American astrophysicist Penny Sackett became Stromlo’s first female Director in 2002. She completed a PhD in theoretical physics in 1984 and worked as a science journalist and a university physics instructor before beginning her astronomical research in the Netherlands, and then the Institute for Advanced Study at Princeton. For twenty years, her work focussed on microlensing - the effect that the gravity of distant objects has on the path of light from a more distant source to an observer, and on the discovery and characterisation of planets around other stars.  She founded the PLANET microlensing collaboration, which made substantial contributions to the understanding of extrasolar planets and stellar atmospheres.

Sackett inherited a world-class research facility when she arrived at Mount Stromlo in 2002, and was committed to maintaining this standard of excellence. But Sackett was confronted with a much greater challenge – only six months into her directorship, the Observatory was devastated by a catastrophic bushfire. Sackett’s immediate task was to rebuild. The fires forced the Observatory to focus on its strength – the development of astronomical instrumentation. Sackett thus oversaw the construction of the Advanced Instrumentation Technology Centre (AITC) – a world-class facility that was designed to facilitate the manufacture of complex instruments for the Extremely Large Telescopes (telescopes with a mirror diameter larger than 20m). The first stage of the AITC was opened by Sackett in 2006.

Perhaps Sackett’s most visionary decision was for Mount Stromlo to contribute to the development of the Great Magellan Telescope (GMT). Consisting of seven 8.4m mirrors, this Extremely Large Telescope is due for completion in 2020. The ANU is tasked with manufacturing an Integral-Field Spectrograph for the GMT, which will allow astronomers to record spectra from each point across the field of view simultaneously. Despite the destruction caused by the 2003 firestorm, Penny Sackett ensured Mount Stromlo remained at the forefront of astronomical research and development.