BJ ≈ 21·5 in the UK Schmidt Southern Sky Survey. We have written software to access the catalogue efficiently and generate finding charts or text listings of the image parameters. In this paper we describe the software and give some examples of its use. We also discuss the astrometric precision of the catalogue.

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Pearlman, Aaron B., Walid A. Majid, and Thomas A. Prince. "Observations of Radio Magnetars with the Deep Space Network." Advances in Astronomy 2019 (June 2, 2019): 1–12. http://dx.doi.org/10.1155/2019/6325183.

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The Deep Space Network (DSN) is a worldwide array of radio telescopes which supports NASA’s interplanetary spacecraft missions. When the DSN antennas are not communicating with spacecraft, they provide a valuable resource for performing observations of radio magnetars, searches for new pulsars at the Galactic Center, and additional pulsar-related studies. We describe the DSN’s capabilities for carrying out these types of observations. We also present results from observations of three radio magnetars, PSR J1745–2900, PSR J1622–4950, and XTE J1810–197, and the transitional magnetar candidate, PSR J1119–6127, using the DSN radio telescopes near Canberra, Australia.

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Swarup, Govind. "The Journey of a Radio Astronomer: Growth of Radio Astronomy in India." Annual Review of Astronomy and Astrophysics 59, no. 1 (September 8, 2021): 1–19. http://dx.doi.org/10.1146/annurev-astro-090120-014030.

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In this autobiographical account, I first describe my family, then childhood and education in India. During 1953–55, I worked in the new field of radio astronomy at the Division of Radiophysics of the Commonwealth Scientific and Industrial Research Organisation in Australia. During 1956–57, I worked at the Radio Astronomy Station of Harvard University at Fort Davis, Texas, where I made observations of solar radio bursts at decimeter wavelengths. I then joined Stanford University as a graduate student in 1957. I contributed to the successful operation of the Stanford Cross Antenna and then used it for studying microwave radio emission from the Sun. I was awarded the Ph.D. degree by Stanford University in 1960 and was then appointed as an Assistant Professor for three years. With an urge to contribute to evolving scientific endeavors in India, I joined the Tata Institute of Fundamental Research (TIFR) at Mumbai, India, in April 1963. In my stay of more than three decades at TIFR, I conceived of, and guided, construction of two of the world's largest radio telescopes, namely the Ooty Radio Telescope and the Giant Metrewave Radio Telescope. These instruments have led to several outstanding contributions and discoveries in the areas of radio galaxies, quasars, pulsars, and cosmology.

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Morton, Donald C. "Recent developments with the Anglo-Australian Telescope." Astrophysics and Space Science 118, no. 1-2 (January 1986): 31–33. http://dx.doi.org/10.1007/bf00651102.

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Kellermann, K. I. "VLBI in the 1990s." Publications of the Astronomical Society of Australia 8, no. 04 (1990): 327–29. http://dx.doi.org/10.1017/s1323358000023651.

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Abstract Radio telescopes in more than 20 different countries on five continents are being used for VLBI observations of galactic and extragalactic radio sources, as well for applications to geodesy and geophysics. New radio telescopes and networks of radio telescopes dedicated to VLBI which are being built in the United States, the U.S.S.R., Italy, China, Poland, the U.K. as well as in Australia will greatly improve the sensitivity, resolution, image quality, and frequency coverage of the existing networks. The Mk II VLBI recording system, which is based on consumer type Video Tape Recorders, is widely used but the sensitivity is limited. Broad band recording systems are expensive, but are becoming more popular due to their much greater sensitivity. They are expected to dominate VLBI systems in the 1990s. The first tests of an earth-to-space VLBI system took place in 1986, and by the mid 1990s dedicated VLBI antennas will be launched into earth orbit by the U.S.S.R. and by Japan in collaboration with Australia and other countries throughout the world. Space VLBI missions will give an order of magnitude improvement in resolution over the ground based VLBI networks operating at the same wavelengths.

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Caleb, M. "Fast Radio Bursts: from Multi-Beam Receivers to Interferometers." Proceedings of the International Astronomical Union 14, S339 (November 2017): 20. http://dx.doi.org/10.1017/s1743921318002119.

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AbstractRadio astronomy is currently exploring an intriguing new phase-space that probes the dynamic Universe on time-scales of milliseconds. Recent developments of sensitive, high-time-resolution instruments has made possible the discovery of millisecond-duration fast radio bursts (FRBs). The FRB class encompasses a number of single pulses, each unique in its own way, hindering a consensus for their origin. The key to de-mystifying FRBs lies in discovering many of them in real time in order to identify commonalities. The recently upgraded UTMOST, in Australia, has undergone a digital back-end transformation to rise as a fast-transient detection machine. The talk presented the first interferometric detections of FRBs made by this telescope at less that a quarter of its target sensitivity, placing their origin beyond the near-field region of the telescope and thus ruling out local sources of interference as a possible origin. Despite rigorous follow-ups, none of the FRBs observed with the upgraded UTMOST has been seen to repeat, suggesting the possibility of there being two independent classes of FRBs with two classes of possible progenitors. The talk then discussed the recent developments in the field, some of the open questions in FRB astronomy, and how the next-generation telescopes are vital in the quest to understand this enigmatic population.

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Angioni, R., E. Ros, M. Kadler, R. Ojha, C. Müller, P. G. Edwards, P. R. Burd, et al. "Gamma-ray emission in radio galaxies under the VLBI scope." Astronomy & Astrophysics 627 (July 2019): A148. http://dx.doi.org/10.1051/0004-6361/201935697.

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Aims. In the framework of the multi-wavelength and very long baseline interferometry (VLBI) monitoring program TANAMI (Tracking Active Nuclei with Austral Milliarcsecond Interferometry), we study the evolution of the parsec-scale radio emission in radio galaxies in the southern hemisphere and their relationship to the γ-ray properties of the sources. Our study investigates systematically, for the first time, the relationship between the two energy regimes in radio galaxies. In this first paper, we focus on Fermi-LAT-detected sources. Methods. The TANAMI program monitors a large sample of radio-loud AGN at 8.4 GHz and 22.3 GHz with the Australian long baseline array (LBA) and associated telescopes in Antarctica, Chile, New Zealand and South Africa. We performed a kinematic analysis for five γ-ray detected radio galaxies using multi-epoch 8.4 GHz VLBI images, deriving limits on intrinsic jet parameters such as speed and viewing angle. We analyzed 103 months of Fermi-LAT data in order to study possible connections between the γ-ray properties and the pc-scale jets of Fermi-LAT-detected radio galaxies, both in terms of variability and average properties. We discuss the individual source results and draw preliminary conclusions on sample properties including published VLBI results from the MOJAVE (Monitoring Of Jets in Active galactic nuclei with VLBA Experiments) survey, with a total of fifteen sources. Results. We find that the first γ-ray detection of Pictor A might be associated with the passage of a new VLBI component through the radio core, which appears to be a defining feature of high-energy emitting Fanaroff-Riley type II radio galaxies. We detect subluminal parsec-scale jet motions in the peculiar AGN PKS 0521−36, and we confirm the presence of fast γ-ray variability in the source down to timescales of six hours, which is not accompanied by variations in the VLBI jet. We robustly confirm the presence of significant superluminal motion, up to βapp ∼ 3, in the jet of the TeV radio galaxy PKS 0625−35. Our VLBI results constrain the jet viewing angle to be θ < 53°, allowing for the possibility of a closely aligned jet. Finally, by analyzing the first pc-scale multi-epoch images of the prototypical compact symmetric object (CSO) PKS 1718−649, we place an upper limit on the separation speed between the two mini-lobes. This in turn allows us to derive a lower limit on the age of the source. Conclusions. We can draw some preliminary conclusions on the relationship between pc-scale jets and γ-ray emission in radio galaxies, based on Fermi-LAT-detected sources with available multi-epoch VLBI measurements. We find that the VLBI core flux density correlates with the γ-ray flux, as seen in blazars. On the other hand, the γ-ray luminosity does not show any dependence on the core brightness temperature and core dominance, which are two common indicators of jet Doppler boosting. This seems to indicate that γ-ray emission in radio galaxies is not driven by orientation-dependent effects, as in blazars, in accordance with the unified model of jetted AGN.

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Robinson, B. J. "Science with the Australia Telescope (Invited Paper)." Publications of the Astronomical Society of Australia 7, no. 2 (1987): 220–26. http://dx.doi.org/10.1017/s1323358000022256.

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AbstractThe research now under way with the real-time 275 km Parkes-Tidbinbila interferometer is used as a guide to the initial science to be undertaken with the 319 km Australia Telescope (AT) Long Baseline Array. On the other hand, it is risky to guess at the new science likely to be attempted with the 6 km AT Compact Array at Culgoora; instead the potential that has been built into this array is discussed and a selection of basic questions in astrophysics is posed as a guide to significant science that might yield to new observers on a fresh instrument under the southern skies. In conclusion two questions are probed: Can discoveries be made by users of national facilities? Does the AT cross into new domains in the phase space of observations?

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Budding, E., B. D. Carter, M. W. Mengel, O. B. Slee, and J. F. Donati. "A Radio and Optical Study of the Active Young F Star HR 1817 (=HD 35850)." Publications of the Astronomical Society of Australia 19, no. 4 (2002): 527–33. http://dx.doi.org/10.1071/as02021.

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AbstractThis paper presents the results of a multiwavelength observational study of the active young F-type star HR 1817. The star was monitored at 4.80 and 8.64 GHz over 2 × 12 h allocations with the Australia Telescope Compact Array on 8 and 9 December, 2000. The Anglo-Australian Telescope was used for simultaneous optical spectropolarimetry during a 2 h period on 9 December.The low levels of observed radio emission have characteristics that are similar to those seen in other active stars, and a gyrosynchrotron mechanism is proposed to explain them; this is supported by the relatively low fractions of circular polarisation measured in HR 1817.Comparison of the emissions from 4.80 and 8.64 GHz shows a very strong cross-correlation peak, indicative of a common origin, although the shift of this peak indicates that 8.64 GHz variations tend to precede those at 4.80 GHz by, typically, ˜20 min.The optical spectropolarimetry reveals polarisation signals characteristic of surface magnetic fields, with profile changes indicating a complex dynamo-type magnetic topology is present on the star. This result makes HR 1817 the star with the earliest spectral type on which dynamo magnetic fields have been detected directly up to now.

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Ryan, Sean G., and Peter R. Wood. "Seeing Degradation within the Anglo-Australian Telescope Dome." Publications of the Astronomical Society of Australia 12, no. 1 (April 1995): 89–94. http://dx.doi.org/10.1017/s1323358000020105.

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AbstractRecent seeing measurements at the Anglo-Australian Telescope (AAT) point towards the thermal characteristics of the telescope itself, in particular the temperature difference between the mirror and the dome air, as the most important factor degrading the seeing, more so than the temperature difference between the inside and outside air. We present the findings, propose clarifying experiments, and discuss possible remedies. We set the realistic target for the AAT to achieve median seeing of 1·5″ rather than the current 1·8″.

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Wong, T., and A. Melatos. "Millimetre Science with the Upgraded Australia Telescope." Publications of the Astronomical Society of Australia 19, no. 4 (2002): 475–85. http://dx.doi.org/10.1071/as02015.

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AbstractA new astronomical window into the southern skies has been opened with the high-frequency upgrade to the Australia Telescope Compact Array (ATCA), which allows radio-interferometric mapping of sources at wavelengths as short as 3 mm. In anticipation of the upgrade's completion, a two-day workshop was held at the University of Melbourne in November 2001. The workshop covered a diverse range of fields, tied together by a common theme of identifying key areas where ATCA observations can have an impact. More than half of the talks were concerned with molecular clouds and star formation, with the remainder covering topics such as molecular gas in the Galactic Centre, Seyfert nuclei, and high-redshift objects. Some early results from the 3 and 12 mm prototype systems were also presented. In consultation with the speakers, we are presenting in this article a summary of the talks. The original slides are available from the ATNF website.

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Manchester, R. N., G. B. Hobbs, A. Teoh, and M. Hobbs. "The Australia Telescope National Facility Pulsar Catalogue." Astronomical Journal 129, no. 4 (April 2005): 1993–2006. http://dx.doi.org/10.1086/428488.

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Subrahmanyan, R., R. D. Ekers, L. Saripalli, and E. M. Sadler. "ATLBS: the Australia Telescope Low-Brightness Survey." Monthly Notices of the Royal Astronomical Society 402, no. 4 (March 2010): 2792–806. http://dx.doi.org/10.1111/j.1365-2966.2009.16105.x.

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Väisälä, Miikka, Jorma Harju, Maarit Mantere, Oskari Miettinen, and Malcolm Walmsley. "High-resolution Ammonia Mapping of the Protostellar Core Cha-MMS1." Proceedings of the International Astronomical Union 8, S292 (August 2012): 61. http://dx.doi.org/10.1017/s1743921313000410.

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AbstractThe nearby protostellar core Cha-MMS1 has been mapped in the NH3 (1, 1) line and the 1.2 cm continuum using the Australia Telescope Compact Array, ATCA. In addition, observations from Spitzer Space Telescope and Herschel Space Observatory are used to help the interpretation. An elongated condensation with a maximum length of 9000 AU is seen in ammonia. The condensation has a clear velocity gradient directed perpendicularly to the axis of elongation. The gradient can be interpreted as rotation around this axis. We suggest that the observed ammonia structure delineates a rotating envelope and dense gas entrained by a very young protostellar outflow.

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Cohen, Martin, Anne J. Green, Mallory S. E. Roberts, Marilyn R. Meade, Brian Babler, Remy Indebetouw, Barbara A. Whitney, et al. "G313.3+00.3: A New Planetary Nebula Discovered by the Australia Telescope Compact Array and theSpitzer Space Telescope." Astrophysical Journal 627, no. 1 (July 2005): 446–53. http://dx.doi.org/10.1086/430251.

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Sarma, A. P., W. M. Goss, A. J. Green, and D. A. Frail. "Australia Telescope Observations of the CTB 33 Complex." Astrophysical Journal 483, no. 1 (July 1997): 335–39. http://dx.doi.org/10.1086/304246.

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Osterberg, Jürgen, Lister Staveley-Smith, Joel M. Weisberg, John M. Dickey, and Ulrich Mebold. "A Search for NH3 in the Large Magellanic Cloud." Publications of the Astronomical Society of Australia 14, no. 3 (1997): 246–50. http://dx.doi.org/10.1071/as97246.

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AbstractWe report a search for the NH3 (J,K) = (1,1) inversion line in the Large Magellanic Cloud (LMC) using the Parkes 64–m telescope. Candidate positions were chosen with the help of recent H i data from the Australia Telescope Compact Array and published 12CO data from the Swedish–ESO Submillimetre Telescope. No detections of NH3 in emission were found at the positions surveyed. Upper limits are approximately 25 to 74 mK.

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45

Jauncey, DL. "VLBI in Australia ? A Review." Australian Journal of Physics 44, no. 6 (1991): 785. http://dx.doi.org/10.1071/ph910785.

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After two decades of Australian VLBI (very long baseline interferometry), high-resolution radio astronomy continues to be an active and fruitful research field. The status of Australian VLBI programs in astrophysics, astrometry and geodesy is reviewed and likely future developments are outlined. In addition to research programs with the Australian VLBI network, a number of successful collaborative projects are underway with overseas VLBI observatories. The inception of the Asia-Pacific Telescope will provide an important formal basis for fostering and extending international VLBI experiments in the Australian hemisphere. The APT will also serve a vital function in coordinating ground-based observations when the Soviet and Japanese VLBI space missions, Radioastron and VSOP, are launched in the middle of this decade. However, continued viable Australian participation in VLBI into the nineties will require new wide-bandwidth recording systems and an Australian VLBI correlator.

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Norris, R. P., M. J. Kesteven, R. A. Sramek, W. E. Wilson, J. W. Brooks, M. R. Calabretta, R. D. Ekers, G. J. Nelson, M. W. Sinclair, and A. C. Young. "2152–69: The First Image from the Australia Telescope." Publications of the Astronomical Society of Australia 8, no. 3 (1990): 252–53. http://dx.doi.org/10.1017/s1323358000023444.

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AbstractAlthough only three antennas of the Australia Telescope Compact Array are currently operational, we have made use of the technique of bandwidth synthesis to make an image of the radio galaxy 2152 – 69. The three baselines were used to observe the source at three different frequencies, effectively resulting in nine baselines, which have been used to produce an image with a surprisingly high dynamic range, and with a slightly higher resolution than any existing image.The production of such a worthwhile result, despite being made with a small subset of the capabilities of the Australia Telescope, bodes well for the future operation of the instrument.

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Tuohy, Ian R., and Michael A. Dopita. "The Lyman Far Ultraviolet Spectroscopic Mission (Invited Paper)." Publications of the Astronomical Society of Australia 7, no. 2 (1987): 173–84. http://dx.doi.org/10.1017/s1323358000022165.

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AbstractThe Lyman mission will undertake the first sensitive high resolution spectroscopic observations in the largely unexplored 912-1216Å region. This astrophysically critical wavelength interval is exceedingly rich in diagnostic spectral lines such as the Lyman series of atomic hydrogen and deuterium, the Lyman and Werner bands of molecular hydrogen and deuterium, and the resonance lines of numerous important species including CIII, NI-III and OVI. Lyman will have a major impact in all areas of modern astrophysics, with the most fundamental contribution being the determination of light element abundances in the local interstellar medium and in the intergalactic medium at low redshift. The mapping of hot gas (T ∼ 3 × 105K) and molecular hydrogen and HD in the disk and halo of our galaxy represent additional major objectives for which Lyman is uniquely qualified.The Lyman payload will comprise a grazing incidence telescope and three spectroscopic instruments: the prime spectrograph operating between 912-1250Å with a resolution of λ/ Δλ ∼ 30,000, a far ultraviolet spectrograph (1200-2000Å;λ/ Δλ ∼ 10,000), and an extreme ultraviolet spectrograph (100-900Å; λ /Δλ ∼ 300). Observations will be conducted from a highly efficient 48 hour elliptical orbit which will allow long un-interrupted exposures and real time operations. It is anticipated that Lyman will be launched by Ariane in 1996, and will have an operational lifetime of at least 5 years. Data reception and spacecraft control will be undertaken from ground stations in Spain and in Australia.Lyman is currently being studied at Phase-A level by Australia in close coordination with the European Space Agency. The scientific involvement is the responsibility of the Lyman Science Working Group, composed of members representing the various astronomical institutions in Australia. Funding to support the technical and scientific aspects of the mission is provided via the Australian Space Board and the Department of Industry, Technology and Commerce in recognition of the major opportunity that Lyman presents to the Australian aerospace industry.

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Velović, Velibor, M. D. Filipović, L. Barnes, R. P. Norris, C. D. Tremblay, G. Heald, L. Rudnick, et al. "Collimation of the kiloparsec-scale radio jets in NGC 2663." Monthly Notices of the Royal Astronomical Society 516, no. 2 (September 12, 2022): 1865–80. http://dx.doi.org/10.1093/mnras/stac2012.

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ABSTRACT We present the discovery of highly collimated radio jets spanning a total of 355 kpc around the nearby elliptical galaxy NGC 2663, and the possible first detection of recollimation on kiloparsec scales. The small distance to the galaxy (∼28.5 Mpc) allows us to resolve portions of the jets to examine their structure. We combine multiwavelength data: radio observations by the Murchison Widefield Array (MWA), the Australian Square Kilometre Array Pathfinder (ASKAP) and the Australia Telescope Compact Array (ATCA), and X-ray data from Chandra, Swift, and SRG/eROSITA. We present intensity, rotation measure, polarization, spectral index, and X-ray environment maps. Regions of the southern jet show simultaneous narrowing and brightening, which can be interpreted as a signature of the recollimation of the jet by external, environmental pressure, though it is also consistent with intermittent active galactic nuclei or complex internal jet structure. X-ray data suggest that the environment is extremely poor; if the jet is indeed recollimating, the large recollimation scale (40 kpc) is consistent with a slow jet in a low-density environment.

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Petrov, Leonid, Elizabeth K. Mahony, Philip G. Edwards, Elaine M. Sadler, Frank K. Schinzel, and David McConnell. "Australia Telescope Compact Array observations of Fermi unassociated sources." Monthly Notices of the Royal Astronomical Society 432, no. 2 (April 2013): 1294–302. http://dx.doi.org/10.1093/mnras/stt550.

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Gillingham, P., M. Pettini, M. Bessell, L. Cram, and K. Ogura. "A Coudé Auxiliary Feed for the AAT: a Focus for International Co-operation in Optical Astronomy." Publications of the Astronomical Society of Australia 9, no. 1 (1991): 160–61. http://dx.doi.org/10.1017/s1323358000025406.

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AbstractIn 1988, a very powerful and versatile coudé echelle spectrograph was installed at the Anglo-Australian Telescope. Since then it has been winning about 30% of AAT time and has been highly productive scientifically. Therefore, using a coudé auxiliary telescope (CAT) to give the spectrograph more use and to free the AAT for other work is a very attractive possibility, particularly if the CAT can give a sensitivity similar to that obtained with the 3.9-metre telescope. While a conventional CAT with such performance would be very expensive, a much cheaper instrument should approach this goal, at least for high resolution spectroscopy. Even so, the cost could not be met in a reasonable time within the AAO’s budget; hence, additional international collaboration is being sought.

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Journal articles on the topic 'Australian Space Telescopes'

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