Science Matters with Lawrence Krauss

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Get updated on the latest science news like the Pluto flyby with Arizona State University physicist Lawrence Krauss.

TED SIMONS: Time now for our wildly popular monthly look at the latest science news with renowned physicist and best-selling science writer, here he is-- Lawrence Krauss.

LAWRENCE KRAUSS: Is that who it was?

TED SIMONS: Did you notice the wrinkle in time? Everything stopped, space and time stopped.

LAWRENCE KRAUSS: It's amazing how technology can sometimes do that. But you are always on.

TED SIMONS: I'm like a shark, I never stop moving.


TED SIMONS: Thanks for being here

LAWRENCE KRAUSS: Good to be here.

TED SIMONS: Good to have you here. It's good to have you here because Pluto has never had such attention.

LAWRENCE KRAUSS: Not since my daughter did her fourth grade project.

TED SIMONS: The fly-by of Pluto, talk to us about the fly-by.

LAWRENCE KRAUSS: It's just amazing. How can you not be amazed to think this little smaller than a car sized thing has been going for a decade on its own, traveling lonely without anyone to talk to except periodically sending a message back. There it is finally able to see what of course in my mind will always be the ninth planet, no matter what they say. Every time you open a new window on the universe you're surprised, and therefore it's not surprising we're discovering amazing things about that planet. Just think about it, I don't know if you were watching when they had the big celebration because of the pass-by, just almost 8,000 miles from the planet. But they knew it was 8,000 miles away, but assuming it hadn't died in the interim, it wasn't until 12 hours later that we knew it had done what it was supposed to do. Namely on its own it had turned, hadn't hit a meteorite or anything like that, taken pictures, waited and it can't do two things at once like many of us, then turned and sent things back to earth. It's almost, what, four or five hours for light to travel. So it's weird to think it was doing this stuff. And even if we wanted to, we wouldn't have known if it had been destroyed for less than about 12 hours.

TED SIMONS: Was 8,000 as close as it got?

LAWRENCE KRAUSS: 7,000, 8,000 miles. Within a day or so it had gone over a million miles past. It was a really literally fly-by, whoosh, fast. When you're going that fast it takes a lot of fuel to stop.

TED SIMONS: So what is this mission to designed to look at? What are we doing up there?

LAWRENCE KRAUSS: By the way, it almost never happened. It's amazing how many times it was almost canceled. And it was one of these things, almost like a good mystery story. There was only a small window of time when you could use -- Pluto was as close as it could be for a long time, for a hundred years probably. In order to get there you had to use Jupiter as a slingshot to speed it up, and Jupiter was in the right placement, the mission was almost canceled. It was designed originally to try and make it see Pluto. The best you could see from the Hubble Space Telescope was vague images. Now what's even neater by the way is that it's going out, Pluto now, which used to be a planet, now just one of the members of the Kuyper belt. Now it's going to, potentially, they are going try to interact with another smaller dwarf planet. What may be more interesting than Pluto, we may learn more from what's out there about the origins of the solar system, because that stuff has really not been processed. What's amazing about Pluto, I don't know if you have the pictures but it's been processed. That was the biggest surprise. There's the heart. There's the wonderful heart at the base of Pluto. When you get a close-up, I hope you have a close up of Pluto. There are no craters in a large part of it.

TED SIMONS: I read that. We can see formations and stuff but --

LAWRENCE KRAUSS: There are mountains. The crazy thing about the mountains are they may be 11,000 feet high but they have got to be made of water, because nitrogen and methane, also both frozen on the planet, don't have the tensile strength to form mountains. The only thing that can form a mountain that high is water. Earlier before we got there we didn't have any signs of water on Pluto. Those are ice mountains that are two miles high.

TED SIMONS: My goodness.

LAWRENCE KRAUSS: And around them, even in the bigger images, if you look at the plains, there's no craters. Big deal, there aren't many craters on earth. There's a flat plain, what's surprising when I looked at this, I'd just spent a month in a salt flats in Bolivia filming. There are very similar patterns on that, and they come from presumably stretching and compressing as the temperature changes. But we don't know what these are from, these ridges. From the plain that doesn't have craters on it.
TED SIMONS: So what's the deal with no craters?
LAWRENCE KRAUSS: The reason the earth doesn't have craters, the earth's crust moves around. First there's erosion from the winds but there are tectonics. The continents are going under continents. If you look at the moon has processed nothing in four and a half million years, is covered with craters. It's too cold out there to have any kind of heat mechanism, in addition, to cause that kind of global tectonics. Near a large gas giant, like the moons of Jupiter, those moons don't have craters because there are tidal forces constantly acting, bending and causing those surfaces to constantly re-form, but here is a cold mini-planet in the middle of nowhere and we don't know what power source can cause that surface to form. It doesn't have a huge atmosphere. The other thing that's really neat, it's got sort of a nitrogen atmosphere and it's losing 500 tons per hour of atmosphere. The atmosphere goes out to a thousand miles, it's losing that. That's fine, but how come after four and a half billion years it's still got atmosphere to lose? You tell me. These are wonderful mysteries.

TED SIMONS: Great mysteries. I read somewhere it looks like Pluto has a tail.

LAWRENCE KRAUSS: It has a tail, yeah. What's happening of course maybe that's not as surprising because there's a solar wind. You and I have actually talked about a solar wind the fact from the sun there are solar particles streaming out and the earth is protected from the solar wind by its magnetic field, but in fact Pluto isn't. So the solar wind bombards Pluto, and it actually strips off part of the atmosphere, nitrogen, strips it off and creates nitrogen ions, and they are carried by the solar wind. You have this atmosphere being bombarded by the solar wind and that produces a long tail of some 30, 40,000 miles at least behind Pluto. It's really from the solar wind bombarding the atmosphere and the planet, and stripping off nitrogen, making it ionized, and that's how we know it's there, it's ionized, and it goes out behind it. It's kind of a tail. It's really the fact that Pluto is unprotected from the sun.

TED SIMONS: Last question: You mentioned the Kuyper belt, it's kind of beyond the solar system out there where all these things go flying around. They have been flying around since the start of the solar system?

LAWRENCE KRAUSS: Well, a lot of them since the start of the solar system. What's interesting, some of the stuff out there may have been shot out the same way our little device was shot out, by Jupiter. By the gravity of Jupiter. It's like a vacuum cleaner, it ate up a lot of the stuff, why it's more massive than the earth. But it also it disturbed gravity shot a lot of stuff towards the sun or into the outer solar system. Lot of that stuff is primordial. We talked about the comet coming from that region, and that stuff largely has been unprocessed since the solar system began four and a half billion years ago. We have just sent a spacecraft out into that region and I can't imagine. It's wonderful what we're going to learn about the origin of our solar system.

TED SIMONS: It's fantastic, everyone's so excited. Every time we go by a planet it's fantastic.

LAWRENCE KRAUSS: This is the last one. You could say it's not because it's not a planet anymore, but it's romantic for many of us. I think perhaps it's the most surprising of all the planets we've gone by. I don't think anyone expected Pluto to look like this, craterless, ice mountains and those weird patterns. What are they caused from? Are they caused from erosion? Stretching and bending? Convection layers underneath? Looks like boiling oatmeal. If they are convection layers, where is the heat coming from? If you want oatmeal to boil you gotta have heat on it. This is, you know, billions of miles, three billion miles from the sun. Where on earth is the heat coming from?

TED SIMONS: We could talk about the pentaquark particle or save that for next time. Do you want to talk about the pentaquark, or do you want to talk about Pluto? How often do you have one of those?

LAWRENCE KRAUSS: Let's talk about the pentaquark. How often do we have a pentaquark?
TED SIMONS: It's been bothering me for a while.

LAWRENCE KRAUSS: The point is it's nice when we're surprised. About 50 years ago, a little over 50 years ago we first realized that protons were made of these particles called quarks, and protons are made of three quarks and others made of quarks and antiquarks. If you look at the model, it's possible to make a particle that might be stable that's made of not three quarks or a quark and an antiquark, but four quarks and an antiquark. That adds up to be a charge. It's a little complicated, it makes five. What's interesting is, for years people have been claiming to discover pent at apentaquarks and it's been proved wrong. About the day after we passed Pluto, the collider announced with really high statistics they have a peak of particles that looked like they must be pentaquarks, you could tell by the way they decayed. You could see a peak of this. What's interesting about this when you see something new in something that we think we understand, the strong force between quarks has been understood for a long time, but it's the basis of all nuclei. We're still trying to understand how those nuclei get built up. And we don't understand really what a pentaquark looks like. Is it three quarks here plus a quark and an antipentaquark there, or are they all mixed up together? Understanding the nature of that strong force will ultimately help us understand nuclear physics which will ultimately again help us understand nuclear reactions at the basis of our existence.

TED SIMONS: So quarks are the building blocks of the protons and neutrons we've got three -- everyone thought there were three, now --

LAWRENCE KRAUSS: We actually have six different kinds of quarks, by the way.

TED SIMONS: The three quarks -- three particles, whatever it is.

LAWRENCE KRAUSS: Called barions.

TED SIMONS: Now we got five. Does that mean it's a new matter? Have we discovered a new matter?

LAWRENCE KRAUSS: We have discovered a new, what you might call kind of fundamental particle. The quarks are really fundamental but it's -- we over the years, as we bombard things together, we discovered quarks come in unusual combinations. Protons and neutrons are the only ones. There are pions, kaons, mesons, but they all had the same kind of structure. This is a new type of elementary particle. The discovery said there were two types. All of that means we now have data. Data is a wonderful thing because now we can compare data to theory and figure some things out.

TED SIMONS: All thanks to the collider.

LAWRENCE KRAUSS: All thanks to the collider. I think still the best is yet to come. We're going to be talking about this for a long time.

TED SIMONS: Let's do it. Good to have you here.

LAWRENCE KRAUSS: It's great to be back.
TED SIMONS: And that is it for now, I'm Ted Simons. Thank you so much for joining us. You have a great evening.

Lawrence Krauss : Arizona State University Physicist

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