Science Matters with Lawrence Krauss

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Arizona State University physicist Lawrence Krauss discusses the latest science news, including new information revealing that water on earth may be older than the solar system itself.

Ted Simons: Thank you. ASU physicist Lawrence Krauss joins us each month to discuss the latest science news, which this month includes information that water on earth may be older than dirt. Here now is Lawrence Krauss.

Lawrence Krauss: Thank you. I appreciate it. We won't go into that.

Ted Simons: Water on earth is older than the sun?

Lawrence Krauss: Yeah, I have a prop here. Drink this -- that water has been around longer than the 4.5 billion years it took -- 4.55 billion years. It's amazing to think. I once wrote a book about it. I started saying my mother told me when I picked up water not to touch it you don't know where it's been. But a recent study has nailed this down you can -- the water on earth has a slight bit of a heavier isotope, heavy water, D20. There's one part in 100,000 or so to heavy water and all the water on earth, the oceans and everywhere else. It turns out that there's an excess of on earth and compared to the water that's produced at, say, room temperature or in the vicinity of the sun or in chemical processes in the earth or the solar system. It turns out that that excess is also found in comets, objects in the outer part of our solar system and the interstellar medium. You can calculate if you create that water at very, very low temperatures, bring together hydrogen and deuterium and oxygen, at very low temperatures it reacts more than the hydrogen. If the water forms between 10 and 20 degrees below absolute zero more or less, then you'll form this excess of deuterium. We have known there's this excess in the water on earth and comets. But the big quo was could you form it some other way, after the sun formed, could chemical reactions heated by the sun in region produce this? A team from the Carnegie institute, University of Michigan and other places did a comprehensive set of models and shows it can be produced by chemical reactions Suns the solar system has been formed, so the water must have formed at temperatures very few degrees above absolute zero. In the interstellar medium, the same processes that formed the comets and the outer part of the solar system. Those comets and other rocks that formed the earth contained the water which eventually bubbled up.

Ted Simons: So basically because the comets hit the earth forming water, which by the way is still difficult for me to comprehend -- a couple of rocks here and there --

Lawrence Krauss: 100 tons of material --

Ted Simons: They are not comets carrying water.

Lawrence Krauss: All the comets -- we could should there have been enough -- we have been around for a long time. 4.5 billion years. And there's been a long time, we can calculate given the comet bombardment there's been more than enough water delivered to earth by comets the rocks in the earth could have had water embedded in them too. We talked about it, a recent episode, there's probably a lot of water in the rock, in the earth mantle, may be enough to bubble up and form oceans. Those rocks were there from before the sun formed from dust particles combined together.

Ted Simons: Water was needed to form the sun, correct?

Lawrence Krauss: Hydrogen. No. No water was needed to form the sun. The sun is hot. You wouldn't have much water. Hydrogen. Hydrogen is the dominant stuff in the universe. Most of the universe is hydrogen. Most of the sun is hydrogen a big ball of hydrogen gas. But you have a little bit of oxygen and hydrogen and water can make oxygen.

Ted Simons: Where does water come from?

Lawrence Krauss: That's a good question. We're going to have an event -- a public event on water. Where water in the universe comes from, how you make habitable planets and questions like what about the water on earth? How did it affect life and how will it with salinity problems. We're going to cover everything from the beginning of the universe to water in April. But the bottom line, you can show there's a lot of water in the universe. Water is produced because hydrogen and oxygen are expels by stars when they explode and there's water everywhere. There's organic materials. So in fact the universe is replete with water. It's full of water and that's one of the reasons we're so optimistic that we might find life in the universe elsewhere.

Ted Simons: You're saying when planets explode --

Lawrence Krauss: Stars. All the stuff that sparse produce, hydrogen, oxygen, they interact in the exploding stuff coming out due to energy from starlight and other things and produce water.

Ted Simons: These stars don't necessarily like our particular stars don't need water to form themselves.

Lawrence Krauss: No. But our sun is relatively young. There have been stars going off -- 200 million stars have died in our galaxy before our sun formed spewing out material, producing heavy elements and producing the water we're now drinking. The water could have been produced by stars that exploded billions of years before the sun formed. It's amazing when you think about it.

Ted Simons: I thought that water was produced in France.

Lawrence Krauss: Not this water, I would hope. That would be awful for global warming.

Ted Simons: Speaking of global warming and human actions on the earth, what is the living planet index from the London zoological society?

Lawrence Krauss: It's an index that looks at 100 different species and tries to estimate how their population la changed over time. There are big questions about the complete statistical accuracy of that. They tried to improve their analysis. Every few years they come out with a report since 1970 on how wildlife species are doing. The last report is devastating. They claim 52% reduction since 1970 of 52% in wildlife species. Amphibians, mammals, reptiles, fish. 76% of fresh water species decline. Tigers, it's not a good time to be a tiger. Global population 1970, 100,000. Now 3,000.

Ted Simons: That's human activity?

Lawrence Krauss: Human activity. Not global warming, it's human intrusion. Human settlements, burning rain forests for agriculture, siphoning off water for human use. The biggest enemy of wildlife is human population. The best thing we can do in that regard is birth control. I was going to say something else.

Ted Simons: Well --

Lawrence Krauss: So these numbers are sobering but still facts, still figures. How do we know this?

Lawrence Krauss: When you do an exit poll in the elections, you're trying to do a reasonable statistical sample, you can't phone everybody but you can try to get a sample and hope it's valid. They try to sample certain populations and from those samples try to strap late. That's the question. There's no doubt that the 52% number is probably not worth -- not accurate at the level of a percent or two. But last time they got a 30% reduction. We're human. It's not a surprise. The human population is increased by a huge factor and humans displace animals. What's surprising is how severe it's been and it's unfortunate. The world will go on, but species in particular in the oceans and in fresh water, water is going to be the big issue. That's one of the reasons we're having this meeting. I should also say, another advertisement, is we're, next year, this 2015, for the origins project at ASU, is the year -- the human era. The first event is on extinction. We'll have a number of really interesting people talking about extinctions. Some people claim we're in one of the greatest extinctions of animals of all time, worse than when that comet destroyed the dinosaurs. It's human induced.

Ted Simons: Trees are being cut down before they can regrow --

Lawrence Krauss: Unsustainable. No big surprise that this is happening. It's just I guess the surprise, the reason I wanted to talk about the study suggest it's so great. We have to think about until the last 50 or 100 years the human imprint on this planet was not great. We were affecting things but like it or not whatever it's about global warming we're in a situation with the world's population over 7 billion using resources at an incredible rate that we're having a global footprint that's changing it in ways that it may never recover.

Ted Simons: So how do you do something about it? I mean you did your birth control. Really, what do you do about this?

Lawrence Krauss: I think we have to say, people are realizing this in the oceans, we have to ask about sustainable fishing. If we're interested in maintaining populations, many of them used for our own food, we have to worry about that. Should we be eating meat?

Ted Simons: Fish are dying off too. We can't eat trees.

Lawrence Krauss: The trees are dying off, a bad thing for global warming. In many places are sustainable if we do it right. I think we see. I grew up in Canada, on the east coast in Canada. Cod fishing ended there because they were decimated. Take means that in principle one can preserve those populations. It's not an easy problem and we have to decide, we may decide, you know, we don't want to change our life-style. I don't care if there are any more Tigers in the world or elephants. But we have to realize it's a choice. To me the only way -- we can't change things unless we know the facts. So I have often said as an educator the only tool you have is a hammer everything looks like a nail. For me, education is the way to do it.

Ted Simons: One more thing to talk about is something we talked about twice. Excitement then questions about ripples from the big bang. Then question marks. Now the whole thing looks like a big bust.

Lawrence Krauss: You're jumping to conclusions before you should. We think there's a signal of gravitational waves which were emitted at a billionth of a billionth of a second. After that people realize, there's we talked about it last time. If you want to go to the archives, that signal in principle is the most amazing picture ever produced by humans because it changes our picture of the universe. If right, the problem is that's a signal, that's light coming at us from a surface created when the universe was 300,000 years old traveled almost 14 billion years to get to us and gone through the galaxy to get to us. The galaxy has dust in it. It can be polarized and turns out in principle it can produce a similar signal. People looked up, away from the plane of our galaxy where they thought there would be no dust. A reasonable assumption. Since then it's been realized there's more dust than we thought and the study said, there may be enough dust to account for that but no one has actually looked at the area and that dust actually does account for it. What's really exciting to me is that the group that discovered this, and the group that found the dust, are working together on a new study to actually nail this question. I think the fact that science -- we want to be right because can there be anything more exciting than that? Yet one of the purposes of science is to prove yourself wrong. The scientific community including the people who made the original observation are now trying to see if we're wrong. We'll know in the next year. To me it will be really sad if it's not true. By no means do we know it's not true yet. I wrote a cover story in scientific American on this where I mentioned dust issue. It's still an open question. I think it's great testimony to the way science is done that the community can get together and we'll know the answer.

Ted Simons: It would seem to me a great focus of research would be on dust in the universe.

Lawrence Krauss: It's a huge source. Which we began the program with but first of all it's relevant to know about dust for learning about how water forms. It's relevant to know how stash formation, plan oat formation, and it's really relevant to know if we want to look through all that to see the beginning of time. We have to do a very good time finding out what's between us and them. I think it's wonderful that we're able to do that. We should be impressed. I'm still betting some of that signal is real. We'll see.

Ted Simons: It just seems to me, we only have about a minute left, no matter which way you look there's got to be dust out there.

Lawrence Krauss: Well, we live in a spiral galaxy. The plain. If you look up there's little galaxy between us and empty space.

Ted Simons: Is it truly empty space?

Lawrence Krauss: Definitely not enough to produce a signal. What's exciting about the satellite data that showed there was maybe enough dust in the region they looked at the entire sky. They actually had two spots where there doesn't seem to be much dust. so if this thing craps out we'll be able to exactly where to look next.

Ted Simons: We'll talk about it again I'm sure.

Lawrence Krauss: I'm sure we will. Good to see you again.

Ted Simons: Tuesday on "Arizona Horizon" we have another political debate sponsored by clean elections. We'll hear from the candidates running for Secretary of State. Secretary of state debate at 5:30 and 10:00 here on the next "Arizona Horizon."

That is it for now. I'm Ted Simons. Thank you so much for joining us. You have great evening.

Lawrence Krauss:Physicist, Arizona State University;

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