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Moderator: Greetings to everyone from the U.S.-European Media Hub in Brussels. I would like to welcome our participants dialing in from across Europe, Asia and the Middle East and thank all of you for joining this discussion.

Today we are very pleased to be joined from Vienna by Dr. Jim Green, Chief Scientist for NASA. Dr. Green will be discussing the search for life beyond Earth in the solar system, as well as NASA’s exploration campaign and the U.S. role in the UNISPACE +50 event taking place in Vienna June 18th to the 21st.

We thank Dr. Green for taking the time to speak with us today.

We will begin today’s call with opening remarks from Dr. Green, and then we will turn to your questions. We will try to get to as many as we can during the time that we have which is approximately 30 minutes. As a reminder, today’s call is on the record.

With that, I will turn it over to Dr. Green.

Dr. Green: Thank you very much.

What I’d like to do is give everyone a little background on what NASA’s been doing, primarily over the last ten years.

We’ve started an approach where we’re looking for life beyond Earth. We’re really trying to answer what we think is one of the fundamental questions that all humanity wants to know, and that is: are we alone?

The concept is, if we can find life in other regions, on different planets or moons, or even on planets around other stars, then life must be everywhere in the solar system.

Now, I’ll have to tell you right off the bat, we haven’t found life yet beyond Earth, but we’re making enormous progress in trying to understand where we would go to look for it, what are the signs that we need to look for, and what we are finding out.

About 15 years ago we asked our astrobiologists to define life. The reason why we did that is we wanted to build instruments launched on spacecraft to make those measurements that could give us definitive answers about life.

The result of that question coming back from the astrobiologists was actually pretty disappointing. The definition of life is one, it metabolizes; two, it reproduces; and three, it evolves. The reason why that’s disappointing is we’re not really able to build an instrument to make those three measurements that are the attributes of life as defined by our astrobiologists.

So we took a good look at the first aspect of that which is: life must metabolize. That means by taking in water and substance it can dissolve the material, extract energy, and the water then is used to extract the waste. So, water was a key element of, indeed, that definition of life.

So about ten years ago we started a process called “Follow the Water.” If we can go to locations in our solar system where water exists in liquid form, or existed in liquid form in its past, then perhaps life exists today or could have evolved and existed in the past.

So I’m now here to tell you what we’ve learned. We have, over the last ten years, made an enormous number of measurements and really completed what I would say is our first really good look at all the major objects in our solar system. With the completion of New Horizons fly-by of Pluto, we’ve looked at all the major planets, several of the dwarf planets, and many of the moons around these giant planets.

What we’re finding out from this data is that we can model what’s happened to these bodies over time. This turns out to be extremely important to do.

Venus, as we know it today, is uninhabitable. Its surface is hot enough to melt lead. Its pressure is enormous. Like going deep in the ocean you need huge infrastructures to be able to withstand the crushing pressures of the atmosphere of Venus.

Mars, on the other hand, is a much more arid, almost a desert-like planet with a very thin atmosphere.

But that’s what they are today. What we have found out by the observations that we have made is that both Venus, Mars and Earth in its pasts were all blue planets. Were all ocean worlds. Were all more Earth-like in its past than ever before.

It seems now that Venus was probably our first habitable planet in the solar system with a significant amount of water on its surface. And over about the last 800 million years it went through an enormous run-away greenhouse effect to create the planet as we know it today. Could life have existed on Venus in the past? It certainly appears that it has all the attributes, both from the size of the planet, the kind of materials that are on it, the oceans that we expected to have on it. But currently it has evolved very differently.

Likewise Mars, two-thirds of its northern hemisphere was under water. In fact, some places more than a mile deep. Mars, indeed, had climate systems — rain, clouds, ice caps, and huge oceans for a significant period of time. But it underwent rapid climate change early on in its history. It was a blue planet for perhaps as much as 800 million years — long enough to have started life on that planet too.

We’re now coming to the realization that what’s happened on Venus could happen on Earth. What’s happened on Mars could happen on Earth. And that we need to understand these planets in their own right in addition to teasing out an understanding of whether they could have harbored life in the past or perhaps harbor life today.

We’re also finding out another startling part of our solar system could also have habitable worlds, and this is beyond the orbit of Mars. These giant planets have moons, and these moons we believed for long periods of time were more icy bodies, frozen if you will, and without liquid water we don’t anticipate life to have occurred or lived. But now we’re finding out that many of these moons are actually ocean worlds with an icy crust. We see the moon Europa, which is a moon of Jupiter, and that moon, underneath its icy crust, we now believe the ocean is probably twice the volume of water than we have here currently on Earth, and yet that moon of Jupiter is about the size of our own moon around Earth.

We’re also finding out as we move even further out in the solar system that Saturn has a number of icy worlds, ocean worlds, if you will, today is what we would call them, because underneath their ice crusts we believe there is a significant amount of oceans and water.

For instance, Enceladus demonstrates this water connection by cracks where water vents from these cracks, pouring out of the moon at all times of the day and all points in its orbit. It actually creates an entirely new ring around Saturn called the E-Ring, made up of icy particles.

Another moon is very fascinating at Saturn and it is the moon Titan. Titan is about the size, actually it’s larger than the planet Mercury. It has its own atmosphere which is mostly nitrogen, and it is the only other body besides Earth in the solar system with liquid on its surface. But the liquid is not water, it’s methane. And in fact, some of these methane lakes are bigger than our own Black Sea.

On Titan there’s what we would call a hydrological cycle, except not of water, of methane, where the oceans are evaporating, that vapor is being transported, and it’s currently raining – in the southern hemisphere of Titan- methane, creating new seas as we know it today.

One of the reasons why Titan is extremely important to look at is if there was ever a place to look for life not like us, it would be Titan since the liquid that would be involved in the metabolism process wouldn’t be water, but could be liquid methane.

So these are really exciting places and we’ve learned an enormous amount by them. We have future missions going to Mars. We’re thinking about how to go to Venus and interrogate whether it maintains life today. We have missions, we’re planning to go to Europa. We have missions, we’re thinking about going back to Titan and the Saturn system. And these are all making enormous progress as we move forward.

Now in addition to that, humans play a role in studying the solar system. Right now we are moving forward with the concept of going from low Earth orbit into what we call cislunar space. This is an area around the moon where we can interrogate and we can learn to live and work on a planetary surface, and that first surface will be the moon. And that will be done before we eventually go to Mars.

All these are really exciting times for our space program. We’re working very hard to continue to make enormous progress. We have tremendous support from the American people, the administration and congress as we move forward.

I think with that, let me open it up for questions.

Moderator: Thank you very much for those remarks. We will now begin the question and answer portion of today’s call.

Our first question comes to us from Mohamed Ataya, calling in from Egypt.

Question: I’m Mohamed Atay from Baladna El-Youm

newspaper. I want to ask about is there any kind of life on Mars after discovering the organic materials on the planet?

Dr. Green: A really good question. Thank you.

The most recent set of observations that Curiosity made at Mars are tremendously exciting. What Curiosity discovered is there are complex carbon molecules. In many ways these molecules could have been created by life. They may actually have been created naturally. We don’t know, but we are continuing to do that research.

Accompanying those measurements were also measurements by Curiosity of methane that’s leaking through the surface of the planet. Now this is tremendously exciting because 95 percent of all the methane here on Earth is created by biology, by life. From microbes to termites to cows to humans. So although methane can be generated abiotically, in other words not by life, it’s tantalizing to think that there may be life underneath the surface of Mars.

What we’re finding out here on Earth when we study the amount of biomass on Earth that relates to this topic goes like this: Our astrobiologists have gone deep in the Earth and have gone to far-away places which are very extreme here on Earth in temperature and dryness, and everywhere they go and find water, they find life. In fact the current estimate is there’s more biomass below our feet than there is walking on the surface of this Earth, or plants. This tells us that when there are extreme environments, life moves into the rocks. Therefore, there may indeed be life on Mars today, but it’s below the surface.

Moderator: Thank you.

For our next question we’ll turn to a question submitted in advance by Nenad Jaric Dauenhauer, the science editor for Index Magazine in Croatia. Science by the Pew Research Center shows that an overwhelming chunk of Americans appreciate the importance of space exploration. NASA has a vast portfolio of different missions, but when rating nine of them most Americans say they are most interested in missions closer to Earth and say monitoring the climate system and monitoring asteroids and other near-Earth objects for potential collision should be top priority.

Is the interest in deep space and aliens waning in the United States? Can you please comment?

Dr. Green: As I touched on very briefly, and this was a very important study, the Pew Research does a very good job of obtaining their study conclusions. What we’re finding out is the study of planets and their habitability is important to the Earth. It’s as important to the evolution of the Earth as the evolution of our climate.

As I mentioned, Venus, only about 700 million years ago, started with a runaway greenhouse effect and now it’s completely uninhabitable. So we want to understand what triggered that. What were the elements on Venus that allowed that to occur?

What’s happening on Mars is also relevant. Currently Mars has no magnetic field, and the solar wind has been stripping away its atmosphere. In fact most of the evaporated oceans on Mars ends up going out the atmosphere and into the solar wind as evaporated gases become swept away, never to return. We believe that’s primarily because Mars lost its magnetic fields and lost its protection.

As we study the Earth and we know the climate is changing, the planetary scientists I can tell you that the climate on Earth has done nothing but change and we think it’s not about the change, it’s about the rate of change and what the contributing factors are that make that up.

When we look at the Earth’s magnetic field we see the tendencies of the field to start the process of flipping. We know the Earth’s field has flipped many times in its past. We don’t know exactly how or why that occurs. We know the flip of the field, when that occurs, the magnetic field of the Earth virtually goes to zero as what we believe are currents deep inside the core are rolling over the poles and starting to move in the opposite direction creating the new field.

So there will be a time when the Earth’s magnetic field will have dissipated and will look like Mars, and therefore we will be susceptible to solar wind stripping also.

So what we’re learning at Mars is important for Earth and what we’re learning at Venus is also important for Earth. These are giving us new and important perspectives that we must continue on. I think that fits really well with the public’s desire to be able to study the Earth and its changes.

Moderator: Thank you.

For our next question we will turn to Peter Morvay who is calling in from Hetek Magazine in Hungary.

Question: Good morning, Dr. Green. My question concerns another exciting aspect of our solar system. According to recent report by Goldman Sachs, private companies are looking forward to enter the new asteroid gold rush. What does NASA think about this? Do you plan to enter this race? Is it financially reasonable and legally possible? Thank you.

Dr. Green: Let me see if I can rephrase your question. There’s a variety of companies in the United States that are moving commercially into space, and how does NASA interact with them?

Question: Yes, exactly.

Dr. Green: All right. We are very delighted by companies in the United States taking on the challenges but also the benefits of moving off this planet and developing capabilities that can be leveraged in many different ways, allowing NASA to, indeed, purchase those services and therefore spend additional money that we have instead of maintaining our own infrastructure, but indeed exploring other areas. Going to the moon and then on to Mars.

So this is a really exciting time where the commercial entities are now coming about and we’re working with them I think very well. We have, I’ll just give you one example, SpaceX. SpaceX is quite interested in continuing to explore the solar system, supporting delivery of materials and eventually humans to space stations, but also going to Mars. And we’re in discussions with them, and we have Space Act Agreements which is the right connection that we need to make.

So once again, this is a really exciting time and NASA’s planning to take full advantage of these companies.

Moderator: Thank you very much.

For our next question we’ll turn to a pre-submitted question from Sandzhar Khamidov from VOA Russia. What is your assessment of President Trump’s announcement on Monday about the DoD and Pentagon establishing a Space Force, a Space Force as a 6th branch of the armed forces in order to have dominance in space?

Dr. Green: NASA as a civil space agency has always interacted with our Department of Defense, and that interaction will continue no matter how the Department of Defense organizes itself.

So I think from that perspective, NASA will continue to work in that venue and provide information and services that the Department of Defense may need.

Moderator: Thank you.

Our next question comes to us from Guido Lafranchi calling in from the Diplomat Magazine.

Question: Dr. Green, thank you very much for your updates.

My question would be on the budget of NASA. So the budget measures have a share of the federal budget, of the overall U.S. budget. It’s at a historic low in the last few years, absorbing only 0.5 percent of the federal budget, down from way higher figures in the past.

So how do you plan, if you plan to try to reverse such trend and convince politicians and the Americans in general to invest more in space science? Thank you.

Dr. Green: I think you’re pointing out how the NASA budget has changed by looking at how NASA invested, or how the country invested in NASA in the ‘60s, in the big push to go to the moon.

Of course you must recognize that in the ‘60s NASA as a beginning agency had no capabilities, no facilities, and in fact was just beginning to develop the rocketry necessary. So significant investments were made by the United States to gain those technologies.

What’s been happening since then is indeed, now that we have an infrastructure, NASA’s been using it. Consequently its budgets in terms of its share with the gross national product has gone down from the ‘60s. But in reality, the administration is very supportive of NASA’s activities and is proposing to Congress approximately a $20 billion budget — the highest budget in more than ten years of NASA activity. Congress has over the last several years not only taken that but even added additional funding.

So I think from a NASA perspective, we are really doing quite well. We’re making enormous discoveries. We’re leveraging the initial investment that the country has made in the space program. And I think our future is very bright.

Moderator: Thank you.

For our next question we’ll turn to Marlowe Hood calling in from AFP.

Question: Hi, Dr. Green. Thank you so much for making yourself available for these questions.

You noted in reference to runaway climate change, you said we now realize that what happened on Venus and Mars could happen on Earth, which leads me to ask, NASA has always been at the forefront of the space-based research on anthropogenic climate change, and I just wonder if you can tell us whether that remains as much of a priority today as it has in the past.

And a very narrow question about what you mentioned on the complex carbon molecules that Curiosity discovered. Is it possible that there could be some kind of signature in those carbon molecules that would allow you to definitively say that their origins were either life-based or occurred naturally?

Dr. Green: Let me piece part your first question. Indeed, NASA’s Earth Science Program is incredibly healthy and we’ll continue to monitor and make exceptionally important observations of the Earth, the Earth’s climate and its oceans and the hydrological cycle and many other aspects of the Earth so important to study and provide that information to our policy-makers in terms of what they will do next with that info.

The second part of your question, the complex organic molecules that are found by Curiosity really helps support the major next step that NASA’s taking, and that is for us to be able to determine if life actually created those we need to bring them back into the laboratory here on Earth.

So NASA’s developing a mission currently we call Mars 2020. It’s a Rover that will core rock and create a series of samples that by the end of the next decade we’re planning to bring back to Earth and study them here. With the laboratories that we’ve developed and the capabilities that we have today, far exceeding anything we can put on a Rover, bringing the samples back are the next best way to determine if Mars had life in its past and perhaps has life today.

Moderator: Thank you. We’ll again turn to a pre-submitted question from Simone Valesini from Galileo Gironale di Scienza in Italy. They ask: Aside from the most promising targets like Europa and Mars, are there other planets or planetoids in our solar system that hold promise of hiding extraterrestrial life forms? Do you have plans for the exploration of these locations?

Dr. Green: Great question. There are many places we haven’t been that are incredibly tantalizing. You know, the giant plants Uranus and Neptune, we really haven’t had orbiters in those areas for long periods of time that will enable us to study those, but we think there’s probably ocean worlds there.

Triton, for instance, a huge moon of Neptune, which is actually bigger than Pluto, we believe is a captured Kuiper Belt Object much like Pluto in many ways, and may have an under-ice crust ocean. And we think Pluto does too, now.

So indeed, the more we look at the outer part of our solar system, the more we recognize that water in liquid form may be an integral part of many of these satellites and therefore may actually have opportunities to harbor life.

Moderator: Thank you.

For our next question we will turn to Andras Toth from 444 in Hungary.

Question: Thank you.

Dr. Green, how will NASA’s upcoming mission Europa Clipper improve our understanding of Jupiter’s moon, Europa and how to determine if it’s habitable? Thank you.

Dr. Green: Clipper is being built today. It has an array of instruments on it which are incredibly sophisticated and more powerful than Cassini had. Our plans are to really use its ice penetrating radar to look at the thickness of that icy crust with multiple fly-bys that we will make as the spacecraft orbits Jupiter and then rendezvous with Europa, its moon.

Now the ice crust, we believe, will be very thin in some places. Thin enough that perhaps it will have cracks where geysers are also emanating. It turns out, recent observations by Hubble does indicate that Europa, a huge moon about the size of our own moon, has indeed geysers of water pouring out, sloshing onto the surface and resurfacing the moon itself.

In addition, as the cracks open up it also pushes ice sheets underneath other ice sheets. This is analogous to plate tectonics here on Earth which allows the circulation of materials so necessary for life to be able to grow and provide food and other elements.

So our plan is to find the plumes, fly through the plumes, look for places to put down landers, and eventually fall into a crack and get into the ocean of Europa.

Moderator: Thank you.

We will now turn to Insaf Basirov from Rossiya Segodnya Media Group.

Question: Good morning, Mr. Green. I have two questions but I’m not sure if you’re the correct person to direct them to. But anyway, so there is a project, Lunar Orbital Platform Gateway, which is scheduled to be future cooperation area for Russia and the USA. So the question is, which stage right now this project is, and do you plan to invite Russian scientists to work on this project? And in which areas? So what their work would be.

And a second question is, does NASA have plans to invite Russian astronauts for the first test pilots on the space shuttle Orion after the completion of this project?

Dr. Green: Thank you for your questions. Indeed, the Gateway is one of the critical elements of NASA’s human exploration program that will allow us to live in space and work in space untethered by low Earth orbit.

Now that particular capability has advanced engines that will allow many activities that we would do on the surface of the moon to be tele-operated by astronauts in the Gateway. That will enable us to practice what we would do on Mars.

Currently the Gateway is being discussed in many ways internationally. Many countries are expressing interest to be involved in the Gateway, in different parts and aspects of it. No announcements have been made yet as to what agencies will do what, but I think you’ll rapidly see over the next year many of these questions that you ask will be definitively answered.

Moderator: We’ll now turn to a question submitted in advance by Ioanna Iliadi from Armyvoice in Greece.

Question: What is the current framework of cooperation with the European Space Agency on transponders of outer space information through satellites?

Dr. Green: Let me mention that ESA and NASA have had a very long cooperation in the area of radio transmissions. As an example, that cooperation allows the use of ESA dishes for tracking NASA satellites, and NASA dishes here on Earth for tracking ESA satellites. So this quid pro quo arrangement has been going on for several decades. It’s an outstanding way to share capabilities and facilities. And we really appreciate ESA’s ability to work with us in this manner.

The bottom line is, this kind of cooperation really enhances both our space programs. In fact, these capabilities now that we’ve developed them in commonality allow one agency to help another agency during spacecraft emergencies.

I think this kind of international cooperation is definitely going to continue and it’s really had many examples of cooperation which we indeed really appreciate [with] this approach. So I think it’s going to continue.

Moderator: Thank you. Unfortunately, that was the last question we have time for.

Dr. Green, do you have any closing words you would like to offer?

Dr. Green: I really appreciate the opportunity to tell you some of the new and exciting things that we’ve discovered. These things are not going to appear in textbooks for perhaps many years yet, and yet we’re making so many new and rapid advances, it’s really a wonderful opportunity for me to get some of these words out on what we’re doing and allow you to ask me questions for more detail.

So thank you very much for your time.

Moderator: And I want to thank you, Dr. Green, for joining us. I feel like we could have kept you here all day with questions. I’d also like to thank all of our journalists for participating and for your questions.

U.S. Department of State

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