Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.

An enormous effort is underway worldwide to attempt to detect gravitational waves. If successful, this will open a new frontier in astronomy. An essential portion of this effort is being carried out in Australia by the Australian Consortium for Interferometric Gravitational Astronomy (ACIGA), with research teams working at the Australia National University, University of Western Australia, and University of Adelaide involving scientists and students representing many more institutions and nations. ACIGA is developing ultrastable high-power continuous-wave lasers for the next generation interferometric gravity wave detectors; researching the problems associated with high optical power in resonant cavities; opening frontiers in advanced interferometry configurations, quantum optics, and signal extraction; and is the world's leader in high-performance vibration isolation and suspension design. ACIGA has also been active in theoretical research and modelling of potential astronomical gravitational wave sources, and in developing data analysis detection algorithms. ACIGA has opened a research facility north of Perth, Western Australia, which will be the culmination of these efforts. This paper briefly reviews ACIGA's research activities and the prospects for gravitational wave astronomy in the southern hemisphere.