Enceladus' Ocean Secrets, Titan's Wobbling Atmosphere, and Venus' Water Revelation

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Avery: Welcome back to Astronomy Daily, the

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podcast that brings the cosmos down to

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Earth. I'm your host, Avery.

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Anna: And I'm your other host, Anna. Uh, it's great

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to have you with us. We have an absolutely

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packed show for you today with news that

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spans our solar system.

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Avery: We are starting in the outer solar system

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with some incredible new findings from not

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one, but two of Saturn's moons.

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First up, Enceladus, which is looking

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more and more like a prime candidate for

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hosting extraterrestrial life.

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Anna: Then we'll stay in the same neighborhood to

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visit Titan, Saturn's largest moon, where

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its entire atmosphere appears to be doing

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something very strange, something scientists

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are comparing to a, uh, gyroscope.

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Avery: From there, we're taking a big leap inwards,

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all the way to our planetary neighbor,

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Venus. You might think you know Venus, but

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a fresh look at some very old data has

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turned our understanding of its clouds

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completely on its head.

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Anna: And to wrap things up, we'll bring it all

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back home. A new survey from Australia

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reveals a fascinating and perhaps slightly

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worrying gap between how much people support

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the space industry and how much they actually

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know about it.

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Avery: It's a journey from potential alien oceans

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to public opinion polls, so let's not

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waste any more time.

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Anna, uh, why don't you start us off with the

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exciting news from Enceladus.

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Anna: My pleasure, Avery. This story is a

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beautiful example of a mission that just

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keeps on giving. The Cassini spacecraft

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gave us two decades of incredible insights

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into Saturn. And even years after the mission

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ended, scientists are still mining its data

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for gold.

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Avery: And it seems they've struck a new vein.

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This is about those amazing water plumes,

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right? The ones Cassini actually flew

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through?

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Anna: That's the one. Almost 20 years ago,

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Cassini flew through plumes of water

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bursting from cracks in the icy surface of

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Enceladus. Now, a new analysis of

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that fly through data has confirmed what many

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had hoped, that complex chemical reactions

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are happening within the Moon's hidden

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subsurface ocean.

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Avery: That sounds huge. When we talk about

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searching for life, we're always looking for

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certain key ingredients. What does this new

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finding tell us?

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Anna: Well, it essentially affirms that Enceladus

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has all three of the major conditions

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necessary for a habitable environment, at

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least as we understand it. You need liquid

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water, which we know the Moon has, in its

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subsurface ocean. You need a source of

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energy, likely from hydrothermal vents on the

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ocean floor. And you need a specific

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set of chemical elements, the building blocks

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of life.

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Avery: And this new analysis adds more to that

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third category. The Chemical building blocks.

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Anna: Exactly. They found organic

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molecules, some new ones they hadn't detected

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before in the fresh ice grains that were

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ejected directly from the ocean. This

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included molecular fragments that potentially

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contain nitrogen and oxygen, which are

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crucial for life as we know it.

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Avery: So this is direct evidence of complex

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chemistry happening right now in that ocean.

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And Frank Postberg, one of the co authors,

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made a really important point about this,

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didn't he?

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Anna: He did. He emphasized that these molecules

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were found in freshly ejected material.

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This proves that the complex organics Cassini

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previously detected in Saturn's E ring

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aren't just the result of being zapped by

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radiation in space for a long time. They are

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being actively produced or are readily

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available right there in the ocean.

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Avery: So it's an active, chemically rich

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environment. And I believe another scientist

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on the paper, Nozair Kawasha, added that

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there are many possible chemical pathways

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that could lead from these simple organic

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molecules to more complex

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biologically relevant compounds.

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Anna: That's right. It significantly enhances the

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likelihood that the moon is habitable.

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We have to be clear, this is not evidence of

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life itself. But it is perhaps the

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strongest evidence yet that an environment

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that could support life exists, exists

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right now in our own solar system.

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Avery: Well, let's not leave the Saturn system just

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yet, because its biggest moon, Titan, is also

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making headlines with some very unusual

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behavior.

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Anna: That's right. If Enceladus is all about its

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hidden ocean, Titan is famous for its

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thick, hazy atmosphere. It's the only

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moon in our solar system with a substantial

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atmosphere, denser even than Earth.

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Avery: Um, and we've always known it's a weird place

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with its methane lakes and rivers. But now it

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seems the atmosphere itself is acting

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strangely.

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Anna: Researchers at the University of Bristol have

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uncovered that Titan's atmosphere doesn't

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rotate in step with its surface. The new

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discovery is that the entire atmospheric

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system seems to be tilted off axis,

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and it wobbles or oscillates almost

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like a spinning top or a gyroscope.

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Avery: The whole atmosphere is wobbling. How m is

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that possible?

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Anna: The prevailing theory is that some major

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event in Titan's past could have knocked the

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atmosphere off its original spin axis,

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causing it to wobble ever since. What's

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even stranger is that the size of this wobble

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actually changes with Titan's seasons.

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Avery: That has to be a critical piece of

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information for NASA's next big mission to

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the outer solar system.

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Anna: Absolutely. We're talking about the Dragonfly

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mission, the car sized drone like

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rotorcraft that's scheduled to arrive at

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titan in the2030s. Its whole

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mission is to fly through Titan's atmosphere.

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Avery: And if you're trying to land a multi billion

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dollar nuclear powered drone on a distant

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moon, you'd probably like to know if the

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entire atmosphere you're flying through is

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wobbling around.

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Anna: To put it mildly, yes. Understanding

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how the atmosphere behaves is absolutely

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crucial for calculating the landing

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trajectory. This discovery is a vital

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new piece of that puzzle.

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Avery: Okay, from the cold hazy reaches of the

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Saturn system, let's head sunward to a

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place that's anything but cold. Venus.

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And uh, for as long as I can remember, the

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defining feature of Venus has been its clouds

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of sulfuric acid.

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Anna: That has certainly been the dominant picture.

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But a new paper is challenging that in a

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fundamental way. A team of researchers

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decided to re, analyze, analyze data from

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NASA's Pioneer mission to Venus from the

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70s.

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Avery: I love these stories where old data reveals

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new secrets. What did they find?

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Anna: Pioneer analyzed aerosols in the clouds by

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seeing at what temperatures they burnt off.

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The researchers applied modern techniques to

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this old data and noticed massive spikes in

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water.

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Avery: So it's not a water cloud in the way we think

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of one on Earth, but water is a huge

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component of what it's making up the clouds.

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Anna: A, uh, huge component. It seems the water is

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locked up inside other minerals as

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hydrates. When they did the math, they found

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that this hydrated water made up the bulk of

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the aerosols, measured a, ah, staggering

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62%.

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Avery: This has enormous implications for one of the

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most exciting ideas in planetary science. The

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search for life in the clouds of Venus.

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Anna: It really does. One of the primary

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arguments against that possibility has always

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been the extreme lack of available water.

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But if water is actually far more abundant

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just chemically bound up, it completely

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changes the equation. It reopens the door to

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that possibility.

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And for our last story today, we're coming

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back to Earth. A new report has been released

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based on a survey of Australian opinions

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about space. And it reveals a really

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interesting picture.

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Avery: Let me guess, people love watching rocket

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launches but don't think about it much.

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Anna: Otherwise, that's a pretty good summary. The

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report shows a clear disconnect between the

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public's interest and their knowledge. People

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are three times more likely to want to

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increase spending on space, but awareness of

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what the sector actually does remains low.

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Avery: That's a key point. Things like using gps,

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checking the weather, or even making a credit

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card transaction often rely on data from

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satellites. It's this invisible

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infrastructure we take for granted.

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Anna: Precisely. The survey also found people

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want to see Australia pull its own weight and

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build its own space capabilities. And another

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point that came through very strongly was

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sustainability. Two thirds of respondents

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think it's important to invest in sustainable

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space practices.

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Avery: So the big takeaway is about communication.

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Anna: Exactly. The report concludes that there have

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to be real, tangible links made between this

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vital sector and the everyday lives of

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Australians, showing them how investments in

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space pay dividends right here on the ground.

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Avery: And that just about does it for us. Today we

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explored the life giving potential of, uh,

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Enceladus Ocean and the bizarre

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wobbling atmosphere of Titan.

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Anna: We rewrote the textbooks on the clouds of

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Venus and we took the pulse of public opinion

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on the importance of space right here on

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Earth.

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Avery: It's a constant reminder that there is always

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something new to discover. Thank you all so

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much for tuning in. I'm, uh, Avery. Thanks

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for.

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Anna: And I'm Anna. You've been listening to

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Astronomy Daily. For even more space

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and astronomy news, be sure to visit our

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website where we have a continuously updating

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newsfeed. You'll find us at

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astronomydaily IO. We'll

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be back tomorrow with all the latest news

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from our universe. Until then, keep looking

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up.