Where Do We Come From? – Exploring the Origins of Life Lab

[Mat Kaplan]: Where do we come from? This week on Planetary Radio.

Welcome. I'm Mat Kaplan of the Planetary Society with more of the human adventure across our solar system and beyond. Where do we come from? Which is to say, how did life begin and did it only happen here on Earth, or do we live in a universe teeming with life?

These are arguably the most important questions in science. Researchers at McMaster University in Hamilton, Ontario have created the Origins of Life Lab to help provide the answers. We will meet two of them in a moment. I hope you'll also join us for this week's What’s Up with Bruce Betts.

Work on the origin of life is taking place at institutions around our world.

Ralph Pudritz, Maikel Rheinstadter and Yingfu Li are the partners who have created the Origins of Life facility at [00:01:00] McMaster. It contains a marvelous new device they call the Planetary Simulator. This stainless steel test chamber may reveal some of the vital steps that could have led billions of years ago, to the natural development of self-replicating molecules and then living cells.

Ralph is an astrophysicist while Maikel is a biophysicist. They joined me from their offices a few days ago. Prepare yourself for a deep dive into what might be our own Genesis.

Maikel, Ralph, gentlemen, thank you very much for joining us on Planetary Radio and congratulations on the creation of this new lab the McMaster Origins of Life lab, which we'll be talking about today.

Good to be on.

Thank you very much for having us.

[Mat Kaplan]: It's, uh, quite exciting, actually. I was extremely intrigued when I read the press release that came from your University. When I read about this, I immediately thought of the, the justifiably famous [00:02:00] Miller-Urey Experiment 65 years ago. And as I'm sure you guys know it showed us that the building blocks of life, amino acids can be generated when energy in the form of, in their case an electric spark is produced in a flask containing simpler compounds that might have existed on a very young Earth. Is this new lab, that you guys have created and are working with, is it in any sense, a 21st century descendant of that groundbreaking work?Ralph?

[Ralph Pudritz]: In a sense it is, Mat. It’s Origins of Life 2.0 in that context. So in our experiments and the view we are taking is that, we are imagining that by some mechanism we already have in this case, since we're interested in genetic materials like RNA that is in all cells all organisms how it's built out of building blocks called nucleotides.

So for the first set of experiments, we're imagining that these are already delivered by meteorites or perhaps built [00:03:00] through a planetary atmosphere process and then asking the next question what then? how did you build the genetic materials that are going to lead to that? If we're lucky we'll demonstrate reproducibility and evolution on worlds to life.

[Mat Kaplan]: My boss, Bill Nye the Science Guy, he says the two big questions that we want to answer in science are: Where do we come from? And are we alone? And it would appear that you hope to answer both. Do you see it that way Maikel?

[Maikel Rheinstadter]: The Miller-Urey Experiment was indeed a very fundamental and exciting experiment.

So what they found is that you can produce the building blocks of proteins and peptides and RNA and DNA on Earth through very basic chemistry, but the Miller-Urey Experiment kind of failed to polymerize these building blocks into proteins peptides on a DNA, and that's what we want to do in our [00:04:00] experiment.

So if we are successful in this one, this would be indeed, would indeed show, how the first very basic cells could potentially have formed on the Earth and also on other planets.

[Ralph Pudritz]: I'll just follow Maikel’s remark on that, the second part of the question. Are we alone? In other words, does this occur beyond the Earth and other habitable terrestrial planets.

We already have through astronomy observations, we know of the existence of perhaps a couple of dozen of these rocky potential worlds, but around other kinds of stars. And so our simulator was very carefully designed so that we can simulate say, the radiation fields and in other atmospheres that would be present on other habitable planets and other words other planets that have liquid water on them.

So that's the way we're going to attack the question, are we alone, it could occur in other off Earth environment.

[Mat Kaplan]: Why is RNA, ribonucleic acid, the kissing cousin of [00:05:00] DNA? Why is it so central?

[Maikel Rheinstadter]: The way we work today, is our bodies work based on proteins and DNA. But these are very complicated molecules and once you have DNA then you can use proteins and enzymes and such to cut and to replicate and duplicate RNA.

The question that we ask is how did the entire thing start?

So we take a bottom-top approach. It is conceptually much easier to think of starting the process with RNA and then building it up to DNA and protein and such later. So this is why, in our approach, RNA is the central molecule for us.

[Ralph Pudritz]: The DNA protein world that we have now is, as the heart of our genetic code, is far too complicated to have been the first and appeared and most scientists working on this problem think, we would all agree on this point. There was a breakthrough in the 19 late 1980s that show that [00:06:00] RNA is a molecule that doesn't need all this elaborate machinery to reproduce itself, It can do this all in its own. It's a unique molecule that can, is what we say catalyze or engineer its own replication and that's why we see it in, as Maikel would say all forms of life. So it seems to be the more fundamental molecule thing that may have been there first, as Maikel has suggested.

[Mat Kaplan]: The question that then comes to mind, which we don't have to answer today is, gee I wonder why life moved on to DNA if RNA was capable of doing so much on its own. I don't know. Do you want to address that?

[Ralph Pudritz]: That's pretty hard for us. I'm, I mean that is a lofty goal. But I think we need a good solid start on something that's simpler, I mean, both of us are physicists. I'm an astrophysicist and Michael is a biophysicist and I think starting on the most fundamental simplest possible level on a problem is [00:07:00] kind of a natural way to go, we think. If we get this right or somewhere interesting, then that may lead to such other thoughts. But for the moment that is sort of just a very complicated Machinery.

[Mat Kaplan]: Hmm, speaking of the foundation of this work, Ralph, could you tell us a little bit about the theoretical work that you and and yet another McMaster colleague, Ben Pierce published that led to the creation of this lab.

[Ralph Pudritz]: Now, that’s a very exciting project Mat.

My student, Ben Pierce and myself in collaboration with two colleagues at the Max Planck Institute for Astronomy in Heidelberg, joined forces to try to understand, what would be the fate of nuclear bases. That is the basic building block that goes into these RNA nucleotides. That molecule, there's four of them.

That is delivered, in the early Earth by the vast influx of meteorites. The Earth was built by meteorite again planetesimals, large bodies colliding here to build it up, [00:08:00] but the meteorites, the class for them also brought huge amount of organic material. This was first pointed out in a great paper by Carl Sagan in the early 1990s.

Enormous bombardment, we talking the Bartman rates of trillions of times greater than the Earth today. When the Earth formed, that huge influx of nuclear bases, what would be the fate of these as they were dropping into warm little ponds. Paper calculated in a fair bit of a detail, what would be the rate at which they would have this kind of infall of these molecules, what happens to them in their ponds?

What kind of concentrations could they build, to how fast would they polymerize? You know join up into these long molecules in the face of Destruction mechanism. Like the very strong ultraviolet radiation field on the earth at that time. Remember before life the Earth has no oxygen. There's no screening ozone layer for us.

So those early molecules might have had a tough time [00:09:00] in a radiation field like that. So we looked at as we call the sources and sinks how these molecules the build-up to the polymers and what can destroy them and did a basic calculations in the environment of warm little ponds on the earth. And that that for us is at least for me is that really the kind of theoretical basis of some experiments that would be very interested in pursuing.

[Maikel Rheinstadter]: The different models where and how life has formed on the earth. Some people push forward the idea that life has formed in the ocean and hydrothermal vents. Some people are looking for traces of life deep inside of ice at high pressure points. We follow with the new lab, the idea that life has formed in these warm little ponds. This idea was also highly inspired by David Deamer, from University of Santa Cruz, who is pushing forward this idea for many, many years now and who has kind of infected us with it a few years ago, the discussions with him and the collaborations with him, eventually led to the application of such ideas to such a lab and to the building of this lab.

[Mat Kaplan]: I was also fascinated to read about another element of this work, which apparently you will be attempting to simulate in the planetary simulator.[00:10:00] Which we will be talking about in a moment,but this idea of wet and dry cycles which I guess someone intuitively, I would have thought would not be very good for the progenitors of early life. But maybe I'm wrong about that.

[Maikel Rheinstadter]: The cycles, have indeed turned out to be one of the key points in the process of polymerizing RNA from the basic nucleotides because if you just mix these nucleotides in water or in in these ponds then with time not much happens.

But if you drive them out, if you have your pond and the pond dries out at the [00:11:00] beginning of the summer than all these molecules get dried out at a very thin layer at the bottom and you reach extremely high concentrations of these molecules and you suppress the mobility of these molecules and this is the time when they can react with each other and start forming dimers and trimers and longer and longer chain of polypeptides.

So you need two cycles of hot and cold temperatures and you need two cycles of wet and dry to make this process happen.

[Ralph Pudritz]: Imagine you're trying to build a long train and you've got a bunch of box cars lined up on the track, but you need to link them up to form the train. The boxcars are the nucleotides and the long train will be your RNA molecules. In order to get the hooks to form to latch together the links between the boxcars, that is what we call a bond and that forming that chemical bond requires that you get rid of water.

So that's what happens when you dry these systems out. So then you [00:12:00] get a few box cars at a time, you know forming these chains and as this goes on now, there, if you have to link two inks, if you throw down you wet again things move around you drying up, couple of boxcars together find another two and they link together and so on and so on. The another important part actually it came out in Maikel’s own experiments with David Deamer, was that this can be probably facilitated very much, if you have a surface like a fatty acid like a lipid, as we call it like soap films on which these molecules rest. That is an ideal surface to help this process of what we call polymerization. And that's a very interesting.

[Mat Kaplan]: You know, that goes in the direction that I was going to ask you about because I have read that the formation of membranes is probably also key to understanding the formation of the first living cells.

I mean, Maikel, is that kind of where this might be headed, talking about lipid bilayers? [00:13:00]

[Maikel Rheinstadter]: Exactly. So, the fundamental difference between what we are proposing in the new lab and the Miller-Urey Experiment is that the Miller-Urey Experiment happened in an isolated environment. In a glass flask basically, but we think that the environment, it's extremely important. So the presence of porous rocks the presence of inorganic solids the presence of other organic molecules, like the lipid molecules is extremely important for the polymerization of these nucleotides eventually.

[Mat Kaplan]: Let's talk about that lab and in particular this beautiful piece of Hardware, which we will link to information about the lab and our audience can take a look at what you're calling the Planetary Simulator, please, maybe Ralph you could tell us a little bit about really what will be the focus of your work.

[Ralph Pudritz]: Yes. So, the Planetary Simulator is well named because what it attempts to do- what it will do- is allow us to control in a very controlled[00:14:00] way kind of diet lap if you will, different kinds of planetary environments, what we're doing is breaking away from kind of clean test tube chemistry and an earth environment in a clean lab, but we're recreating the somewhat complicated geological environments on different kinds of planets.

Your viewers will see there's a very interesting set of a cylinder like looking objects on this outer part of our simulator those contain a series of lighting devices LEDs and various other kinds of things that go from infrared wavelengths very long wavelengths all the way to the ultraviolet wavelengths and we can dial up if you like, the fingerprint the radiation fingerprint that we call a spectrum of any star. So the Sun has red or yellow, it will have a lot of UV in its early life. We know that the most dominant kind of star in the universe in the in our galaxy is [00:15:00] a dwarf star. It's actually red. It's maybe a tenth of the mass of the Sun and a habitable planet there would be inside the orbit of mercury.

So their days are very much shorter, obviously. A year would be maybe 15, 20 Earth days or something like this. There's a different kind of radiation.

So, those kind of red dwarf stars, M stars as we call in astronomy terms, have lots of UV, very dangerous in that way. But their radiation is more skewed to red optical light. So, by that we can control the radiation that will affect the kind of chemistry. As Maikel mentioned. We control the humidity, the dry wet cycles, the temperatures that we can tune to whatever we think we want for planetary conditions. We're looking at habitable conditions on all these planets. So in those conditions water will always be liquid.

But there's still a huge number of trends than we have free to alter. The physical and kind of planetary [00:16:00] environments we're talking about, it was deliberately done that way.

This will allow us to address this question. Are we alone? In other words, if we found that we could get these RNA molecules to be made in an earth like simulation, could we find similar sequences in another planetary environment or not? Would that be prohibitive and if so, why would that be? That's really what we would be driving at with this.

[Mat Kaplan]: Very exciting Maikel, I wanted to go back to what you were saying about getting away from you know, the sterile lab glass and putting in other kinds of stuff that we've heard from Ralph about the different kinds of environmental factors you'll be able to control. But,you talking about basically getting, if not your hands, at least your samples dirty in a sense, having all kinds of stuff in there, like clay.

[Maikel Rheinstadter]: That's right, dirty in a very controlled way.

So what our students are doing the lab is they try to recreate these warm little ponds [00:17:00] and they recreate them in different environments.

And in these ponds, that would be salts. There would be clay, so often you have like a muddy layer at the bottom of a pond which is made out of different types of clay and we think that these environments are extremely important not only for the formation of RNA, but they may also be very important for the sequence that the nucleotides may form on these particular pieces of RNA.

So in some ponds, even if you can produce on this piece of RNA, may not carry any biologically relevant information while in other ponds, which exists on different parts on the earth and different environments and have different ingredients they may produce RNA which is highly functional and biologically relevant.

It's very Advanced chemistry that we play but we try to play it in a dirty Way by mixing things together and get away from the controlled clean chemistry [00:18:00] environment that usually have.

[Mat Kaplan]: I love that learning about the origin of life may require us to get our hands dirty.

[Maikel Rheinstadter]: Exactly

[Ralph Pudritz]: An interesting point that bears on the theoretical ideas is, would salt be important? You know if you form life in salty oceans. Salt is a problem, for making these such large molecules that's well-known. So we can control that very well by say experiments in which we would vary the salt concentration as an example from freshwater, perhaps take more something like seawater and just check what happens.

We think that, that's why, in our view, it's more plausible to think that life began in freshwater. One little pond and not an ocean just for that simple fact of what salt does, to inhibit this kind of formation of molecules, is a topic that's pretty well-known.

So I think the other thing that intrigues me looking at the Maikel's, the way Maikel has set up the experiments. Basically Maikel sets up [00:19:00] mini ponds.

They're very small things. We can put in you know, maybe 90 such many ponds in the simulator at the same time.

[Maikel Rheinstadter]: Yeah, that's exactly what we do. is so be called the mini or micro ponds. So depending on where we think these ponds would have been formed, would have formed on the earth, they would have slightly different compositions. So the compositions on the one hand and also the type of cycles that you run, they may play an important role for, not only for the formation, but also eventually for the sequences that you get. So while some regions on the earth may still produce, have produced RNA in ponds this may not have been functional in the biological sense while in other areas on Earth, there might be ponds with different compositions and they may have produced the RNA that was needed to form life and eventually for more complex cells as well.

[Mat Kaplan]: There is a [00:20:00] video that listeners can check out, it's in the article that we will link to and I'm going to guess that what I'm looking at in a portion of that video are some of your students creating these little mini ponds.

[Maikel Rheinstadter]: Exactly exactly.

So because we know, we assume that we know, what was in these ponds and we have all these ingredients in our fridges and freezers and such, so it's relatively easy for us to mix these things together, form these ponds and eventually dry these ponds out on these little chips and because they are teeny, that's very small, one by one centimeter, we can run about as well as said, about 90 of them at the same time of the simulator.

This a very efficient way of testing a lot of parameters at the same time and see which one eventually is successful in producing RNA

[Mat Kaplan]: . So you have begun to expose these many ponds subject them to the planetary simulator, is the work underway?

[00:21:00]

[Maikel Rheinstadter]: Yes, we did. It is underway. Everything worked actually much better than expected.

And after the machine was installed back in July, in the summer. After a few days, we were up and running simulations already and we were extremely excited to see the first results already after a couple of days.

[Mat Kaplan]: So, if we're lucky there may be some more Publications ahead. What, if you're successful, in showing how RNA may have formed on the early Earth, that will be, not an earth-shattering perhaps, but a very important development in the history of science, I think.

[Maikel Rheinstadter]: I would tend to agree, so I'm cautious. So, I would say that if we find out a process by which RNA can form under these conditions, we have a very solid proposal on how life can possibly have formed on the early Earth and also on potentially habitable planets [00:22:00] out there.

[Ralph Pudritz]: I agree. This is a tremendously exciting.

I would probably take it one more point in the way we're thinking of the experiments. It'll be one thing to show that we could maybe build RNA molecules like trains that are, have got 60 cars long, RNA with 60 of these nucleotides linked together. We know in biology that these are already functional they have functional purpose, but what we don't know in the lab and the really big unknown is supposing we got are polymers that long to form, which of them if any, would be successful in replicating themselves. That is completely unknown to us at the moment.

We're here. We're really on our own and no doubt that why we are varying the environments, no doubt, you know an RNA molecule will be successful somehow within its own environment.

It is the best kind of molecule to be able to replicate in that [00:23:00] environment. If you know what I mean, and that basically brings in the idea of how molecular Evolution would occur. We have no idea of how successful we will be yet in finding whether there are any of these molecules that form that would have this ability to self-replicate only if they do that, could we really say that yes, we've taken the first step toward something that you know, one day we could think of as living.

And I would say the other part of this that you mentioned before Mat, is that, is the disassociation between the RNA and the lipids. The fact that, the experiments, that when you drop a meteorite on the pond, it’s full of these lipid molecules which quickly form these little bags in which the nucleotides get trapped. So automatically, you are in a situation in which the RNA is building itself into some kind of a membrane, with that, since that's a natural thing that happens in the physics and chemistry. We're [00:24:00] very interested to see if that is going to play an important role in this whole thing of selection and ultimately reproducibility that a lot of unknowns here, very exciting.

[Mat Kaplan]: RNA in little bags, courtesy of meteorites. I mean these sound like protocells.

[Ralph Pudritz]: Indeed

[Maikel Rheinstadter]: That's exactly what we have and I think after our first preliminary experiments that we have run out over the summer. We have seen evidence for the formation of these protocells already, much faster than we expected actually, but Ralph is absolutely right, the critical question that we ask here is, even if you can make, even if you consider the size RNA and even if you can put them into these very simple protocells, will they at some point start acting as a biological system?

So the question is even if you can still make RNA using some chemistry, we still [00:25:00] have to make the transition into a biological system which is able to serve, replicate and show some sort of metabolism. And that's the big mystery there.

[Mat Kaplan]: So, long ways to go still, but it sure sounds like a very important step that you're taking. Saying that this effort is multidisciplinary seems like an understatement.

Ralph, I bet you'd agree with that and I'm wondering if you could say something about your other colleague who isn't online with us today. That's biochemist Yingfu Li, another colleague of yours at McMaster.

[Ralph Pudritz]: Yes, indeed, this is one of the greatest examples, I think, of interdisciplinary science at its best.

As an astrophysicist, I can bring certain ideas and knowledge to the table, as an example, the way that molecules are made in space, brought to Earth, the conditions of the young planets and their atmospheres. I would have no background in the biophysical setup, the kind of experiments that Maikel is trying to do, animizing membranes and their physical properties, looking for evidence on about how polymers would form.

[00:26:00] And the third person in our trio, Yingfu Li, is a leading biochemist. His own research is on molecular evolution, in fact, finding DNA sequences that are very successful in performing certain kinds of functions. So I think a success in this project needs- absolutely requires- all three of these kinds of expertise together. And this effort came about at the Origins Institution at McMaster, which I was the founding director of, which was a very deliberate effort to create such a program. Actually we even have a graduate program where students can come and work on these types of things, and what we call a Collaborative Graduate program at McMaster that's unique in Canada and one of the few in the world, joining a few such places in the United States, in which we can really bring together not only faculty but students to be trained very [00:27:00] deliberately in this interdisciplinary kind of away.

[Mat Kaplan]: If I was a student with an opportunity at McMaster to participate in this kind of work, I think I would consider myself very, very fortunate.

I'm going to take a shot in the dark here to to end our conversation: have either of you ever read the classic science fiction story written way back in 1941 by Theodore Sturgeon called Microcosmic God?

[Maikel]: No, I haven’t.

[Ralph Pudritz]: Very unfortunately, I know that name very well, but I didn't.

[Mat Kaplan]: I highly recommend you take a look, it is a very far cry from what you are hoping to do with the Planetary Simulator, what you're hoping to achieve, but I recommend it highly and we'll put a link up to that if we can find the story online.

It's actually about a scientist who sort of develops a little microcosmic world in a sort of Planetary Simulator and eventually comes up with very fast-living, intelligent life within his simulator. I suspect [00:28:00] you'll be satisfied if you achieve quite a bit less than that.

[Maikel Rheinstadter]: Absolutely.

[Ralph Pudritz]: Fascinating. Once again, art leads.

[Mat Kaplan]: Gentlemen, thank you very much, and I absolutely wish you the greatest of success with this work, even if it is unsuccessful in creating more of the more complex building blocks of life, including RNA. That will be very valuable in itself, of course, but boy, will it be exciting if you start getting molecules that seem to know how to replicate themselves out of this little device that now lives in your lab up there at McMaster University, the Planetary Simulator.

[Maikel Rheinstadter]: Absolutely. Thank you very much.

[Ralph Pudritz]: Thank you so much, Mat, for your interest and that of your audience.

[Mat Kaplan]: Time for What’s Up on this post-election day of Planetary Radio. Bruce Betts is the Chief Scientist for the Planetary Society. He joins us.

As we speak, it is still election day, so nobody can tell from how we sound what we think of the [00:29:00] results because there aren't any yet.

[Bruce Betts]: That is correct Mat.

[Mat Kaplan]: He said in a most somber fashion.

[Bruce Betts]: But I think it's only the US Election day, but…

[Mat Kaplan]: You're absolutely right. I don't know, maybe it's election day somewhere else in the universe, but…

[Bruce Betts]: They should elect a President and Vice President of the universe. We’d have to fight over who is- anyway...

Oh goodness. So, we've got in the evening sky Jupiter, pretty much gone, really tough, maybe right after sunset low in the west, but we've got Saturn in the southwest in the early evening and then Mars still bright in the south. And you can use Mars to help you find the star Fomalhaut, or “FOAM-a-lot” which is the only bright star in the Autumn Sky again for Northern observers, Northern latitudes only bright star in the Autumn south.

But [00:30:00] right now you got bright reddish Mars, and if you look to the lower left of that- about two fists widths held at arm's length- you'll find Fomalhaut, which is part of the constellation Piscis Austrinus, the Southern Fishes. And Fomalhaut vaguely means the fish's mouth.

[Mat Kaplan]: And I've always wondered how to pronounce that star’s name, and I'm proud to say that you haven't helped me a bit.

[Bruce Betts]: Nope. Not a bit. “FomaHOWD”?

And if you're in the up in the predawn: one, I'm sorry, and two, check out Venus looking super-bright low in the east, near the bluish star Spica. Or “Spike” or “SpEEka”.

All right, we move on to This Week In Space History. This day in 2014 Rosetta's Philae Lander became the first spacecraft to land on a comet, in 1971 Mariner 9 became the first Mars Orbiter.

All right, we move onto Random Space Fact. [00:31:00]

[Mat Kaplan]: I love it.

[Bruce Betts]: The Dawn mission was just recently retired as it ran out of fuel after all those years. Let's reflect: it was the first spacecraft to orbit two extraterrestrial bodies- Fest and series- and the first to visit a dwarf planet, Ceres. Also, a little tidbit that with all the glorious successes one can easily forget, Dawn was canceled at least a couple times due to cost overruns and technical concerns before being scheduled for launch and what turned into a very successful mission.

[Mat Kaplan]: And we'll get Mark Raymond, perhaps others, back on the show soon to give us a little bit of a wrap-up report on that mission. Although I'm sure like all these missions- planetary science missions- the data will be entertaining scientists and the rest of us for years to come.

[Bruce Betts]: Oh, yes, they gathered a lot.

All right, we better move on to the trivia contest because it was weird and I'm curious what [00:32:00] people thought of it. So my question was in an unrelated coincidence, what sequence of events that will occur for the BepiColombo Mission can be characterized by the first three primorials 1,2, and 6. How'd we do?

[Mat Kaplan]: Let me get the winner out of the way quickly so we can go on to some other really fun stuff. Mitch Roberts, I believe a first-time winner in Mankato, Minnesota.

[Bruce Betts]: Vikings!

[Mat Kaplan]: Of course. That series that you proposed, it stands for: one flyby of Earth, two of Venus, and finally six of Mercury before BepiColombo goes into orbit around that rock that is so close to the Sun.

[Bruce Betts]: That is exactly what I thought was the intuitively obvious answer.

[Mat Kaplan]: Congratulations, Mitch, who says he loves the show. He joined the Planetary Society less than a year ago, he says he's listened to every episode. I don't know if he's one of those crazies who's gone back to the beginning of [00:33:00] time and listened to our entire 16-year history, but Mitch, whether you have or not, welcome, and we're glad to have you on board as a member.

[Bruce Betts]: Just a little tip you may not want to call our listeners “crazies”.

[Mat Kaplan]: Especially the members. Oh, they know I'm mean it affectionately. Like I do about Christopher Dangler, who also says he's listened to Planetary Radio for several years, recently became a member. He says this week's question was great fun, “I vote for more unrelated coincidences.”.

[Bruce Betts]: Okay! I will take that to heart.

[Mat Kaplan]: By the way, did you know that there is a Reno, New York?

[Bruce Betts]: Sure...

[Mat Kaplan]: I know you didn't. That's where Christopher is from-

[Bruce Betts]: It’s the biggest little city in New York!

[Mat Kaplan]: Mark Smith- here in my hometown San Diego, California- he says, “I hate numerology. This is the astrology of trivia questions.” [00:34:00]

[Bruce Betts]: Oh, oh, oh, that hurt!

[Mat Kaplan]: Howard Medlock in Lubbock, Texas. We hear from him a lot. He came up with an entirely different set of answers, almost what you were looking for. No, it's not at all what you were looking for, but it's a pretty good. One Mercury transfer module, two MPO and the MMO-the two major portions of that spacecraft are joined together- and six objectives for the mission: origin and evolution, study form interior geology structure composition craters (that's all number two), exosphere, magnetosphere, magnetic field, and- number six- verify relativity. Good try.

[Bruce Betts]: Not what I was thinking, but sure.

[Mat Kaplan]: Alright this one, prepare to have your mind blown. Steven Donaldson-

[Bruce Betts]: Wait. Wait.

[Mat Kaplan]: Are you ready?

[Bruce Betts]: Okay.

[Mat Kaplan]: Okay, Steven Donaldson in Hagerstown, Maryland. He got it right, and he says, it turns out, there are a lot of other examples of this series, 1 2 6, and [00:35:00] you know how he knows this? There is such a thing as the Online Encyclopedia of Integer Sequences.

[Bruce Betts]: Awesome!

[Mat Kaplan]: Isn't it? Check it out, it is absolutely legit, at oeis.org, the online encyclopedia of integer sequences.

And finally this from Caleb Grove in Frederick, Maryland: third baseman, Brooks Robinson, who wore number 5, is definitely one of my favorite primorioles.

Mitch Roberts is our winner this week. He's going to get a Planetary Radio t-shirt, a two hundred point itelescope.net astronomy account, and a signed copy of Bruce Betts’ new book, Astronomy for Kids, which is fully available now I’m not sure, is it the e-book version?

[Bruce Betts]: E-book version is available. The paperback is available November 13. [00:36:00] You can pre-order now.

[Mat Kaplan]: It's a signed copy of the book, right?

[Bruce Betts]: That is indeed true. It’s signed by me, so that's kind of a bummer, but yeah, signed copy.

[Mat Kaplan]: Alright. So what have you got for next time?

[Bruce Betts]: Backing off the unrelated coincidences theme for a moment.

So Dawn very successfully employed ion thrusters for propulsion on its many-year mission: what was the first spacecraft to employ ion thrusters beyond Earth orbit? Go to planetary.org/radio-contest.

[Mat Kaplan]: It's about time I knew one off the top of my head. Once again, you have until Wednesday, November 14 at 8 a.m. Pacific Time to get us this answer, and you might win a Planetary Radio t-shirt. Take a look at it. It's in the Chop Shop store, actually the Planetary Society store at ChopShopstore.com, a 200 point itelescope.net account.

By the way, we have had five winners donate their 200-point [00:37:00] accounts on itelescope to Astronomers Without Borders. And so a thousand points- that's about a thousand bucks worth- is going to go to a school with a lot of underprivileged kids in Puerto Rico, and we are very proud to be able to facilitate that, as are our five winners. And finally another copy, a signed copy, of Bruce Betts’ Astronomy for Kids, which is a great book.

[Bruce Betts]: Alright everybody, go up there and look at the night sky and think about your favorite integer series. Thank you, goodnight.

[Mat Kaplan]: Two, four, six, eight, who do we appreciate? Chief Scientist, Chief Scientist!

[Bruce Betts]: Yay!

[Mat Kaplan]: He's Bruce Betts, the Chief Scientist at the Planetary Society who joins us every week here for What's Up.

Don't forget that we're now posting complete transcripts at planetary.org/radio on the individual show pages. It may take a few hours after a new episode is published before the print version appears there. [00:38:00] Planetary Radio is produced by the Planetary Society in Pasadena, California and is made possible by its original members. MaryLiz Bender is our associate producer. Josh Toil composed our theme, which was arranged and performed by Pieter Schlosser.

I'm at Mat Kaplan. Ad Astra.