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Why is the sun at the centre?
CrowdScience
May 26, 2023

It may seem like a simple question but could you explain why the earth revolves around the sun? That is what listener Josh from New York wants to know. For much of human history we thought everything revolved around us, literally. So how did humans come to the conclusion that we're not the centre of the universe? And how did the scientific process help us uncover the true order of things?

Looking through telescopes from the vantage point of Australia, host Caroline Steel speaks with astronomers and physicists about the bumpy scientific journey to arrive at this discovery that we now take for granted. Delving into Indigenous astronomy with researcher Peter Swanton, Caroline questions whether Western scientists were really the first ones to grasp this understanding of our solar system.

And at the Sydney Observatory, stellar astrophysicist Devika Kamath and Sydney Observatory host Nada Salama show Caroline some of the clues up in the sky that astronomers in the 1600s used to deduce that there was something wrong with earlier models of our solar system.

Rhett Allain from Southeastern Louisiana University helps break down the physics concepts at play when it comes to the motion of our planets and the sun.

Through her exploration of a seemingly simple question, Caroline asks some big questions as she looks up to the stars – about life, the universe, and the nature of science itself.

Producer: Sam Baker Presenter: Caroline Steel Editor: Richard Collings Production co-ordinator: Jonathan Harris

Featuring: Devika Kamath, Astrophysicist, Macquarie University Rhett Allain, Associate Professor, Southeastern Louisiana University Peter Swanton, Indigenous Research Associate, Australian National University

(Photo: Caroline and Devika, Sydney Observatory)

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Jun 5, 2026
Do plants have personalities?

CrowdScience listener George is showing Alex Lathbridge around a small, dark, and extremely hot shed, just outside the city of Accra in Ghana. Inside are row after row of shelves, stacked high with bulging grow-bags. And out of some of them, gorgeous cascades of oyster mushrooms are bursting into bloom.

We’re on George’s mushroom farm, and he’s noticed something interesting. Even though the conditions in his grow-shed are tightly controlled – they have exactly the same food, water, and light as each other – nevertheless, they respond differently. Some are more vigorous than others, some bloom quicker, others last longer, and some are more tolerant when the conditions change. And this got George wondering. Could ‘brainless’ lifeforms like mushrooms, and plants, have different ‘personalities’? Do they experience the world differently, and live their lives differently from each other? Alex Lathbridge is on the case.

He visits the PGRRI, the Plant Genetic Resources Research Centre, for a quick lesson on genetic variation in the plant world. Plants are all different at the genetic level, and it’s those differences which can result in a tastier fruit, or a hardier crop. But would we call traits like these personality?

In the Minimal Intelligence Lab in the University of Murcia in Spain, Paco Calvo thinks that we absolutely should. He studies plant intelligence, and points Alex to a whole host of examples of plants being smart in ways which might surprise you. Each one is an individual, and if we can only slow down enough to appreciate them properly, we’d be able to understand them better too.

Back in Ghana, Alex meets plant physiologist Dr Acheampong Atta-Boateng, in the beautiful grounds of Aburi Botanical Gardens, to meet some of these plants for himself. And he discovers that there’s a whole world of smart, resilient, and resourceful little organisms in the plant world, full of personality, if you know where to look. Who needs a brain!?

Presenter: Alex Lathbridge

Producer: Emily Knight

Editor: Ben Motley

(Photo: Drawing of a face and smiling eyes on a sunflower flower - stock photo- Credit: Jose A. Bernat Bacete via Getty Images)


29min 16sec


May 22, 2026
Why am I an introvert?

CrowdScience listener Daniel in Accra, Ghana is an introvert. Or at least, he thinks he is. And he’s worried that his preference for quiet spaces and lower social interaction might be holding him back in life. But what is introversion really? How do introverts and extroverts see the world differently? And is it better to be one or the other?

Presenter Alex Lathbridge spends his working days talking to interesting people like Daniel. He loves meeting people, and talking to them too, yet he also thinks that deep down, he might be an introvert. To understand how and why people come to be introverted or extraverted, and what’s happening in the brain, he pays a visit to neuroscientist Dr Thomas Tagoe from the University of Ghana Medical school, for a peek inside the mind. Turns out, introverts aren’t shy, and definitely aren’t anti-social either, despite what people might assume. The difference is more about how we process stimulation, and at what point we find it all a bit too much to process. Although sometimes it might feel like the world is built for the extraverts out there, Thomas offers some reassurance. There are huge benefits to being introverted too, and there’s room in the world for all the different personality types to thrive.

But how about in the workplace? Daniel is worried that his introversion could be holding him back at work. He feels like being good at your job is not always enough – you need to be able to network, charm people, and “work the room” if you want to succeed. So, Alex heads for the Methodist University of Ghana to meet Professor William Baah-Boateng, who has studied the effect of all the different personality types on their performance in the workplace. Is there a place for the introverts of this work to make their mark?

Presenter: Alex Lathbridge

Producer: Emily Knight

Editor: Ben Motley 

(Photo:A view of a woman's eye looking through a hole in some colorful paper-Stock Photo - Credit:PeopleImages via Getty Images)


26min 28sec

Why is the sun at the centre?

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