NASA Spacecraft Finds Storms On Jupiter

May 28, 2017
Originally published on May 28, 2017 1:44 pm
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LULU GARCIA-NAVARRO, HOST:

And this is Lulu's log - stardate May 28, 2017, where we consider matters of space, the stars, the universe and planets.

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GARCIA-NAVARRO: Big surprises from the biggest planet in the solar system. NASA's Juno spacecraft has been circling Jupiter for almost a year collecting data. The first results from the mission have finally arrived, and it's everything strange and wonderful - massive storms, electron beams and a really odd magnetic field. Jack Connerney joins me in the studio to tell me all about it. He's a NASA scientist and the deputy principal investigator of the Juno mission.

Thank you so much for coming in.

JACK CONNERNEY: Oh, thank you.

GARCIA-NAVARRO: Take us to Jupiter. What is it like?

CONNERNEY: It depends on where you stand. For many years, the Jupiter we're familiar with is the one you see from the equator. And that Jupiter's got red and white bands, and it's got this big storm - the Great Red Spot. It's got the white ovals floating by. But Juno, for the first time, took images of Jupiter from the poles. And when you look down from the poles, look down upon the poles, it's an entirely different image. It's almost - well, I wouldn't say almost - it is unrecognizable as Jupiter. And what you see are these cyclones, groups of cyclones, dancing around the poles, intricate storms.

GARCIA-NAVARRO: It used to be thought that if you were to land on Jupiter, you'd never hit a solid surface like the Earth has, that it's just sort of a big ball of gas. Now that you have all this new information, what do you think?

CONNERNEY: Well, Jupiter is still a big ball of gas rotating. But of course, much of that gas is under such intense temperature and pressure that you wouldn't recognize it as a gas. And if you were to fall into Jupiter, you would be crushed long before you got to anything that was substantially different from what we see on the surface.

GARCIA-NAVARRO: Why would I be crushed? What is driving that force?

CONNERNEY: So it's similar to when you're swimming, and you're diving. The weight of the water above you increases the pressure. Yeah, and so Jupiter, as you descend into the atmosphere, the weight of all the atmosphere above you just increases the pressure and increases the pressure and increases the pressure as you go further down.

GARCIA-NAVARRO: But let's say I was wearing some wonderful exoskeleton suit that would allow me not to be crushed, what would I see as I was falling through the atmosphere?

CONNERNEY: No matter what you wore, you would be crushed eventually.

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CONNERNEY: I'm sorry.

GARCIA-NAVARRO: OK, I'm going to be...

CONNERNEY: But - OK.

GARCIA-NAVARRO: ...No matter what. But let's say I was...

CONNERNEY: But for the sake of argument...

GARCIA-NAVARRO: For the sake of argument.

CONNERNEY: ...You'd enter the atmosphere. You'd pass the cloud decks. You'd pass the - an ammonia cloud deck. It looks like you may even see some ammonia snowflakes. You'd get deeper now into this mostly ball of hydrogen and helium. It would be getting darker. The pressure would be increasing. The temperature would be increasing.

Maybe down at about nine-tenths of the planet's radius you'd see enough electrical conductivity that you might be down at the region where the magnetic field is being generated. Not far below that, you would see, at about 2 million times the pressure on Earth, that the pressure's so great the electrons are squeezed off and the hydrogen becomes metallic. And then eventually, you get to the very center and that would be it.

GARCIA-NAVARRO: What is, for you, the most exciting thing that this has uncovered so far?

CONNERNEY: So I lead the magnetometer team. I'm interested in magnetic fields. And so one of the most exciting things, from my perspective, is that the magnetic field shows a tremendous amount of variation as we fly by on our trajectory. And so if you were to hold a compass, that compass needle would swing back and forth. So it's not quite as good a navigational tool on Jupiter as it would be on Earth.

GARCIA-NAVARRO: Can you tell me - why is it important to know more about Jupiter? Why is it important to you?

CONNERNEY: Why is it important to me? It's important to me for the same reason it's important to many of my colleagues - we're explorers, and this represents our frontier. At Jupiter, we're surprised in many, many different ways, and we overturn a lot of our long-held beliefs. But, you know, we, as scientists, don't bemoan overturning a long-held belief. We, instead, celebrate the success of a new understanding. And Juno's given us plenty to celebrate.

GARCIA-NAVARRO: Jack Connerney, deputy principal investigator on the Juno mission, thank you so much for coming in today.

CONNERNEY: Thank you, my pleasure. Transcript provided by NPR, Copyright NPR.