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NASA - NASA Phoenix Media Telecon - June 26
June 26, 2008
 

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Images for June 26 Media Telecon

Image 1 - Phoenix's Wet Chemistry Laboratory Units
Image 2 - Phoenix's Wet Chemistry Lab
Image 3 - Phoenix's Wet Chemistry Lab
Image 4 - Pan and Zoom of 'Rosy Red' Soil in Scoop
Image 5 - 'Rosy Red' Soil in Scoop
Image 6 - 'Rosy Red' Soil in Phoenix's Scoop
Image 7 -A Wet Chemistry Laboratory Cell
Image 8 - Delivery to the Wet Chemistry Laboratory



Beginning of recorded material

Jane Platt: Thank you very much. Hello, everybody. Welcome to a Phoenix Mars Lander media telecon for Thursday, June 26th. Sorry about the late start time, but there were several, actually many reporters who were still waiting to get on. Just a little housekeeping note for those of you who take part in these regularly, if you could call in about 10 or even 15 minutes in advance, that would really help us to start on time.

And, today, we have some really intriguing science results that we'll get to in just a moment when we switch to the scientists at the University of Arizona in Tucson. I do want to also let you know that we have Phoenix project manager, Barry Goldstein of JPL, here with us today. And, he'll be available to answer any engineering questions about the mission.

We do have visuals for today's briefing that are being posted right now at www.jpl.nasa.gov/news/phoenix/media.php. So most of them should be there now. And, then, they'll be up also at the other Web sites, which I will give you later on. We're going to switch right now to the scientists at the University of Arizona. And, Sara Hammond is going to introduce them. Sara?

Sara Hammond: Hello from Tucson, everyone. Let me tell you who our panelists are here today. We'll start with William Boynton. His surname is spelled B-O-Y-N-T-O-N. He's the co-investigator and lead scientist for the Thermal and Evolved Gas Analyzer from the University of Arizona.

Samuel Kounaves, K-O-U-N-A-V-E-F, the wet chemistry lab lead from Tufts University. Michael Hecht, H-E-C-H-T, the lead for the MECA instrument, the Microscopy, Electrochemistry and Connectivity Analyzer from the Jet Propulsion Laboratory. And, Leslie Tamppari, T-A-M-P-P-A-R-I, the Phoenix project scientist from the Jet Propulsion Laboratory. And, Bill, let's start with you.

Bill Boynton: Okay. Thank you, Sara. Well, TEGA has completed its analysis of the first sample that we received. We received this not quite two weeks ago. We successfully heated the sample up to 1,000 degrees Celsius. That's 1800 degrees Fahrenheit. And this is really the first time anybody's ever heated a part of a planet up to such high temperatures.

But we actually got some interesting results. We're very happy to report that the scientific data coming out of the instrument has just been spectacular. The instrument's working very well in that regard. What we found first of all, there was no ice in this particular sample. This is not surprising to us because this was a surface sample.

And, if you remember, it was actually sitting over the TEGA ovens for several days while we were working to get it through the screen to get it into the oven. We also found when we heated the sample that some small amounts of carbon dioxide were released from the surface of the grains at relatively low temperatures. Again, this is nothing that's too unexpected.

We know that carbon dioxide is very capable of sticking onto grain surfaces. So this was what we expected. what we did find when we heated the sample up to higher temperatures though, is we got small amounts of carbon dioxide released and also some modest amounts of water vapor. Again, this is what we were hoping to see expecting that the samples might have interacted with water and carbon dioxide in the past.

And indeed, we were successfully able to show that. At this point, it's rather difficult to quantify exactly how much was given off and to really do the mineral identifications. That's probably going to take several more weeks of analysis before we'll be really sure of what we're seeing.

What we can say now is that this soil clearly has interacted with water in the past. We don't know whether that interaction occurred in this particular area in the northern polar regions or whether it might have happened elsewhere and been blown up to this area as dust. So that's what I can say about TEGA at this point. And, now, I'll turn things back over to Sara.

Sara Hammond: Thanks, Bill. And, now, Samuel Kounaves is going to - oh, I'm sorry. Michael Hecht. My-my apologies. Mike is going to talk about the process of the analysis with MECA. Mike?

Michael Hecht: Thanks-thanks very much, Sara. What I'm going to try to do is set the stage, describe the experiment and then Samuel Kounaves who is a bona-fide, card-carrying chemist.

Samuel Kounaves: I'm a physicist.

Michael Hecht: I'm not configured to talk about the chemistry in my brain. He will describe the results for you. So I'd like to start actually by talking about a very memorable evening we spent last night celebrating the Mars northern summer solstice, which, by coincidence, fell just a few days after the Earth-Earth solstice.

And, we had a telephone hookup with some colleagues at the South Pole who one of us at least had-had met a few of them. So we had - we had a-a common link. And, we talked for about an hour sharing our stories of the north, near the north pole of Mars in perpetual sunlight while they-they talked about surviving the very, very long winter of the South Pole with no light whatsoever expect for the aurora.

And, toward the end of the teleconference, one of them, one of - one of the biologists described a greenhouse project that she was - she was monitoring that was designed to autonomously grow plants in a way that might be done on another planet, on the moon or on Mars.

And, I responded that I was very happy to tell her that, with the results that we had received from Phoenix yesterday, we could - we could begin to tell - to tell her exactly what-what aspects of the soil on Mars could support the growth of those plants, what nutrients were in the soil, what the critical parameters like pH are that would allow those plants to grow and what she would have to bring with her in the way of nutrients, in the way of fertilizer to allow that greenhouse to work on Mars. So it's a huge step forward.

And, of course, the reason we did that experiment is not entirely about growing plants. That's part of it. But it's also to ask what native Martian microbes might be able to live and survive and grow in that same soil. Also, the chemistry of-of soil dissolved in water. And, we know we have lots of water in Mars in the form of ice. The chemistry of that water of the soil dissolved in water can have a very large impact on geological features.

And, all we need to do is drive a bit north of here to the Grand Canyon to see an example of that. So this is the sort of thing we're after that we're trying to-to understand what is the chemistry of wet soil on Mars? What's dissolved in it? Any of you who've ever r - had an aquarium at home know that even something as simple as pH is the difference between-between a healthy and a deadly ecosystem.

So how do we do this? Well, you know, if you ever watch an after school teen movie made-for-T.V. movie, you always see a-a photo of a pic - a scene somewhere with-with students in smocks and goggles with no doubt the-the geeky science student matched up with the prom queen as they mix their beakers of brightly colored fluids and-and write out their lab reports.

We're essentially doing that. But if you think about the difficulty of going to another planet and mixing those beakers and stirring them and heating them and, you know, pipetting chemicals into them. It's extraordinary difficult - dif - it's an extraordinary difficult thing to do and one we've been working on developing for about 10 years.

The particular graphics I was going to speak to aren't on, and that's fine. I'll tell you basically the steps. The first step is to take the water, which we brought with us from Earth, that has been frozen solid in a block. Mel - heat it up, melt it and dispense into what we call the beaker. The beaker is this - is the bottom half of these chemistry cells. It's sort of the sleek, unadorned box. It's a flat box at the bottom that holds all the sensors in it.

So we can get the water into the cell by melting the ice and dispensing it. We then add a little, a little crucible into it, which allows us to calibrate it. That, that system was design - it was very similar to what you might use to dispense little pellets of candy. And, I'm not allowed to use brand names. But I think you all know what I'm referring to.

And we dispense a little-little cup of a calibration solution. And, then, we're ready to really make that Martian mud. So the rest of the mechanism up at the top is for introducing that Martian soil from a funnel into the beaker, mixing it up stirring it and allowing us to monitor all the sensors.

Now, we are seeing some very interesting things with respect to the soil itself some [shades] of some of the difficulties TEGA had with delivering this very clumpy soil. The delivery was entirely successful, but just we're-we're sort of interested to note that, in the end, once the delivery has been made, all of the soil is supposed to fall out of the funnel through a great big hole at the bottom. And, it's still spinning up there.

So there's - so just observing this process of delivering soil has also been very interesting. So at that point, I think you understand the experiment. We're making mud. We're stirring it up. We're measuring it with sensors. And, Dr. Kounaves will now tell all these very exciting things we've been finding.

Samuel Kounaves: Thank you, Mike. That was a brilliant description.

Michael Hecht: [Laughs]

Samuel Kounaves: Yes. We've had a very, very exciting day yesterday. We've, we've completed about 80 percent of the analysis on the first cell. This has been - this is the first wet chemical analysis on the Martian soil and any other planet besides Earth by our robotic lab assistant. It's been difficult and slow, but it performed flawlessly yesterday, and we were all very flabbergasted at the data we got back.

This is very preliminary data. But we took in - I presume we've taken in about a-a cubic centimeter of a soil sample. And we don't know the density yet and everything. But we-we appear to have gotten what we were looking to get. In general, we appear to have a variety of soluble species of ionic species of minerals or nutrients, whatever you want to call them.

Our biggest, it wasn't a surprise, I guess. We-we knew there was some level of acidity or alkalinity on Mars. But the first data indicates that the soil that we've sampled on the surface about an inch from the - from the - an in - the top inch of the surface material has a pH that would be in the alkaline re-region, somewhere probably between eight or - pH of eight or nine.

So it's a very alkaline soil where we've analyzed it. We've also seen levels, significant levels of a - of several other ionic species, soluble ionic species including magnesium, sodium, potassium chloride. And we still have-have not done the analysis for sulfate. That's coming up in the next couple of days.

There are some other species there probably. We have a lot of lab work to do and other ways to interpret this data. There are some hidden species in this set that we're still working on. We basically have found what appears to be the requirements, the nutrients to support life, whether past, present or f-future.

The sort of soil you have there is the type of soil you'd probably have in your backyard, v - you know, alkaline. You might be able to grow asparagus in it really well. [Laughter] But strawberries, probably not very well. And again, this is one more piece of evidence showing that these salts got there by some sort of liquid water action at some point in the history of Mars.

And so - and-and it's also surprising. This is very similar to the sort of analyses or analytical results we got from Antarctica dry valleys when we were down there very similar soils, very similar analyses. So all in all, it's very exciting for us. And we still have - I know there - have another part of the experiment to do and three more cells to go. And hopefully, we'll see even more. And, we'll have more results later.

Sara Hammond: Thanks, Sam. Now, we'll got to Leslie who's going to give - put this all into perspective for us from a scientific standpoint. Leslie?

Leslie Tamppari: Thank you, Sara. So as Sam and Bill just - and Mike just told you, we've gotten some good first samples to all of our experiments. This was always part of our plan, of course. The first - we've just accomplished our 31st Sol. And, as Mike mentioned, it's summer solstice on Mars. And that's about a third through our planned mission.

So, so far, you know, we've-we've been doing really well. We have two trenches in our area. We've gotten out first samples. We're going to continue digging in this area to the right of our workspace called Wonderland, which is in a polygon center. And we will proceed in the future to take subsequent samples to-to each of the three experiments, the TEGA, the MECA wet chemistry and the MECA optical microscope.

And, and then, hopefully, get down and take the sample of the icy layer. And, to date, in our first 30 Sols, we've not only accomplished these first samples. But we've also completed 55 percent of our true color panorama of the landing site. And we will continue to keep taking images. We have over 900 images in that panorama so far.

And, so we'll continue taking those and filling it out. We have a complete panorama of the entire landing site. And we have, of course, taken lots of atmospheric data. We take data almost every day. So we're learning a lot about the atmospheric science. Science is there.

We're studying clouds, water-ice clouds and dust in the atmosphere. We're studying the winds and the temperatures and also the pressures. We can look for the seasonal pressure changes as well storms and, perhaps, down to small-scale features such as dust devils as well. Let's see.

And, we've, of course because we have our two trenches, we have exposed hard layers in both. in the right of the work space as recorded a week or so ago, we did seem to dig up a few ice chunks that subsequently evaporated indicating that it's very much very probably ice material there. And we'll continue to monitor those trenches and-and look for changes as we proceed.

And, I think that's the summary that I wanted to give. So thank you very much. Sara.

Sara Hammond: Thanks, Leslie. Jane, we'll take it back to you for question.

Jane Platt: Okay. Thank you very much, Sara. And, thanks to our panelists today. We are ready for questions. So if you do have a question, please press *1, and we'll get you in the lineup. And, I do ask that everybody who'd like to get a chance, please, on the first round, please limit yourself to one question and one follow-up.

And to our speakers, please do identify yourselves, so reporters can follow along with the conversation and get the right quote attributed to the right person since we have multiple panelists today. Okay. We're going to go to our first question. And, that would be Emily Lakdawalla of the Planetary Society.

Emily Lakdawalla: Hi. I'm wondering if you, now that you've delivered one sample to the wet chemistry lab, if you can talk about what your thoughts are for where you plan on acquiring samples for the next three.

Samuel Kounaves: All right. This is Sam Kounaves. The decision of where to acquire the next samples will be a decision made by the science team at some point here. We've-we've, in the pr - in the past, assumed that we were probably going to do a gradient you know, dig further into the surface. It would be exciting to see what the material is like on top of the ice table. So that-that will be a decision to be made. But it will be obviously depending on a lot of factors.

Michael Hecht: [Yeah. I have something] to that. This is Mike. One of the things we have learned to do during the mission that we didn't expect to be able to do is to take a scoop of soil and deliver it to more than one instrument, the very same sample. And, in fact, this sample we just analyzed with the chemistry laboratory was also analyzed by the MECA microscope.

So part of that decision will be a concerted decision by the TEGA, w-with respect to TEGA, with respect to the different MECA instruments, to look at common samples with different techniques.

Emily Lakdawalla: Thanks. I'm wondering [also] if you could talk a little more about how the clumpiness of the soil manifested itself in its de - in your delivery.

Michael Hecht: This is Mike again. I probably didn't make that terribly clear. It w - the delivery went perfectly. It was simply observations about the fact that the soil did not behave as we expected in the course of-of the sequence of delivering it.

So it was - it was merely observation from images that it just - once you put it in a container, it stays there. You can pull the bottom out of the container, and it doesn't fall out. So we were fortunate that our design wasn't affected by that property.

Jane Platt: Okay. Our next question is from John Johnson from the Los Angeles Times.

John Johnson: Hi. Well, what-what does what you found so far say about habitability? That was the main-main goal of the mission. Can you be a little more specific about-about that?

Samuel Kounaves: This is Sam. well, you know, habitability in the last 10 years has become very broad. There are organisms on Earth that live in places we never expected them to live. So, you know, the-the-the extremities of-of the extreme boundaries are now very, very far out there. But what we did find, basically, is that the soil is - there's nothing about it that would preclude life.

In fact, it seems very friendly. Like I was saying earlier if you had it here on Earth, you could grow something in it very straightforward. It's-it's - there's nothing about it that's toxic to an average, ordinary plant here on Earth.

John Johnson: So I-I-I mean, does that conflict then with what Viking found when they - I think they used the term self-sterilizing environment?

Samuel Kounaves: Well, no. That's the-the very top layer may have components to it that destroy the organics. But that's because it's exposed to UV light over - you know, it could be over long periods of time. If the soil was placed in a - in a - in a protected area and it-it would behave differently.

I mean, we're not - we're not - we're talking about an exposed long-term environment versus a controlled, short-term environment or underground. Subterranean there could be, you know, microbes living meters and meters underground. They would be very happy. They wouldn't be exposed to this type of oxidant material.

Michael Hecht: May I add something to that? Again, this is Mike. To clarify the Viking experiments. Yes, w-w - all the evidence pointed to there being oxidants. But you could certainly sprinkle a spoonful of Viking soil over your breakfast cereal, and it wouldn't in the least bit upset your stomach. The-the ox - the oxidants are, you know, think of it as a very, very weak bleach solution.

They certainly wouldn't prevent things from growing. The significance on Mars is that if those - if organics build up very slowly from falling from the sky and particles of dust from meteorites, that very weak bleach solution, if you think of it that way, might be enough to destroy them as they come in and perhaps prevent life from every forming on the surface. But it's not - wasn't really suggest by the Viking folks that it would be enough to-to-to destroy existing microbes.

Jane Platt: Okay. We're going to take a question now from the Houston Chronicle, Mark Carreau. Mark.

Mark Carreau: Thank you. Thank you. My question might be somewhat similar. But it - first, I guess I'm looking for - from Dr. Kounaves some clarification. It - what you - what you've found is-is a nutrient material that would be friendly for life. And, I guess I'm going to ask you to sort of explain life of-of what kind of sophistication. But also, just to make sure, you - the-the nutrients are not organics? Or are they?

Samuel Kounaves: Okay. This is Sam. no. The-the - we were looking specifically at the minerals, the soluble, ionic species, the anions and cations that come from dissolving salts. So this is only - nutrients covers a broad range. This is a-a lower level of nutrients. You need the-the carbon, nitrogen, oxygen. But you also need other things, like calcium, potassium, sodium.

So w - so when we're speaking about nutrients and minerals, we're talking about things like that. And this is the type of soil that has those minerals in it. It has those cationic and anionic species it. So it-it would - it-it's very typical of the soils here on Earth minus the or-organics. And, uh- and that's-that's a different issue. That-that's not part of the ar - the analysis of the wet chemistry.

Mark Carreau: But what-what sorts of-of life, if you can even generally discuss, would-would benefit from these nutrients? Is this strictly a-a bacterial or viral or something more organized? you know -

Samuel Kounaves: Well again, these are only the inorganic materials. And on Earth there are a lot of chemotrophic bacteria that utilize inorganics. And, there are lots of plants that require these nutrients. So it's-it's very broad.

You know, it's a lot of-of varieties of life forms, microbial, plant life that requires certain nutrients and some sorts of Earth-type life would be happy to live in these soils. You know, but this, again, this is outside the question of the organics. We - that's-that's a separate issue.

Mark Carreau: Okay. I guess I was just wondering if you could give a few examples of the kind of life on Earth that would grow on - you mentioned a-an asparagus plant. [Laughter] I didn't know whether you were [being serious or not].

Samuel Kounaves: Yeah. Well, that's right. That's - I mean, I can't - there's prob - I mean, you know, asparagus and green beans and turnips love alkaline soils, you know.

Mark Carreau: [Yeah.]

Samuel Kounaves: But if you try to grow azaleas and blueberries, they love acidic soil or strawberries, so they wouldn't grow very well probably. So -

Mark Carreau: Thank you.

Samuel Kounaves: And, on the other hand, microbes grow everywhere. We find microbes in-in high pH's and low pH's and hot and cold. So they-they're a lot of microbes that are happy in a lot of type environments.

Mark Carreau: Thank you.

Jane Platt: Okay. We're going to go up to San Francisco now for a question from Dave Perlman at the San Francisco Chronicle.

Dave Perlman: Thanks a lot. And of course, I'm puzzled and-and am going to ask the same question in a different way. You mentioned the inorganic nutrients that might be there, that are there. But what inorganic substances are not there that you are - that are required for, to supporting life? If your asparagus and your green beans and your turnips is that all they need, those-those specific inorganic compounds? Uh -

Samuel Kounaves: [Crosstalk] This is Sam again. Well, the instrument we have there does not have the capability to analyze tho - every single type of inorganic nutrient. We analyze specific ones. And, from the ones we analyzed, they're there. There are lots of trace nutrients that organisms require -

Dave Perlman: Yeah.

Samuel Kounaves: at the trace levels. We-we aren't able to detect al - you know, a lot of trace nutrients. But we're assuming that, because a lot of the things that we expected to be there are there, a lot of the other trace nutrients may be there also.

Dave Perlman: Okay. So you're really r - you're really saying and you have said that-that there's nothing about that wouldn't support life. And, you've found nutrients necessary to support life. And, I recognize that the [extremophiles] do live on lots of this stuff too. But how does that increase the potential for habitability?

Samuel Kounaves: It increases it in terms of life as we know it to a broader range of organisms. So we found that it was you know, a-acidic like sulfuric acid and like Clorox bleach, it would take a really, really harsh, you know, the organism would have to be really special. This means that there's a broader range of organisms that are avail - you know, they could grow in this soil. Again, not on the surface.

The surface is highly UV bombarded. It-it might have a layer of oxidants. So subsurface, it you know, allows for the possibility of an environment very typical to - that you find on Earth in a lot of locations with a lot of types of organisms.

Dave Perlman: Okay. Thanks.

Jane Platt: Okay. The next question is at the New York Times, Ken Chang. Go ahead, Ken.

Ken Chang: Hi. I was wondering, what temperature was it that the water vapor was released? And, so what time period would this be that this water existed?

Bill Boynton: This-this is Bill Boynton talking. The water was released at high temperatures. We don't have a-a very quantitative number on that yet. The-the data is actually really pretty difficult to reduce from this instrument. It was somewhere along the high temperature ramp when we were heating it from 200 Celsius to 1,000 degrees Celsius.

Ken Chang: Okay. And, when might - when [I guess did] water exist?

Bill Boynton: I'm sorry. Say again.

Ken Chang: When was this water in liquid form? Can you constrain when this-this water was there?

Bill Boynton: No. This is Bill again. The-there really isn't any way we could say exactly where this water came from and when it interacted in the past with soil samples. That's really beyond the capabilities of the instrument at this time.

Jane Platt: Okay. The next question is from Richard Kerr at Science Magazine.

Richard Kerr: Thanks. I don't recall any mention of nitrogen or phosphorus in your list of nutrients at significant levels. Can you - you can measure that. Did - is there any sign of it? Or -

Samuel Kounaves: This is Sam. the phosphorus is probably not one we necessarily can see. I don't know if the mass spec will be able to see phosphorus. The nitrogen, we are - that's still in its - we're still looking at some of our sensors. We still have some data that we haven't analyzed. We can't make a definitive statement as to the - to the nitrogen yet. So we'll have a wait a few more days probably.

Richard Kerr: Thank you.

Jane Platt: Next, we go to Craig Covault of Aviation Week. Craig, are you there? It sounds like he might have accidentally pushed the wrong button. We'll come back to him if he gets back on. In the meantime, let's try Leo Enright of Irish Television.

Leo Enright: Thanks, Jane. I wonder if somebody could just save me a bit of reading up here to remind myself about debates about the pH of Mars soil. I know you say it-it's surprising, and you were careful to say that this was surprise - you seemed to put quotes around that, but it wasn't that surprising. But can you talk about whether the - how important this is in terms of previous debates about acidic Martian soil. And just give us some idea of the-the history of this discussion.

Michael Hecht: Well, let me be-be color commentator for a moment as-as I was before and then turn it over to-to-to Sam. This is Mike. One of our - one of our colleagues, Richard Quinn, has been looking at this question for about 15 years and has published on it back in the - or actually in the early '90s.

And, all I can tell you is that when-when, you know, he was standing there, and-and I believe it was Sam announced to him the pH value that we had measured this fellow jumped up and down as if he had read that number on a lottery ticket. It's-it's been something of-of enormous interest on which many, many models are built.

If I were writing the headline for this - for this day, I would call it Phoenix exclamation point with a little p and a big H. I'll turn it over to Sam. [Laughter]

Samuel Kounaves: This is Sam. well, it-it-it is, I mean, within the scientific community, there-there were a lot of hypothesis out there trying to-to deal with the environment in which the initial mineralogies were formed. And in order to look at them, the-the Rovers have come up some hypothesis as to the pH's in the - in those areas. And, of course, there can be very great differences.

We're - we have to remember we're looking at tiny areas on a planet whose surface area is equal to that of the Earth. And, so, you know, we have to be very careful that what we're trying to decipher here is-is we're putting words into a story. And, you know, we're only at a few sentences in a - in a book at this point in our history.

So yeah, the pH was, a lot of people had predicted acidic. A lot of people are-are saying - and-and basically, we're showing in-in this location, at this, on this sampling level that it appears to be an alkaline soil. That has some significances in terms of the-the mineralogy and other-other factors. .

But we'll wait and see what we find further down, for example. I mean, Antarctica, you dig down some places, and you find acidic soils right over the basic soil. So it's only a part of a story. We'll have to wait and see what the rest of the story [comes].

Michael Hecht: Mike again. And, I can add that even the interpretation of the Viking data that we were talking about earlier is dependent entirely on our assumption about the pH. And, you would have rewrite the Viking chapter of the story if the pH did not agree with-with what was speculated about at the time.

Jane Platt: Next question comes from Clara Moscowitz at SPACE.com.

Clara Moscowitz: Hi. I'm just wondering if you can clarify about the TEGA measurements. Is that the first time we've chemically measure that liquid definitely existed on Mars?

Bill Boynton: This Bill Boynton. No, we haven't done that yet with this instrument. I guess we-we know indirectly that liquid water has existed on Mars before just due to the erosion in the canyons and a variety of other observations that people have made.

At some point when we get ice in our samples and put them into one of the TEGA ovens, we will actually melt that ice and make our own liquid water in the small ovens. But at this point we haven't found any liquid water in the samples, not at these temperatures do we really expect any to be in the liquid form currently.

Clara Moscowitz: Okay.

Jane Platt: And, we have Craig Covault of Aviation Week back with us. Craig.

Craig Covault: Hi, thanks. Can you hear me this time okay?

Jane Platt: Yes, we can.

Craig Covault: All right. This is for Bill Boynton and perhaps Barry as well there are JPL. Yesterday's release discussed additional factors relative to the doors on TEGA. And, [crosstalk] I'd like you to take just a moment to discuss that a little bit and whether there's - I got the impression there was more than one door involved - possibly involved. It's the same kind of problem. And, if so, how will you manage to launch with that kind of latent situation with you?

Bill Boynton: Okay. Probably I-I should turn this over to Barry.

Barry Goldstein: Okay. Hi, Craig. How are you?

Craig Covault: [Crosstalk] Hi.

Barry Goldstein: Okay. Yeah, let me clarify this a little bit. We have been working - ever since the first door opening, we have been working to try to find out what the c - what the problem was. If you recall, the first cell that we opened had one side open perfectly, and the other side was hung up at approximately 30 degrees.

When we opened door number five, the next one, we noticed that-that the phenomena of one of the doors was actually on both of the doors on door number five. So recent investigation has shown that there's a mechanical interference that affects the inner doors of the TEGA. So if you think of the four cells on either side one door on each side of each of the end doors with be fine. The other doors will be hung up at approximately 30 degrees.

The good news about all that is that we have developed, by working in our test bed and putting the TEGA cells in a configuration that we see cell five in, we've developed a process that's been verified over and over again. And, we're very confident, based on these test results, that we'll be able to deliver samples through the-the opening in the door as it - as it sits on the planet right now.

Craig Covault: Okay. Thanks. [Crosstalk] And, a quick follow-up there was how did you come about actually launching with a situation like this that was not discovered on the ground?

Barry Goldstein: Craig, we're still looking into that. Our immediate - our immediate response when we have an anomaly like this is to try to find the root cause of what's happening, so we know how systemic or not systemic the problem is. And, then, we follow it up by the next step of seeing what we can do about it. And, we're already there. To work and determine lessons learned, which is what you're hitting at here, is the last step that we do. And, we haven't gotten that far at this point.

Jane Platt: Okay. Our next question is going to be from Ken [Cramer] of Spaceflight magazine. Ken?

Ken [Cramer]: Hi. Thank you. Well, fantastic results today. I guess my question also was about the-the pH of the soil. I mean, it's so unexpected, I guess, that it was pH eight and not pH one. I wonder if you could just go into that a little bit.

Samuel Kounaves: This is Sam. well, I - again, I-I'm not sure what I can say. We've - this is our first sample, our first data point. And again, it's somewhere between pH eight and nine. We haven't confirmed this. This is, a-a-again, preliminary data. We have other samples to run. It's - I - it's an interesting result. It's you know, it's unexpected for a lot people. It's expected for other people. So I-I'm not sure what else I can say.

Ken [Cramer]: Well, did-did you expect it to be pH one? I guess that's what I'm getting at.

Samuel Kounaves: No. I - personally?

Ken [Cramer]: Yes.

Samuel Kounaves: No. I - you know, I - in - over time, I've come to the conclusion that Mars - the amazing thing about Mars is not that it's an alien world but that it's actually very Earth-like in a lot of aspects. You know, chemistry and mineralogy is the same on Mars as it is on Earth. And, there will be places that may be acidic. There will be places that are basic.

And we found a place that has a, you know, alkaline covering on it. So I would have been surprised if it was pH one or pH 12. I am not surprised that it fits in the pattern that we see in the dry valleys in other places on Earth, you know, an alkaline or acidic soil.

Ken [Cramer]: Okay. Thank you.

Jane Platt: Now, we go to Rachel Courtland at New Scientist.

Rachel Courtland: Yeah. Hi. The previous results that we're suggesting on a different place on Mars that the place might be too salty to sustain life. And, I was wondering whether you have an - can get an overall measure from MECA as to the overall amount of salt in the soil.

Samuel Kounaves: We at this point, we don't have - we have preliminary numbers. We don't - this is Sam Kounaves. We-we-we don't have - in general at this point, we don't see extremely high salts. We haven't measured the sulfates yet. We-we actually were - one number that is-is surprising, I don't have - again, I don't have quantitative numbers at this point. But the calcium appears to be extremely low.

And the chloride appears to be low also. And from this, we have to wait for the rest of the analysis to see where the other anions are. But there-there were - -they were reasonable levels of salt. They were in the hundred parts per million to maybe thousand maybe at the highest levels. But again, we have to confirm these numbers. So it-it's in the right ball park.

Rachel Courtland: And, then just a follow-up, are you expecting these levels to change if you decide to dig lower down into lower levels?

Samuel Kounaves: They can change drastically. I mean, th - in the, in the - for example, in places in Ant-Antarctica where there's an ice table, the ice table - the horizon sometimes concentrates material. so we were - it's not uncommon to-to find levels in the hundreds of PPM's on-on the surface and-and go down 30 centimeters and find levels in the 15, 20, 30,000 PPM's. So - and vice - you know, so it-it can vary a lot depending on the movement of liquids, etcetera.

Rachel Courtland: Mm-hmmm.

Jane Platt: Okay. We're going to take a question now from Alicia Chang from Associated Press. But actually before we do take your question, I just remind folks. We have a couple of people left who have not asked a question yet. We're going to call on those. And, then, we'll take the second round. And, if you do have a-a question again, press *1 to get into the lineup. Okay. Alicia, without further ado, go ahead with your question.

Alicia Chang: Thanks. This question is for Sam. I just wanted to double check. The wet chemistry can't measure for organics. Is that correct?

Samuel Kounaves: No, the wet chemistry is totally an inorganic instrument.

Alicia Chang: Okay. And with your results today, I mean, the question of you know, whether this environment can support life, I mean, that's still an open question? Or -

Samuel Kounaves: Well [laughs] within the results that we have and that-that we're going to be getting again, life is very, very tenuous - not - it's very - it's-it's - gr-grows in places where you find extreme conditions. So there's nothing right now that we see that is extreme on-on - in this location.

Jane Platt: Okay. The next question comes from Bruce Moomaw at Astronomy Magazine.

Bruce Moomaw: Yeah. [Crosstalk] Yes. This is for Dr. B - this is for Dr. Boynton. On last night's release, there was a reference to some problems associated with the vibrating screen on oven number, that it might have set off a possible short circuit of some sort in "neighboring wiring." And, that as a result, you were going to be careful about using the screens on the other ovens. Could you give us any more details on that?

Bill Boynton: Yes. That is correct. But I think I'll pass that on to Barry to answer that question.

Jane Platt: Okay. Bruce, could you repeat that question for Barry?

Bruce Moomaw: Sure. l - in last night's press release, there was a reference to the fact that using the vibrating screen on oven number five to get the sample into TEGA - into that TEGA oven - and they had to vibrate it for a long time, as you know - set off what may have been an-an unspecified short circuit in some nearby wiring. As-as a result, they're going to have to be careful about how they use the vibrating screens on the remaining TEGA ovens. Could you give us any more details on that?

Barry Goldstein: You - you've actually got the essence of it there. What we found was when we opened the doors to cell number five, the current draw was indicating that we probably had a short circuit generated by heat. So that was theory that the team went on to investigate. And, we ran a diagnostic check on the vehicle that fairly certainly can confirm that.

However, that short - through that confirmation process, that short is actually in cell number four, which we've completed all operations on. So what we are doing now is we're being very deliberate and careful to not repeat that, to make sure that we don't have a similar occurrence happen in the future.

Bruce Moomaw: Okay. And, as a follow-up to Dr. Boyn - well, okay. First of all now, the-the - being careful about that, I presume, would mean that you would limit the total amount - the total period that you use the vibrator screens in the future, which might be easier to use now if you've got the sprinkle mode to make it easier to get the soil into the TEGA cells. Am I correct about that?

Barry Goldstein: That's absolutely correct.

Bruce Moomaw: Okay. And, secondly - and this is a scientific question for Dr. - [crosstalk]

Jane Platt: Okay. Can we can get back to you, Bruce -

Bruce Moomaw: Sure. That's [fine].

Jane Platt: Because we still have people who haven't asked their first question. Just put yourself back in the queue by pressing star 1.

Bruce Moomaw: Right.

Jane Platt: Okay. Thank you for that. Let's go to Mary O'Keefe from the La Canada Valley Sun.

Mary O'Keefe: Hi. How deep into the soil will you be digging? What-what's the-the deepest you think you'll be digging? [Crosstalk]

[Bill Boynton]: That's probably a Leslie question.

Leslie Tamppari: Okay. Yeah. Le - this is Leslie. We-we - our arm actually has quite a long reach. But what will be the deepest that we dig will be when we hit the hard ice table. And, we believe that in the Wonderland trench, that we've already encountered that that layer.

So it's about five centimeters or so deep. And we-we do have some thoughts in the future, after we've taken the samples that we need out at the Wonderland area, perhaps excavating in different areas to see if the depth varies at all. But that will [be] sometime far in the future.

Mary O'Keefe: Okay. Thank you.

Jane Platt: Okay. Let's take a question now from Emily Lakdawalla of the Planetary Society Web site.

Emily Lakdawalla: Hi. This is for Bill Boynton. The water vapor that was given off in your highest temperature run, would that be consistent with the water coming from bound water in minerals or even with hydroxyl groups] and phylosilicates or something. Is it part of a mineral structure? Or would it be actual water inside the soil?

Bill Boynton: No. It's actually, well, that's - your first suggestion is almost certainly the case. That associated, bound up in some minerals. It's not just surface absorbed water or any lightly bound water. At-at some point, we'll be able to identify or at least narrow down what types of minerals this might be. But it - at this point, all we can say is it's almost certainly some type of chemically bound water or hydroxyl.

Emily Lakdawalla: Thanks. And, I'm wondering if you can just talk about the strategy for delivering a sample to oven number five? Are you going to try to get it into the slit or maybe into that little triangular space at the top of the oven? [Crosstalk]

Male Voice: Go ahead, Bill. You can - you can - go ahead.

Bill Boynton: Okay. Yes. This is Bill again. We-we've done quite a few tests here in our payload test bed. And what we found in really every one of the tests that we did, by using this new sprinkle method, which I think you've probably heard about before where the Robotic Arm tilts just very slightly and runs its own internal vibrator to deliver very small amounts of soil in a sprinkle fashion.

If we sprinkle the soil just right above the opening between those two doors the soil flows very readily through that opening onto the screen. And, then, our own internal vibrator gets the soil through the screen very easily. On-on every one of the tests we ran we were successfully able to get soil through the screens. So we're-we're really pretty confident that we can do this.

And, another good aspect was it only took a few minutes. On screen number four, we ran that vibrator for nearly an hour in total over several days. We've tested it in the lab many times to 15 minutes. Here, we think we don't need to run it for any more than two or three minutes. So we're really pretty optimistic that those problems are behind us.

Emily Lakdawalla: Great. [Thank you].

Jane Platt: Okay. We're now in what I like to call bonus round. So if you do have a question and you've already asked one, you're welcome to press *1. And, we'll get you in the lineup. We will take the next question though from Mark Carreau of the Houston Chronicle.

Mark Carreau: Thank you. I think I want to circle back to almost the beginning when you sort of described the context for this particular wet chemistry experiment. And, I just want to make sure I understood correctly. This is the first time a probe has done anything of this sort of analysis on a - on a planetary body? Is that correct?

Samuel Kounaves: This is Sam. yes, when I said this is the first ever wet chemical analysis the Viking mission had a container of water they added to soil. They moistened the soil. But they were looking specifically to detect life. And, they were looking to detect the gases emitted by life. So that wasn't really a chemical analysis of a soil.

It was more in the process of trying to detect life, they accidentally did a slight chemical analysis. But it didn't really - so this is the first ever wet chemical analysis. This is a direct confirmation that all the sodium and chlorine and things like that we've before analyzed elementally with the Rovers and other instruments, that this is now direct confirmation that these are salts.

That they're soluble and that they're - they [come, for example, that it's sodium chloride probably. We know the-the identities. We haven't paired them up yet. But it's not something else, like you know, insoluble sodium or insoluble chlorine. So that-that - this is the first direct confirmation of soluble salts.

Mark Carreau: And-and the solubility of these materials is-is what makes them an n - th-this is part of what makes them a nutrient. They can be [crosstalk]

Samuel Kounaves: Absolutely.

Mark Carreau: Oh. Thank you.

Samuel Kounaves: Right. Absolutely. We need - we need to have soluble materials for - as-as nutrients. Minerals aren't useful if they're insoluble. At least most likely.

Jane Platt: Next we got to Ken [Cramer] of Spaceflight magazine.

Ken [Cramer]: Hi. Thank you. For Bill Boynton, just to follow up on the TEGA results are you definitely excluding organics? You did not find any organic material and any carbonates?

Bill Boynton: A-actually at this point, we can't really either include or exclude organics. We-we-we didn't see any signal that was clearly organic in nature. But at this particular time, the way we ran the analysis we weren't using our maximum sensitivity. So at-at this point, it's - we-we can't say, yes, we found them. Nor can we say they are not present. So we-we just haven't seen any conclusive evidence for them at this time.

But it's-it's really going to take a while before we'll be able to say anything about the organics. And, as I think you're aware, even if we do see them, we then have the problem of determining whether they are terrestrial organics that we brought along with us or whether they're Martian organics. And, we'll have to analyze our blank sample that we carried along with us in order to be able to answer that question.

Ken [Cramer]: Yes. What is the en - what is the lowest level? I-I read it's 0.2 percent for water. But what about the organics? What-what-what would be the lowest level there?

Bill Boynton: I can't say in terms of our the particular analysis we did the last time because we haven't quantified things yet. We're actually expecting to be able to do in the subparts per million level. Maybe in the 50 to 100 parts per billion level is what we ought to be able to see when we gear things directly towards analyzing for organics

Ken [Cramer]: Thank you.

Jane Platt: Okay. I'm going to give sort of a last call. If you do have a question before we wrap up, press *1, so we can get to you. We're going to call on - right now, we're going to go back to Bruce Moomaw. Bruce.

Bruce Moomaw: Yes. A couple of questions one for Dr. Boynton and one for Dr. Kounaves. First of all, for Dr. Boynton, did you see any emitted gases whatsoever from the TEGA heating other than water and carbon dioxide? Anything you've identified yet, that is?

Bill Boynton: There's nothing that we are certain of. There's you know, possibly some other gases given off. But the identification is a little ambiguous at this point. So the only ones we're conclusively able to say that we've seen are the water and carbon dioxide.

Bruce Moomaw: Okay. And, the second question is for Dr. Kounaves. There was some concern about Phoenix's r - rocket motors during its landing spraying ammonia on the land - on the surrounding landscape and over the soil samples. And, there was an ammonium ion sensor in the MECA wet chemistry s - sensor - system, which was designed largely to test for that. Have you seen any evidence of ammonium from any source in your first soil sample?

Samuel Kounaves: Okay. Yeah. This is Sam Kounaves. Yes, we did have an ammonium sensor in our setup. first of all, I should say though that the from the data from the Viking experiments done in the '70s it was noticed that the ammonia that was absorbed onto the material that they had tested basically escaped about 10 or 15 days.

So our experiment is beyond that point. The second thing is that, initially, at-at this point, our preliminary data does not show any levels of ammonium. So if there was any ammonia absorbed on the material, it-it-it-it's disappeared. And, it does not appear to have reacted with anything on the soil that shows high levels of ammonium. So, you know, this could change.

But at this point, we don't see any detectable amounts that would be attributed to ammonia. I should point out that our sensors are selective. They're not specific. And so what we need to do is, we need to do an analysis each we have a sensor array. And the sensors are capable of detecting several species. So they're-they're selective for a-a-a certain species and other species, they're less selective for.

So we need to do a very probably a complicated [with], you know, a chemometric analysis and look at the fingerprints and try to see if we can detect - it's sort of like - it's similar to a mass spec where you have patterns. And, you need to check the pattern. So at this initial point there doesn't appear to be any obvious ammonium contam - ammonium contamination that would be significant from the engines.

Bruce Moomaw: Okay. Thank you.

Jane Platt: We're going to go back to Leo Enright of Irish Television.

Leo Enright: Thanks, Jane. The-the - [do you] see a picture and an - and an animation called Rosy Red soil in scoop as part of the release today. Does somebody want to just briefly talk us through that that image, the-the perspective and so on?

Jane Platt: Sara, did you want - [crosstalk]

Michael Hecht: I-I can - this is Mike Hecht. First off, let me - wasn't blown up there. The front of the scoop has what we refer to as a divot. It's a little speed bump, if you will, that captures some of the soil as it pours out. And, using this divot, we can get extraordinarily high resolution images just from my robot arm camera. And, I believe the number is something like 20 microns per pixel.

For comparison, we have about four microns per pixel in the MECA microscope. So this is one of the techniques we use to get a-a quick, high resolution color image from soil we've just delivered. I can't say a great deal about those particular soil grains. It looks rather like, as it should, we-we delivered some of this same soil to the MECA microscope. And, that data was if it's not released, it's in the - it's-it's right on the break of being released.

It kind of looked rather similar. It's-it's different from the first soil delivery we had at the previous site. This-this particular delivery is from the center of one of our polygons where the soil, we believe, has been more processed, has been in that location for a much longer period of time. Whereas the material that we saw from our - from our original - from our original Baby Bear sample, was material that-that looked like it was more wind blown.

It was more varied. It was lighter in color, we believe. So this is the - this is the, you know, the-the red, the iron-bearing stuff that-that gives the-the local terrain its color. And, as you can see from the close up and from the animation, most of it is composed of aggregates, of very small particles of a size that really could be blown up - blown by the wind and-and eventually aggregate and form these little clumps and clusters.

Jane Platt: And, looks as though our last question comes from Emily Lakdawalla of the Planetary Society Web site. Emily?

Emily Lakdawalla: Hi. Two quick questions. One is, could you just, Bill Boynton, could you just explain the numbering scheme on the TEGA ovens. I would have thought that the second one you opened would have been number three if the one on the end was four. Can you tell me which numbers are which?

Bill Boynton: Okay. Certainly. I'd be glad to. our ovens are numbered zero through seven rather than one through eight, which is probably the reason you might have reasonable thought the one next to it would be three. Oven zero is directly opposite oven four. In other words, they are back to back with each other. And, the ovens on that north side are numbered zero, one, two, three in order. And, then, we go to the south side where the oven that we used first is number four. And, then, they go five, six, seven.

Emily Lakdawalla: Thank you. And, then one the MECA instrument, I noticed that there's a fair amount of dirt scattered over the deck. And, I'm wondering how you can prevent contamination of the cells just from the dirt that's dropped [from the] Robotic Arm?

Michael Hecht: This is Mike Hecht again. It's important to note, in contrast for example to TEGA, which takes in a sample that might be all of what? Is it 30 milligrams? The MECA cell takes a-a cubic centimeter of-of soil, which is a very large amount. It's the size of a - roughly a-a sugar cube.

And, so if we have little bits of dust that might line the sides of that funnel, that-that's going to be overwhelmed by the-the bulk of the material that gets delivered from the scoop and into the funnel. So we're not concerned about it. The mechanisms are protected, so that that soil won't-won't you know, impede the mechanisms from delivering it. So the short answer is that that's just - we just overwhelm it with a much larger quantity of material.

Barry Goldstein: Emily, this is Barry Goldstein. I'd like to add one thing to that. I'm familiar with the image you're referring to. A lot of the soil that is down low below the wet chemistry lab is actually runoff soil from the first delivery to TEGA where we had that very large delivery that ran off. So that is also part of what you're looking at.

Emily Lakdawalla: Thank you.

Jane Platt: Okay. And, that wraps up today's media telecon for the Phoenix Mars Lander. A couple of options, if you'd like to listen to a replay of the telecon, it will be archived online in a little while from now at www.nasa.gov/phoenix and also by phone for seven days on the replay lines, which are 1-866-485-0042 or, for international callers, that's 203-369-1614.

A couple of other Web sites, I'm told now all the images are up at www.jpl.nasa.gov/news/phoenix/media.php. And, also, of course, the University of Arizona Web site is phoenix.lpl.arizona.edu. And, as always, if you have any other Phoenix questions, feel free to call us here at JPL Media Relations, 818-354-5011 or Sara Hammond at the U of A, 520-626-1974. Thanks, everybody. Have a good day.

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