SGU Episode 149
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|SGU Episode 149|
|May 28th 2008|
|SGU 148||SGU 150|
|S: Steven Novella|
|R: Rebecca Watson|
|B: Bob Novella|
|J: Jay Novella|
|E: Evan Bernstein|
|D: Diana Blaney|
|Quote of the Week|
|The high-minded man must care more for the truth than for what people think.|
- 1 Introduction
- 2 News Items ()
- 3 Questions and E-mails ()
- 4 Interview with Diana Blaney (39:37)
- 5 Science or Fiction (1:00:20)
- 6 Quote of the Week ()
- 7 References
You're listening to the Skeptics' Guide to the Universe, your escape to reality.
News Items ()
Ban Wi-Fi ()
New Zealand Considering CAM ()
UK CoS Free Speech Follow up ()
Science Reporting ()
Questions and E-mails ()
Tasmania Correction ()
I've heard both Steve and Rebecca make this mistake now (Steve on the podcast a couple of times, and Rebecca in a blog entry).
Tasmania is not in New Zealand! It's an Australian state, the small island down the bottom.
So far you've attributed both the world's oldest tree (or shrub, whatever it turned out to be) and the Tasmanian devil to New Zealand. Not fair! :)
Anyway, love the show and keep up the good work.
Love the podcast.
Just wanted to write in about a minor error in your last podcast about the thylacine. You said in your segment that it went extinct in 1933. In fact it went extinct in the wild in 1933 and the last thylacine died in captivity in 1936.
Sorry to nit pick but I had to write in. :P
Least Skeptical ()
Hi. I have listened to all the shows and I have a question.
At heart I am a skeptic and I think, probably, that the vast majority of educated people are also privately of the same inclination. Your show gives a voice to a huge silent majority that cant be bothered to speak out or confront the status quo because its just too much like hard work and will attract unwanted passionate debate, specially so on the bigger topics. If your out there doing it on podcast then I dont need to as the voice of sanity is present somewhere, so thanks.
I am torn, however, because if I am really honest about it, one key reason that I listen to your show is in the hope that Bigfoot rides into your studio on a unicorn and hijacks the microphone to announce the second coming of Elvis. Go bigfoot.
My question therefore is, what are you least skeptical about. If you had to list all the things that you were skeptical about 100% what would be the last thing on the list. Mine, for instance, is telepathy. I think there might be scientific possibilities there even after you consider the evolutionary implications. Anyway I must go, my wife is just about to shout up the stairs about the mess I left in the kitchen (QED).
Interview with Diana Blaney (39:37)
- Dr. Blaney is a soil scientist involved with the Phoenix Mars lander.
S: Joining us now is Diana Blaney. Diana, welcome to The Skeptic's Guide.
D: Oh, I'm glad to be here.
S: And Diana is a co-investigator for soil science and geological studies of the Jet Propulsion Laboratory. And she is involved in the recent Phoenix mission to Mars. So, Diana, why don't you first just give us an update on the Phoenix mission; what's it all about? And how's it doing?
D: Well, it's a mission to the martian arctic. We've landed in a place which is filled with landforms that have been basically shaped by ground ice in the area. And what we're trying to do is understand how the ice may have acted as a place to preserve soil chemistry and other materials; and then also understand how ice and weather moves around and affects the arctic.
Mars, like the Earth, has a pretty big polar cap, but unlike the Earth, it's sometimes made out of CO2 ice in the winter time. And it moves, and basically controls the entire atmosphere and climate of Mars to some degree. So, we're here both setting the soil chemistry, which is kind of what I'm interested in, looking for signs of habitability. Is there any evidence of liquid water having melted? And really trying to get to understand how the ground ice got there, and how it's interacted.
The ice has the potential to perhaps preserve organics that may be there on Mars. But, it's gonna take us a while to get down into the dirt, and really understand what's going on there.
S: Okay. And just for the background, the lander, the Phoenix lander landed on May 25th, right? We're now recording this on May 28th. It's only really been there for a couple of days.
S: How did the landing go?
D: The landing was wonderful. It went picture perfect. I mean, I don't think anyone could have expected it to be any better than it did. I mean, we got back, we were doing things, practicing what landing would be like; and all of our practices, they were not as good as the real thing. We got back more data, and got more information from the spacecraft than we were really expecting to be getting.
So we're still in the ... trying to figure out what's going on. We've started to get a little bit of color data back, which kind of is helping us figure out things. But we're still really in the early stages, just trying to get oriented and figure out what we're going to do for the next 90 days.
B: Diana, was there a problem with the parachute? One was released a little, like 7 seconds late or something like that?
D: You know, I'm the wrong person to ask on that stuff.
D: I haven't really been following that. I've been kind of working nights, and because of when Mars and the Earth are close together, when the science data has coming back, and I've just been so busy looking at pictures, I've not really been following a lot of the technical stuff.
S: Okay, do you have an update, or are you aware of the situation with the robotic arm? Apparently, they were having a little bit of difficulty unstowing the robotic arm. Is that working properly?
D: Yeah, it's working properly as far as we go. We start at the ends though. We're doing, we kind of do everything in little steps. And we're waiting for data to come by. So, from the science team perspective, we're kind of moving full speed ahead. I think the problem was because we're looking for organics, the arm has to be sterile. So it was in a kind of a bag to keep it from getting contaminated with stuff. And so there was initially some concern about how that bag had deployed.
But when they looked at it closer, they think they're pretty good to go. So, as I said, I don't know the details of exactly what's going. But from a science perspective, we're still, we don't foresee any problems with the arms at this point.
B: What's the delay? What's the signal delay now between Earth and Mars? What is it? How many light-minutes away are we? I forget. Is it ...
D: I think it's something around, close to 10.
B: 10 minutes?
D: Yeah, 10 minutes.
B: How much of what the lander's doing now is kind of like prepackaged commands that it does all by itself, and how much is you have to actually, "Alright, now do this." And then you have to wait for the delay, the 20 minute delay or whatever until, if you can confirm it.
D: We don't do anything with what would be called "real time" and stuff. It's all kind of prepackaged. How we run things is, when the lander wakes up every morning, we give it a list of activities it's supposed to do all day. And then in the late afternoon, when the spacecraft, when the orbiter flies over, it sends all the data about what it does, and then it comes back to Earth. That's kind of what I'm kind of waiting on right now. That data comes back at night. So we're waiting for that data.
But once we tell it what to do, we don't know until pretty much 10 hours later what it's done, and how things happened.
D: And so what we do is when that data comes back, we then try to understand what the spacecraft did, and then try to move forward. Right now, because we're very, very early in the mission; we're still checking out a lot of the instruments and systems and stuff. And so we have a list of things that we're kind of going through step by step to get the spacecraft fully up, running, tested, stuff.
So, and if one thing goes a little off track, we'll start something else, and things. But so far, everything's just been going very, very smoothly.
S: Now just about the mission; the Phoenix lander, is it at the north pole of Mars?
D: Um hm! It's not at the north pole, it's kind of above the arctic circle. So, where we've landed, there's permafrost and ground ice, but there's not a lot. There's not like ice on the surface that we can see at this season.
S: Yeah, I can see the picture, on the website. And it looks like soil. Yeah, so there's no snow or ice on it. Okay. Has that, what's the season on Mars, right now?
D: It's coming into, let's see, it's (inaudible) 90, almost, which is, it's almost full summer.
D: It's coming into summer. It's late spring, early summer type of there.
E: Diana, is it true that you have to get your data collected in the next three months, and that's approximately when you're expected to perhaps lose some contact with the Phoenix?
D: Well, because we're solar powered mission, as we move out of summer into fall, we start getting less and less power. And so, at the three month mark is kind of when the power levels are going to start going down. We still expect the Phoenix lander to be alive, but it's not gonna have a huge amount of power to do things like digging and stuff. And so we probably doing more meteorology and imaging and stuff.
At some point, probably, and we're not exactly sure when, you'll start moving into hardcore winter, where the sun won't be above the horizon, and the CO2 icecap will come down and cover it. Since we're a solar powered mission, once we start getting to the point where we don't really have very much sunshine, the mission will end.
S: Is there any possibility that next Martian spring, it will thaw out and could be used again? Or really, that will be it?
D: Well, we're gonna try to see if we can communicate with it. But it's very unlikely, and it certainly wouldn't be able to be used like it is being now. There's things on the lander such as batteries, which will have frozen hard and broken. And a lot of the electronics equipment just haven't been tested to survive dry ice. And so all it takes is one electronics board breaking, and we won't ... yeah.
But, I mean, I think people still want to try to see if it, on the off chance it did survive. But it will be, it won't be doing science again.
S: I see. Now you mentioned a couple times that it has the potential to test the soil where it is for organics. So, just to be clear, if there's life in the soil, where the lander is right now, this lander will detect it? It has the equipment to detect it?
D: I was real careful when I said organics and not life. There's a lot of other places besides life you can get organics. You can get it from meteorites in the sky. And there's non-biological processes that can detect organics. And so you really need to have something pretty spectacular and pretty definitive to say you can detect life.
But you can look at, "Is the place some place where there are organics? Is there evidence that the water has been liquid?" And draw some pretty good inferences on how habitable is it. Could life survive? I think unless something really, really spectacular falls out, where there's not a lot of ambiguity, and people can argue both ways. Scientists kind of tend to be pretty conservative about this stuff.
The other thing is, we're gonna have to be very careful about interpreting any of our organic results. The spacecraft came from Earth. And the Earth has organics with it. So, we have things like a blank that we brought from Earth to kind of do as a control and stuff. And so saying something directly about life is going to be ... take a long time, and we're gonna have to be very cautious about.
S: So, you might find that there's water in the soil, that there's the raw materials for life, and an environment where life could potentially survive. But you're probably not going to find definitive evidence that life is actually existing either now or in the past on Mars with the kind of analysis you're doing.
S: Okay, so we're not, in the next three months, we're not gonna see headlines, "Life Discovered On Mars."
D: I would be very cautious about saying that that's going to happen. I mean, everyone always wants to discover stuff, and it's not outside the realm if we got something that was just so spectacular. But given what most people think the environment and climate, and how these processes work, most people, when they talk about life on Mars are talking about microbial life.
If you found a dinosaur bone, but no one who ... really expects that kind of discovery. It's really gonna take a lot of lines of evidence and stuff. And probably, if we find something that's very suggestive, it would probably take another mission specifically geared for detecting life to really confirm things.
But you have to keep in mind that no one has found any organics on Mars before. In a lot of places, the soil is very hostile to any kind of organic matter, even from comets and meteors and asteroids hitting Mars, the organics are broken down by chemicals in the soil. And so, what we're trying to do is test the hypothesis that if organics are there, it can be preserved in the ice, which is protected from the really harsh chemistries of the soil.
S: Is part of the goal of the soil science of this mission to test how habitable Mars might be for future human missions to Mars? Or is that not one of the missions here?
D: There is some interest in that. A couple of the interests, especially the MECA Instrument, was actually selected in part with getting information for future manned exploration. For instance, we're gonna make the first ever measurement of the pH of the Martian soil, and see if it's acid or not. And that's very important from an astronaut health point of view. Is if you're coming back into your module, and you're tracking dust; if it reacts with water and stuff in your environment chamber, and turns into something that's very acidic and corrosive, you really want to know that.
So there's a lot of basic information about the soil that we're going to get for the first time ever. This is the first time we'll have done a both a wet chemistry experiment on Mars, where we're looking at salts, and pH, and electroconductivity of the soil when it's mixed with water. And also, the first time where we've done a depth profile of the soil, and hooked it up to the TEGA instrument, where we've baked the material out, and looked at the gases coming out, and the compounds coming out, searching for organics, and water, and CO2 from carbonates, and SO2 from sulphates.
And then there's one other thing that I'm very interested in, is looking at, as we use the arm to dig through the polygons, looking at that soil horizon, and seeing if there's evidence that there's been liquid water moving salts and compounds through the soil to different layers.
S: Now, what are the polygons?
D: They're called ice wedge polygons. And they're caused by differential expansion and contraction of the ground, with ground ice. The kind that most people are familiar with if you've ever seen a mud puddle dry out, and you look at the mud puddle, and you see cracks, and then flat places in between them, those are also polygons. So, when things change their volume, induce stress, and to relieve the stress, you form cracks. And so, as permafrost expands and contracts with temperature, season, and also with potentially with liquid water falling down into cracks, you form similar landforms in the Canadian arctic, and Antarctica, and places like that.
And so, we've landed at a place where there's ground ice somewhere in the 2 to 7 centimeters from the surface. And we're gonna be digging down into that ice.
B: Diana, is there another name for the soil on Mars? It seems to me that even the word "soil" is maybe a bit of a misnomer, because the soil on the Earth, not only does it have the broken down rocks and the minerals and things, but it's got the humus, I think it's called, the organic matter which, alright. Maybe there is minute amounts of organic matter somewhere on Mars, but it's really not a major component of the soil. Do they call it, do they have another name for it? Is it really appropriate to call it soil?
D: It is technically not appropriate to call it soil. The technical name is regolith.
B: Oh, like the Moon, then, alright.
D: Yes, like the Moon. Most people who study Mars say "soil" when talking to the general public just because regolith is kind of jargony. But you're right. Technically speaking, it's regolith, not soil.
S: Regolith sounds cooler though, I think.
D: Yeah, regolith sounds cooler, and, yeah. It has to do with fine grain in particulates produced through non-organic processes. On the Moon, it's primarily impact cratering and micro-meteorites. That process plays a lot of role on Mars too, but you also have aeolian wind-produced materials. But you also will find people talking about the regolith of the icy satellites of Jupiter, with Europa and Ganymede, which are ice particles and stuff.
S: So, Diana, you gonna be busy as heck for the next three months.
D: Oh yeah. Yeah, I packed up and moved from Pasadena to Sodford to do this.
S: So you're just gonna be living there, just doing this non-stop for every moment you have the mission.
S: And it's just every day, you're waiting for the data dump for that day?
D: Yep. Pretty much. Then trying to figure out what things mean, and interpreting it. Mars' day's about 40 minutes longer than the Earth. So over the course of about a month, my work day rotates around the clock.
D: So we're kind of, every day we're in a different time zone.
D: Right now, we're going into working nights and stuff for the next couple weeks.
B: Diana, I assume you've been working on this project in some manner for quite some time; months or maybe years?
B: Could you even describe the feeling when you finally got the word that the lander was intact, on the planet, and didn't disappear, or have a metric problem, or anything. That feeling, it must have been amazing to think, "Wow! We're here, and it's okay. And now I could do real work."
D: Yep. I was part of the '98 mission, which we didn't land successfully on; and so were a lot of people in those teams. And it's kind of like this huge kind of weight not really being sort of kind of melted away, and it's just like a lightening of the spirit and how you were feeling. It's like I haven't really realized how anxious and nervous I was about the landing until after we had successfully landed, and we started getting information back, and I realized it's better than I really had anticipated. You kind of steel yourself in these situations to be prepared for the worst ...
D: and then you're just very, very happy.
E: Was the '98 mission the one that had a miscalculation of some sort, and that took it off course?
D: Well, that was for the Mars Climate Orbiter. It was unclear what happened exactly with the Mars Polar Lander, but it probably had something to do with the landing system. And because we were using the same landing system, we ended up doing a lot of tests to really understand what was going on, and possible causes.
I don't think the real, the final cause, they had a total smoking gun, "It had to be this." There were a lot of, there were several possibilities.
S: Well, Diana, congratulations on a successful landing. And good luck. And perhaps in three months from now, we can get you back on the show to talk to you about what you found.
D: I would love to. Thanks so much!
S: Alright, take care.
B: Thank you!
Science or Fiction (1:00:20)
Question #1: A new study shows that public schools are just as effective as private schools at teaching math skills. Question #2: Researchers have developed the first smell map - describing which chemical structures result in which smell sensations. Question #3: Yale computer scientists have devised an e-mail algorithm that they claim will eliminate, if fully implemented, 98% of all SPAM.
Quote of the Week ()
'The high-minded man must care more for the truth than for what people think.'- Aristotle
S: The Skeptics' Guide to the Universe is produced by the New England Skeptical Society in association with the James Randi Educational Foundation and skepchick.org. For more information on this and other episodes, please visit our website at www.theskepticsguide.org. For questions, suggestions and other feedback, please use the 'contact us' form on the website, or send an email to 'info @ theSkepticsGuide.org'. If you enjoyed this episode, then please help us to spread the word by voting for us on Digg, or leaving us a review on iTunes. You can find links to these sites and others through our homepage. 'Theorem' is produced by Kineto, and is used with permission.