Position: Professor of Radio Astronomy, Curtin University and Director, Murchison Widefield Array.
Field: Radio Astronomy.
The universe as a laboratory
Do you want to explore the universe using amazing instruments? Then become a radio astronomer, like Dr Melanie Johnston-Hollitt. Melanie studies the physics of galaxy clusters, using radio, optical and X-ray telescopes. With the universe as a laboratory, she gets to use some very expensive and advanced instruments, including Australia’s largest radio telescope and an observatory in orbit above the Earth.
We first met at Melanie in 2009 when she was at Victoria University of Wellington, as Associate Professor at the School of Chemical and Physical Sciences. There have been many changes since then, but not for her on-going passion for radio astronomy
An early fascination in astronomy
Melanie’s fascination began as a young child. She would sit with her Nana on the back door porch and look up at the night skies while her Nana told her stories. This fired Melanie’s imagination, and from that early age, she knew she would pursue a career in astronomy.
Radio astronomy – a global science
Melanie is part of a worldwide community of scientists. Her work takes her to research facilities and conferences around the world, but she can also stay in her office and drive telescopes on and above the Earth.
Of course, not everyone can just link up to the internet and drive telescopes in other countries. There is a lot of competition for time using the very expensive and high-quality instruments. To get time with the XMM-Newton orbiting X-ray observatory, run by the European Space Agency, Melanie has to be in the top 10–15% of applicants from all round the world.
Melanie’s research has taken her round the world, even if not into space. After completing her PhD in astrophysics in Australia, Melanie moved to the Netherlands to work on the design of a new radio telescope. She returned to Australia in 2004 to join the University of Tasmania. While there, she and her students used radio telescopes in Australia, America and India. Melanie came to New Zealand, joining Victoria University of Wellington in January 2009, where she started recruiting students to work with her using the world’s major radio telescopes.
Square Kilometre Array
In November 2011, the SKA Organisation was formed, and Melanie was appointed to the Board of Directors for the Square Kilometre Array project.
In 2012, it was announced that the SKA will be split over the South African and African sites and Australia. Melanie traveled regularly across the world, with her work on the Square Kilometre Array, whose headquarters are in London.
SKA will have a life span of at least 50 years. By 2030, the project will have been scaled up to 2,000 dishes in South Africa and one million antennae in Australia.
All these dishes and antennae will result in extremly large amounts of data – it is estimated the array could generate an exabyte a day of raw data! This poses challenges for data storage and processing. Melanie was the task leader for the Science Pipeline of the SKA Science Data Processor Work, leading a team of staff and students at Victoria University who were looking at ways to process the data such as algorithms to identify patterns within the data. Melanie says, “SKA is, in a sense, a prototype for what the world of data analytics will look like in the future. Looking for patterns in complex data sets is what is needed for the SKA and it’s what will be needed for finance, health, meteorology, the internet and pretty much everything where humans will have to deal with big data.”
New Zealand is a great place to be doing science just now.
Melanie is a very busy woman. In addition to her work with SKA, she is amongst other things Executive Board Chair for the Murchison Widefield Array Radio Telescope and a Faculty Member of Singularity University, a Silcon Valley 'think tank' that offers educational experiences focused on exponential technologies.
In early 2017 she became CEO and founder of Peripety Scientific Ltd, an independent research organisation specialising in radio astronomy research and consultancy based in Wellington. She resigned from Victoria University of Wellington in September 2017 and took up the position of Professor of Radio Astronomy at Curtin University and Director of the Murchison Widefield Array.
Listen to Melanie talking about her work and how to best meet the science challenges of the next generation instruments in the big data era in her TEDxChristchurch talk.
Listen to Veronika Meduna talking about her field trip to the Square Kilometre Array building site in Australia for RNZ’s Our Changing World.
Hear Melanie Johnston-Hollitt talk about probing galaxy clusters in this RNZ audio from the Our Changing World series.
This article was updated in 2018.