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RUBY:

Hi, I’m Ruby Jones. Welcome to 7am’s summer series: an exploration of big ideas with some of our favourite contributors and thinkers.

When we talk about the most significant events of the last year, perhaps the one that will have the biggest impact on humanity actually took place far above the earth’s atmosphere.

Up there, in orbit around earth, is one of the most powerful tools humans have ever had to hunt for the origins of our universe – and for alien life.

The James Webb space telescope has the ability to look so far and with such clarity that we can get an insight into a period of time that our best scientists have only ever speculated about: the cosmic dark ages.

Today, Director of the Space Technology and Industry Institute at Swinburne University, Dr Alan Duffy on why this year marked a new beginning for our understanding of the universe.

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RUBY:

Alan, In 2021, the James Webb telescope was launched into space, and then six months later, it began transmitting images back here to us. And these are the most detailed and comprehensive images of space that we've ever seen. So to begin with, can you tell me about just how much of a feat it was getting the telescope out into space? And I guess the footsteps it's following in?

ALAN:

This is an incredible undertaking, not least of which because the telescope is six and a half metres across mirror is larger than the rocket it launched in. So it was launched, folded up like a rose and then in space unfurled in a perfect origami like structure to create the mirror and the protective tennis court sized solar shade to keep the whole thing nice and cool. And that scale of the telescope, the James Webb Space Telescope or JW, it had to be that big and that expansive because it was the successor to arguably one of the most famous and certainly one of the most productive telescopes in history, the Hubble Space Telescope.

Archival tape -- Hubble launch crew:

“T-6, 5, 4, 3, 2, 1 and lift off! The space shuttle discovery with the Hubble space telescope - our window on the universe!”

ALAN:

So if we cast our minds back. This was launched in 1990. And by no means was the first telescope in space, but certainly has been, I think, the most famous. And the images coming off that telescope have really become cultural icons.

Archival tape -- Barbara Mikulski:

“The Hubble telescope has been the greatest telescope since Galileo invented the first one.”

Archival tape -- Hubble success:

“It has allowed us to really peer back in time near the beginnings of the universe about as far out in space as as we can imagine within a couple hundred million years of the origins of the universe.”

Archival tape -- Reporter:

“Images include the planet Jupiter, an array of stars across a wide colour range, and stars coming to life in the chaotic Carina Nebula.”

ALAN:

I had pictures of them on the wall, but maybe that's not surprising, I'm an astronomer, but so too did normal people, right? So this is, I think, the impact that the Hubble has had.

So for a telescope to meet and indeed, of course, surpass the Hubble, it had to be much larger. And in particular, it also had to look in a different kind of light. Hubble is in the optical and it's the normal kind of light that you and I can see in. When JW was proposed, the idea was to shift into the infra-red. So this is a longer kind of wavelength of light. You can see different phenomena in the space. You can see further away indeed as well. But because it's a longer wavelength to get the same kind of detail, you had to have a much larger mirror.

So inevitably NASA was driven to select an absolutely absurdly sized six and a half metre mirror. Folded this thing up.

Archival tape -- JW launch:

“and we have engine start…and lift off…Decollage! Liftoff! From a tropical rainforest to the edge of time itself.”

ALAN:

It launched in December just last year, so this was the ultimate Christmas present; it successfully launched, which was absolutely nerve racking for all of us.

Archival tape -- JW launch:

“Separation Webb Space telescope - go Webb!”

Archival tape -- JW launch:

“James Webb space telescope amidst applause here in the mission control centre, now taking its first steps in pursuit of cosmological discovery.”

ALAN:

And then a mere six months later, the first images have come back and they are magnificent. These are even just by eye, no fancy stats. You cannot believe how crisp and sharp and clear the images are.

RUBY:

Can you tell me a little bit more about them? What is it that we're actually seeing on those images? And what was it like for you when you saw some of those first ones come through?

ALAN:

Yeah. So the first tranche of images have been really exciting range of targets. We've seen our own solar system, but so too distant alien worlds and even very distant clusters of galaxies. And then behind the cluster of galaxies you have these tiny little, almost imperceptible red dots scattered throughout the image. And these are galaxies that are so far away from us that we're seeing them as they were when the light first left just two or 300 million years after the Big Bang. These are baby galaxies, perhaps the first galaxies ever formed. And we hope in the coming years we may yet see the first star ever formed in the universe. That is the power of JWST, it just completes our understanding of how our Milky Way galaxy, our sun and indeed, of course, our own planet and ourselves came to be. It is the missing years that Hubble didn't quite have the power or the wavelength coverage to allow us to see. JW just gives us that missing piece of our own story.

RUBY:

And in terms of the, I suppose, scientific significance of these images that we've been seeing in the kind of six months or so since they started being transmitted back to us, I mean, how significant are they? And are there any, I suppose, discoveries within that that have really excited the scientific community?

ALAN:

Yeah, well the first image that came off the JW that was presented, in fact, the president no less shared that image with the public.

Archival tape -- Joe Biden:

“Tomorrow when this image is shared with the world, it’ll be a historic moment, for science and technology, for astronomy and space exploration, for America and all of humanity.”

ALAN:

It broke all the records for the most distant galaxies ever seen the youngest galaxies ever imaged.

Archival tape -- President Biden:

“We can see possibilities no one has ever seen before, we can go places no one has ever gone before.”

ALAN:

Those kinds of discoveries were ground breaking, but they certainly were expected. This is why such an enormous telescope has been built was to collect enough light so you could see tiny, faint things and very, very far away. More recently, we've also seen the light from a star pass through the air of an alien world on its way to us. And that has the effect of changing that starlight ever so slightly. And in particular, you can actually measure what chemicals are in the air that is causing that change in the light. And it was an ability that we had hoped JWST would have to reveal certain chemicals in the atmosphere of these alien worlds, planets around other stars that may indicate the presence of life. So we are hoping to detect those kinds of chemicals and those kinds of combinations that might allow us to begin to hone in on locations that are not just potentially habitable for life, but perhaps inhabited. Now, there's a lot of work to be done, but this was a really exciting first discovery that showed all our hopes for a JW and the ability to make those kinds of measurements are warranted. It is performing astoundingly well.

RUBY:

Right. So it sounds like this telescope, then it could help us discover whether or not there is life on other planets out there in the universe.

ALAN:

Yeah, absolutely. This is an alien hunter. Maybe set the context a little bit. Another space telescope from a few years back. Kepler It was looking for occasions where a planet will pass between us and its star and block a little bit of the light. So if you see this star getting dimmer every, say, 80 days, then you know you've got a planet with a year that lasts 80 days and you can start to make infinities about the size of the world, how far it is from its star, and hence the temperature on that world. What we've done is now seen thousands of alien worlds, and when you run the numbers, there's a few hundred billion stars in our galaxy alone. Now, thanks to Kepler and some other telescopes, we've been able to hone in on exactly how many might have a world like Earth around a star like the Sun and Venus, similar kinds of conditions. And the last time I did the calculation, we were sitting at about 4 billion Earth twins or Earth-like worlds around sun-like stars. So there's a lot of worlds out there.

RUBY:

Wow. A lot of potential.

ALAN:

A lot of potential! And this is why we're so excited about following up with these kinds of measurements by JW.

Now, it's not a confirmation; there are natural geological ways that might happen. You have to rule all of those things out before you get to make that grand claim. But right now, we have the technology to detect the signatures of alien life in the atmospheres off of distant planets. And I think that that is a truly remarkable moment for humanity, and we might just need to be patient for a few more years. But if it's out there, we'll be finding it sooner or later.

RUBY:

We'll be back after this.

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RUBY:

Alan, just to take a step back, it sounds like what this telescope is doing is that it's able to probe this particular time period that so far we haven't managed to get any information on because of the technology that we've had up until this point. And I believe that that time period is referred to as the Cosmic Dark Ages. Can you tell me a bit about the Cosmic Dark Ages? How long ago were they? And why is it that up until now we haven't been able to really probe that era?

ALAN:

Right. So this is a time in our universe's life where essentially the stars had not yet formed. So it was dark. There was just large clouds of gas. They were slowly falling under the gravity of this mysterious component of our universe called dark matter.

But these clouds of gas fall together. They get denser and the middle gets hotter, higher pressures. And eventually the conditions get so intense that you can smash hydrogen atoms together and you begin to have a nuclear furnace burning. In other words, you have created a star, and then those stars begin to form all over the universe. And over the period of a few hundred million years, they essentially light up the universe that is this period of cosmic dawn.

So the period of those few stars forming and indeed, you know, those kinds of first galaxies is known as the Dark Ages. So those first stars, that's one of the primary missions to see what those first stars look like.

And it was a very different universe, very uncertain physics. And we really do need these kinds of observations to test our models, to understand how you build a galaxy from essentially the big bang onwards. And that's what the JWST is going to be focussed on.

RUBY:

And so far we've been talking about the things that JWST is designed to probe, the questions that scientists want answered, and the things that might be discovered by using this tool. But there's going to be surprises, isn't there? There are things that we can't really imagine right now that this telescope is going to encounter.

ALAN:

That’s absolutely right. When you build something of the power of the capability of JW, you are going to make huge and unexpected discoveries. And it's you know, it's obviously then hard to predict, right. This the unknown unknown. But what we can at least do is look to the example of Hubble and say, after decades of operation, of tremendous discoveries, how many of the top discoveries were actually anticipated were part of the original mission plan for Hubble? And I think from memory, one of the top ten were expected and had been planned. So nine of the top ten discoveries of Hubble were completely unknown to science when Hubble was commissioned and launched. So that's why we are so excited with JW, we have something even bigger, even more capable, we are so looking forward to being amazed and astounded by the discoveries, the unexpected discoveries that it makes. How do you sort of search for the unknown, the unexpected? And typically you just have to do that with a very open mind and lots of grad students. Right, who are very willing to trawl through the data. But I could well imagine that it isn't the, you know, so-called professional astronomer who makes a lot of these most astounding discoveries because, you know, we're going to be looking forward the thing that we wrote a grant to search for, and it's when the public gets their hands on that data and the tools to enquire into it that they may yet make those truly ground breaking unknowns, knowing that we've got this next generation facility that I've spent my entire career looking forward to now finally deployed and the images being downloaded. It's kind of shocking to me still that finally the big moment has arrived I don’t know how else to phrase it. It's kind of like waiting for the World Cup and then your team's in the World Cup and you and your now just trying to figure out, oh, are we going to win it right. Like that? The excitement is you sometimes have to pinch yourself to come to the realisation that you're you know, it's not a dream, it actually works beautifully. It's all worked, worked out.

RUBY:

And so do you think that the JWST, much like the Hubble before it, is really likely to transform our understanding of the universe and our place within it?

ALAN:

Absolutely. It's I think it's this search for alien life, the ability to measure the first stars and really tell us how it is that objects like our galaxy began to grow, as well as that just that vast potential for the unknown discoveries. These are incredibly challenging questions, but they're fundamental questions. They are those very most basic wonderings that I hope many of us have had as we've looked up at the night sky and wondered, Are we alone or how did this all get there? JWST is a telescope that can help us answer those fundamental questions. It's a heck of a time to be an astronomer.

RUBY:

Alan, thank you so much for your time.

ALAN:

Thank you so much.