60 Years of Science Wonder – Happy Birthday, Dish

As Australians, we are known to have a deep connection and treasure home-grown things that make a big mark on the world stage. And when it comes to astronomy, nothing creates more of that warm fuzzy feeling in your chest, like when we hear about or look upon one of our most iconic instruments to have ever been developed, the CSIRO Parkes radio telescope.

For most of us, these days – the story of The Dish (as it’s colloquially named) is cemented in the back of our minds through the wonderful film The Dish, released 21 years ago – telling the story (through a fictional narrative) of the important role played by the telescope during the historic Apollo 11 Moon landing in 1969.

Sample a random small portion of the population, and I guarantee that you’ll find one or more people who can tell you a tale about a time they visited the small town of Parkes in central NSW, to gaze upon the giant structure as it collected data from the cosmos above.

Others will tell you about their experience on that momentous day in July 1969 – as their classes were suspended and they crammed into rooms to watch a black and white screen of images, of humans, who for the first time were setting foot upon an entirely new world. Those images, coming from Australian telescopes (at first from the Honeysuckle Creek antenna, followed by the Parkes radio telescope) before beaming across the planet.

As a nation, there is no other large-scale scientific instrument we are all connected to emotionally, as we are to our beautiful Dish. And what a mighty workhorse it has been for science, for astronomy and Australian research. World-class. World-leading.

I’m probably one of the luckiest humans alive – as a teenager I learned about these fascinating objects known as pulsars, which were studied in detail using instruments like the Parkes radio telescope.

Oh, was I hooked. I knew then and there what I wanted to be when I grew up. My heart and mind gravitated towards these odd, mind-boggling objects in deep space that seemed (at the time) to defy the laws of physics, and they were being discovered only a few short hours drive away from where we lived.

I begged my mum to take us on road trips out to Parkes so we could see it, see the place where the signals from these pulsars were arriving, but we never got to go for a variety of reasons. That didn’t stop me from devouring any information I could get my hands upon about the telescope for the next few years.

But my dream eventually would come true, after a very slow start, I now get to do what I always wanted to do – study pulsars using the Parkes radio telescope. And that’s what makes me really lucky.

In a few days, 31 October to be exact, the Parkes radio telescope (owned and operated by Australia’s national science agency, CSIRO) celebrates its 60^th anniversary of being in operation. It’s rather humbling to think that this wonderful antenna has been staring at the skies for six decades, revealing so many things we had never known about the Universe until it came along.

Even more so for me is the fact that there are so many stories of researchers and scientists who have come before me – who must be feeling the same sense of connection to this instrument. They’ve all got their own story to tell, trials and tribulations, moments of frustration and moments of soaring, all centred around The Dish.

And what a life it has had.

The telescope itself is massive, something that dawns upon you when you first see it in real life. Its 64-metre diameter paraboloid dish is big enough to fit the entire length of an Olympic swimming pool in, with seven metres to spare on either side.

Part of what makes the telescope cosmetically appeasing is the lower half – a cream-coloured cylindrical concrete structure, rising only three stories high and marked with windows around the circumference, like a lighthouse. The equipment, electronics and processing systems are all kept here.

But the real science magic comes from the upper half – which weighs in at 1,000 tonnes – heavier than two Boeing 747s. It’s up here that all the collecting and steering of The Dish occurs. Remarkably, the top half of the telescope is not fixed to the concrete structure below, and simply just sits there. 

It took about three years to build the telescope and needed a lot of new innovation, technology and engineering to be tackled at the time. It was the first of its kind of design in the world, but not the last – with similar dish antennas replicated in Canada, Germany, the USA and Spain.

The aluminium panels and mesh that make up the surface of the telescope are designed to reflect radio light (with wavelengths from a few millimetres to several metres) into the receiver cabin, located 27-metres above. Here, powerful instruments like the Ultra-Wideband Low-Frequency (UWL) receiver (another CSIRO innovation) collect an abundance of signals across a frequency bandwidth that starts around 700 MHz running through to 4 GHz.

In 1995, the telescope was declared a national engineering landmark by Engineers Australia, and in 2020 it was both heritage listed and provided with a complimentary traditional Wiradjuri name, Murriyang.

To date, it’s still considered a world-class instrument, especially since it has been made about 10,000 times more sensitive from when it first commenced operations, through a number of technology and hardware updates. These days, you don’t even need to be at The Dish to drive it – in fact, all of the many observations I’ve run have been by remoting into the telescope’s systems from my home in Sydney.

The field of astronomy and astrophysics have been completely changed, thanks to the historical contributions made by Parkes radio telescope. Some highlights include:

• Discovery of over 2,500 new galaxies in our local region through the H1 Parkes All-Sky Survey

• Mapping the hydrogen gas across the Milky Way in unprecedented detail in the Galactic All-Sky Survey

• Helping confirm the discovery of quasars – some of the most distant objects discovered

• Discovery of more than half of all known pulsars

• Ongoing participation in measuring pulsars for the purpose of detecting gravitational waves through the Pulsar Timing Array project

• The discovery, within archival data and through observation, of mysterious fast radio bursts

Along with science achievements, the telescope has also been used for interplanetary space science and communications, with a history of working with NASA and the European Space Agency that includes:

• Tracking interplanetary space missions as far back as 1962 with the Mariner 2 Venus fly-by, through to missions like the Giotto spacecraft and both the Galileo and Cassini missions to Jupiter and Saturn

• Ongoing support for various Martian missions

• Relaying communications such as those of the Apollo missions, including assisting with the Apollo 13 emergency in 1972

• The search for radio signals from Extra-terrestrial technologies through the Breakthrough Listen project

• Working with the Very Long Baseline Interferometer (VLBI) project – which helps track the movement of the tectonic plate that Australia resides on.

• The Dish has also been used to track the most distant human-made objects in history, the Voyager space probes, as they progressed to the edge and beyond of our Solar System.

The knowledge gained from 60 years of experience with the Parkes radio telescope is now also flowing through to the next generation of telescopes, such as the CSIRO ASKAP out in Western Australia, and eventually onto Australia’s first mega-science project, the SKA.

Historically, the Parkes telescope has been able to survey a large portion of the sky due to technology that looks at different parts of the sky, using a multibeam receiver (where each beam sees a different part of the sky). This unique innovation has now been further advanced and is currently being utilised on ASKAP, as the phased array feeds, also known as a PAF. The PAF has the ability to scan 36 individual beams, and when combined with ASKAP’s 36 dishes spread across a 6-kilometre baseline, it turns the telescope into one of the most powerful radio instruments in the world.

Discoveries made at Parkes, such as the first detection of the mysterious fast radio bursts, are now being followed up with telescopes like ASKAP, finding plenty of new events and increasing our knowledge across a range of areas.

And it’s not just researchers who are getting in on the action – even high school students from across the country have been getting involved, with a chance to drive The Dish and collect real scientific data that is used by astronomers, through the Pulse at Parkes program. This CSIRO initiative is one way that the telescope is being used to inspire the next generation.

These days I get to spend my time poring over the enormous volumes of pulsar data that I’ve collected using the wonderful Parkes radio telescope for both my own research and that of other projects (like the Parkes Pulsar Timing Array project). I’ve had a few visits to the telescope where I listened and learned about the telescope’s history, operations and ongoing daily management from legends like CSIRO’s Dr John Sarkissian, who’s been part of the Parkes story for many years now.

Mum called me the other day, after seeing me share some of my findings and excitement about using The Dish to observe pulsars and said that she is now really wanting to go and see the telescope herself – a trip we are already planning, for post-pandemic times. Funny how things come around.

Every day I am grateful for the opportunities I have with the telescope, but more so, deeply humbled knowing that my story is one of many tied to that beautiful instrument. And that a chorus of stories, just like mine, but in the thousands, are all centre around the single-dish telescope in the middle of a sheep paddock, out at Parkes.

I really am one of the luckiest humans to be able to say this.

Happy birthday, Dish. And thank you.

We acknowledge the Wiradjuri people as the traditional owners of the Parkes radio telescope observatory.