Planetary Radio: Space Exploration, Astronomy and Science - All-Sky Optical Search for Extraterrestrial Intelligence

Episode Date: November 4, 2013

A burst of laser light could let humanity know it is not alone in the universe. Harvard’s Paul Horowitz and Curtis Mead will give us an update on the technological wonder of Optical SETI that watches the entire sky for billionth of a second pulses from the stars.Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

Searching for E.T.'s flash of brilliance, this week on Planetary Radio. Welcome to the travel show that takes you to the final frontier. I'm Matt Kaplan of the Planetary Society. Harvard's Paul Horowitz and his colleague Curtis Mead are watching the sky for a burst of laser light that may tell us in a billionth of a second that we are not alone. Stick around for my conversation with him. Bruce Betts only wishes he had a laser communication system for today's What's Up segment. It wouldn't even have to be interstellar.

The LADEE spacecraft's test of laser broadband from the moon worked just fine. Bill Nye reacts to a particularly strong statement by the NASA administrator. And Emily Lakdawalla stayed up late to watch the launch of India's Mars orbital mission. Here is the Planetary Society's senior editor. Emily, I bet you know as much as any American observing this now about the Mars Orbiter mission, MOM, in India. You've written this really interesting, long post. You wrote it on Halloween, October 31st. You are pretty excited about this mission. I'm very excited about this mission. Of course, it's always exciting when a new agency enters the fray of planetary exploration.

India hopes to be the next space agency to send a spacecraft beyond Earth orbit, in this case to Mars. Their mission is the Mars Orbiter Mission, which they do abbreviate MOM. I can't bring myself to do that. And it's planned to launch on Tuesday, November 5th at about 1 a.m. Pacific time, 1430, 2.30 in the afternoon Indian Standard Time. It's going to be quite a long road to get to Mars for them, though, because they don't currently have a launch vehicle that can send a spacecraft on a direct-to-Mars trajectory. So it has to be into Earth orbit for about a month before they'll be able to pump their orbit up high enough to be able to send it onward to Mars. There are a number of other limitations

on this mission. You talk about it being a very, very light instrument package. That's right. And again, this has to do with the launch vehicle in part, although also I think science is just generally a secondary goal on this mission. This is such an ambitious thing to do. They have gotten to the moon with an orbiter before and accomplished some good science with their Chandrayaan orbiter. But, you know, they have to achieve a lot of new things for them in order for this mission to be a success. They have to have a spacecraft that's autonomous enough to deal with problems out of direct contact with Earth. They have to have a spacecraft that can cruise for nearly a year before getting to Mars and then fire up its main engine again. Just deep space communications is a new challenge for them as well. So they have to overcome a huge number of technical challenges before they can get

any science. So as far as I'm concerned, just getting to orbit with a spacecraft that's operating and sending any science data back would be a huge success for them, never mind any of the scientific results. And doing all of that on a remarkably small budget. It's a very small budget. And when you unpack the budget of what they're spending on this mission, there's an awful lot of it that's for ground stuff like new deep space communication stations. It's a very small number that's actually paying for that spacecraft. So if they can do this, it's, I think, a real, it'll be a real wake up call to other space

agencies. Can you do this stuff cheaper? Or are we about to have a space agency that can perhaps offer much cheaper launches for spacecraft built in other places? Very interesting. Well, we will wish them the best of luck. Emily, thanks so much for talking to us once again. Thank you, Matt. She is the senior editor for the Planetary Society and our planetary evangelist, and a contributing editor to Sky and Telescope magazine.

On now to Bill Nye the Science Guy. Bill, I'd like to start with this quote in the October 28th issue of Space News. It's from Charlie Bolden, the administrator of NASA. He was up before the National Research Council talking about NASA's budget and plans for human spaceflight. And he said this, the public dialogue on exploration, the public dialogue in the United States on science and technology is abysmal. We are lacking in our ability to articulate who we are and what we do. Your comment?

Let me say it was at the human spaceflight hearing. And what we are and what we do is the same thing we've been doing for several years. People go to the International Space Station and orbit the Earth. The noun exploration has been used almost exclusively to mean human exploration, human spaceflight at NASA. I'm the first to concur in every way that we haven't done anything new and cool in a long time. And if you had a mission, let's say a real mission to an asteroid, the line would be around the block. It would be around the block and across the county line for people wanting to volunteer for the astronaut corps. Now, the asteroid mission that's being proposed is based on the hardware that we hope to have by 2017 or 2021,

rather than this real drive to go to an asteroid on our way to Mars. This, I believe, is what Dr. Bolden was talking about. The trouble with human spaceflight is it's very expensive. And people, especially of my age, and Dr. Bolden's age, perhaps, is that we have a perception that we should be spending money the way it was spent during the Cold War when people landed on the moon. Humans were walking around on the moon. That's not the case right now. It takes a much longer term commitment. But our claim at the Planetary Society, our claim is that space exploration brings out the best in us as a species. By having a space program, your society just does better. That's why we have Chinese

mission to the moon, the Indian mission to Mars, the South African space program. Having a bunch of people exploring space leads to innovation and the expectations of a better future, an optimistic view of the future. And I think that's what he was driving at. Yeah, I think you're right. Speaking of embracing science, let's give people a preview of what they might see, will see on The Big Bang Theory. Thursday at eight o'clock, seven o'clock central. That's right. I am on the Big Bang Theory with Bob Newhart. And I'm wearing the Planetary Society pin, the logo pin. And everybody admired it. And John Galecki, the guy who plays Leonard, his plus one, his better half, the woman he was with, really admired the pin. And I was

honored to take it off my lapel and pin it on her blouse. It was a very nice moment. And let me tell you, when you're working with Bob Newhart, it's just exciting. The guy is so good at what he does. The crew is, everybody is so professional. It was really, it was a thrill. Thursday, November 7th. And if you miss it, I'm sure it'll be online someplace. So listeners, you get the secret code, Watch for the pin in Bill's lapel. Thanks, Bill. Thank you, Matt. He's the CEO of the Planetary Society, Bill Nye, the science guy.

Paul Horowitz is now Professor Emeritus of Physics and Electrical Engineering at Harvard University. Yet he still has his research group at the campus, and he still leads what is in some ways the most advanced optical search for extraterrestrial intelligence on this planet. Electronics and Paul go way back. He was the youngest ham radio operator in the world when he was just eight years old, and he's working on the eagerly awaited third edition of The Art of Electronics. His telescope watches the entire sky and utilizes a custom-built detector with capabilities that seem to come straight out of science fiction. But Paul gives credit for that

detector to his former PhD student, Curtis Mead. Curtis is now working on the West Coast, but he still runs the All Sky Search by remote control. I recently got both Curtis and Paul to join me for a conversation via Skype. Gentlemen, what a pleasure to talk to you again, especially now knowing that we have not one, Paul, but two PhDs on the line. Curtis, congratulations on the acceptance of your thesis and this award of a PhD from your alma mater, Harvard. Well, thank you so much. Pleasure to be invited on to be with you and your listeners, Matt. Paul, let's start with a little review of what this is all about. Now, I think most of our audience knows what Optical SETI is attempting to do, but it has been over two years since we've talked.

So give us the little, you know, 90-second review. Okay, sure. Back earlier with Planetary Society support, we started with Radio SETI looking for microwave signals. We did that for some two decades. But then following a very interesting talk that I heard from Charlie Townes, who won a Nobel Prize for the invention of the laser, we realized that laser communication was really in the same category as radio, that with the kind of technology we have on Earth now, which should not be considered particularly advanced on the timescale of

civilizations, that we could already communicate with another similarly technological civilization in the galaxy. This realization made us start to pursue a set of SETI projects with optical telescopes that is looking for alien laser flashes from our telescopes on Earth. And we did this first with the existing 61-inch Astronomical Telescope at Harvard, Massachusetts. And we started this in 1998. And then we did it in coordination with Princeton so that we wouldn't be flummoxed by signals generated locally. If they can see it, then we can see it. It isn't coming from next door.

Then we realized that it really would be nice to cover more than just a few thousand stars. It'd be nice to cover the whole sky. And that led to the first of our all-sky searches. And this launched early 2000s. And Andrew Howard was the major worker on that one. And we built our own 72-inch optical collector. I'm not sure I'd call it a telescope exactly. It's more like a light bucket. And Andrew designed a chip that was able to handle very short flashes of light and process them and look for the kind of signature that one might expect from an alien civilization. That experiment ran for a number of years and led to his thesis and to a nice paper that was published in the Astronomical Journal, the premier journal of astronomy. Perhaps the link will be posted on the website, Ontario Society.

You can count on it, yeah. And as Curtis will explain, and Curtis is the genius behind this upgrade, there were some problems with that. It was really the world's best optical search at the time, but owing to the limitations of what you could do with silicon back then, we were limited in our ability to

capture the full fidelity of optical flashes when these things came in. This thing looked at the sky with a thousand pixels that were sensitive at the nanosecond level, but once triggered by an apparent flash of light, it could only follow one-sixteenth of the coverage of the sky. And so we got events from time to time that looked for all the world like the real thing, but we couldn't see what was right around them. We couldn't see if there were, in fact, adjacent places in the sky also flashing, which would indicate clearly that it wasn't a single point in the sky, but perhaps

something like an atmospheric phenomenon, such as geranium radiation, which Curtis will tell you about. So Curtis came up with this really, really cool idea, and I'm going to let him explain it to you, for how to improve our coverage to get the full coverage, not the 116, by the way, to make the thing faster and to make the thing have 10 or 20 times as much memory storage of the event, and also to let us look backward in time before the triggering event in a very elegant way. And so that brings us up to the current date. We're running this new, wonderful, advanced all-sky camera. We have been running it now continuously for something a bit more than a year, although we haven't yet made the discovery. Hope springs eternal.

That's what this is about, right? As our boss, Bill Nye, says, the one sure way not to find ET is out there sending us a message is not to look. And so, Curtis, I have your paper, your thesis, the one that helped earn you that brand spanking new PhD in my hand. It's called A Configurable TeraSample-Per-Second Imaging System for Optical SETI. TeraSample, that's key to this, right? What are we talking about there? Billions and billions? Well, it's a great title. It gives us a little bit of a punch, you know, TeraSample.

Yes. Well, it's a great title. It gives us a little bit of a punch, you know, a terror sample. Yes. The biggest challenge in this system that we have is doing high-speed sampling of all of the optical sensors that we have in the system. The problem is doing it en masse at high speed at a reasonable amount of power and an amount of space. This has partly to do, right, with the fact that you're not going to be able to afford the kind of computing power they have at, let's say, CERN over there in Europe. You had to do this in a far more affordable, manageable way. Of course. As a university, we're on a limited budget. We don't have government-scale budgets, and we can't do everything we want. So we have to be a little bit clever about it. We don't have government-scale budgets, and we can't do everything we want.

So we have to be a little bit clever about it. We've gotten lucky in the past. Andrew Howard's integrated circuit that he developed, that was built for us by the MOSIS project. They sort of donated that. Here we donated the chips from Xilinx that are the heart of the system. My colleague Bruce Betts has also written about this, and he has some great illustrations. We'll try to use some of these on the show page that people can find at planetary.org. And they kind of illustrate what's going on here.

I mean, as Paul said, you're not just now monitoring maybe the one pixel where this possible signal from ET might be found. But pixels to the side of that, and why is that important? Where does this Cherenkov radiation fit into this? One of the background sources that we have are cosmic rays that enter the atmosphere and create a very short flash of light, just like we might expect to see from a distant laser pulse. But these are things happening in the atmosphere not far away. So what we want to be able to do is distinguish those close-up flashes of light to the distant flashes of light that we're looking for.

By being able to sample all of the sensors at the same time, we can see if the flash light is coming from a small point in the sky or over a larger area. You know, if things are close up, they look bigger. So these flashes of light that happen in the atmosphere, they look bigger than a distant laser would look. So now that we can capture all the data coming from the entire system, we can tease those two out. Basically, Cherenkov radiation has the same time signature as what we might expect

from an alien civilization transmitting laser pulse. So if all we can see is the brightness of the flash and how long it lasts, but can't see its shape in the sky, then we can't tell the difference. And the problem, one problem with Andrew's original system is that we couldn't see the shape in the sky. And Curtis has basically broken through that limitation, and we can see them. And there's a wonderful zoo of these things, and many of these are pictured in Curtis's thesis, in which you can see for yourself what a Cherenkov flash or trace of light looks like in the sky as captured by the new system. Want to read Curtis's thesis? We've got the link on this week's show page along with other great resources about the advanced all-sky camera and search. You can get to it from planetary.org

slash radio. And you can hear more from Curtis Mead and Paul Horowitz in a minute. This is Planetary Radio. Greetings, Planetary Radio fans. Bill Nye here. Thanks for listening each week. Did you know the show reaches nearly 100,000 space and science enthusiasts? You and your organization can become part of Planetary Radio by becoming an underwriter. Your generosity will be acknowledged on the air each week, as well as on

the Planetary Society website. To learn more, visit planetary.org slash underwriting. That visit planetary.org slash underwriting. That's planetary.org slash underwriting. Thanks again for making us your place in space. Hi, this is Emily Lakdawalla of the Planetary Society. We've spent the last year creating an informative, exciting, and beautiful new website. Your place in space is now open for business. You'll find a whole new look with lots

of images, great stories, my popular blog, and new blogs from my colleagues and expert guests. And as the world becomes more social, we are too, giving you the opportunity to join in through Facebook, Google+, Twitter, and much more. It's all at planetary.org. I hope you'll check it out. Welcome back to Planetary Radio. I'm Matt Kaplan. Harvard professor emeritus Paul Horowitz leads the AllSky Optical SETI program. That program led to Curtis recently achieving his Ph.D., largely based on his thesis describing creation of the advanced AllSky camera, a marvelous technological achievement that processes the terabytes of data

gathered every clear night by the All-Sky Telescope or Light Collector. How many of these candidate flashes have you been picking up since this new system was put in place in April? At the time of my thesis, we had observed for a few hundred hours and we received 300 coincident pulses that looked interesting to us that we wanted to look into further. We identified about 75% of those were just sort of detector anomalies that turned out to be nothing. Another 10% were flashes due to aircraft strobe lights, basically. You know, we're sort of in a flight path, so we do see a lot of airplanes going overhead, and our system can detect those as well. And then about 5% were these Cherenkov light flashes from Consul Grace. That's important for us because those

Cherenkov light flashes, as Paul said, do look very much like what we would expect to find in their time signature. When the real one comes, I should of course say if, but I'm going to stick with when, how will it be different? It'll light up one pixel on one detector for this tiny, tiny moment of time? If you look in some of the images in my thesis, you can see that these cosmic rays kind of look like a streak across our detector, or maybe like a large blob. And they're not a tight, compact source that is maybe one to five nanoseconds long.

Curtis, I said up front that you're no longer at Harvard. You've left the nest, but not entirely, because you're now from California, still running this search. Sounds like the story of modern astronomy. That's right. Our system is really great. It's sort of very stable. It's been running for a long time, and we've worked out a lot of the kinks. And we've set it up so that I can observe entirely remotely. And we set it up so that I can observe entirely remotely.

I log into a server we have in Harvard Mass, can move the telescope, open the roof, do all the things I need to do from afar. And it's somewhat automated so that when the morning comes, it'll shut itself off and do all the things. In the morning, I can log back in and look at the results and see if we have any interesting signals. Paul, you know, oh, just a little bit about electronics. The advances that have been made to enable a search at this level, do they have applications elsewhere down here on Earth? Again, I think Curtis is probably the guy that talked on this, but his triggering system that he designed for this using these Xilinx Vertex 5 FPGAs, using them in a way that was never intended by Xilinx, and which astonished them, I believe, when we presented this idea to them,

turns out to have potential applicability to some of the big boys astronomy experiments, in particular the experiments looking for gamma ray events, some of these large optical telescopes that are linked together, that tend to have less sophisticated triggering systems than we have here. And why don't I hand it over to Curtis to explain that. There's a type of telescope that in the very high energy gamma ray world, they're looking for gamma rays coming from space. They have similar systems that we have that I sort of learned after I built our system. And there's a lot of overlap in the electronics. The one that I build is somewhat of a pure system that does all the triggering and

digital filtering of the signals coming in inside the FPGA, whereas the gamma-ray telescope electronics, they have external parts, analog digital converters that do some of the conversion and filtering of these signals. I've got to ask you one more question. So here we are with this incredibly advanced technology, what we used to call solid state, and yet your detectors are still tubes, photomultiplier tubes. Why? Well, they're very good. First of all, they can detect single photons, and they're very high speed. And one of the things we're looking for are very fast flashes of light. So we want as high speed sensor as possible. Most of the world is analog. And when high speed digital

electronics go so fast, you know, they don't look digital anymore. They look like analog signals. So just because they're analog doesn't mean they're bad. Okay. Let me just add, you talk about tubes and you're sort of, people bring up this image of these glowing things in old radios. These tubes don't have any filament. These tubes in some sense are electron manipulators. They convert the photon into an electron at the front surface. They accelerate it with a bunch of electrodes, and then it smashes into an anode, at which point it's converted into an electrical signal and goes through amplifiers and into this digital

processing system. So in some sense, this is not vacuum tube electronics. This is totally sexy electron multiplication without the intervention of noisy silicon. It does sound far more impressive than those things I used to pick up at the supermarket when I was eight or nine years old and stick in the back of our old TV. I'm dating myself. Curtis, just one more question. You did not, with all of this work with Paul in his lab there at Harvard, you did not have, shall we say, a traditional upbringing in advanced electronics. Has this served you well?

Oh, definitely. I am wonderfully thankful to Paul for giving me such a great education mentorship in electronics. And without his help, I definitely wouldn't be as successful as I am. Paul, you hardly seem like a retired person, but you are listed as emeritus now on the Harvard website. I sure hope that you will keep this work up, and thank you for not only what you're doing with Optical

SETI and before that good old-fashioned Radio SETI, but for also introducing these terrific younger guys to our world, where they're all off doing other things now, even as Curtis continues with this search for extraterrestrial intelligence.

Thanks a lot. I must say that, you know, one thing that keeps us professors young is having these wonderful, enthusiastic students come through. And we look much younger than we are because of their enthusiasm. Gentlemen, we're out of time. Thank you so much. Keep up the great work and as I usually say at the end of these. Thank you so much. Keep up the great work. And as I

usually say at the end of these conversations, you will call us when you get that signal from ET, right? Yeah, yeah. You'll definitely hear about it. Yeah, thank you. I don't want to violate any protocols here, but I also don't want anybody, I don't want the Associated Press breaking this story. Anyway, thank you, gentlemen. It's a pleasure, and I am thrilled that you guys are continuing the search for all of us here on Earth. We've been talking to Paul Horowitz, who is, I said it already, he's Professor Emeritus at Harvard University, but it's hard to tell from all the stuff he's still doing, not just with this, but with his lab.

Paul, by the way, how's that third edition of The Art of Electronics coming along? I hear it may be available soon. I'll get right back to it when I'm off this call. I was doing it just before our call. We expect publication of it in the year called 2014. Okay. Paul, he literally co-wrote the book on electronics. Curtis, thank you again so much for joining us and best of luck with what you're doing out here on the West Coast now.

Oh, thanks a lot, Matt. We're going to go to that colleague I mentioned a few minutes ago, Bruce Betts. It's time for his weekly update on What's Up in the Night Sky. That's just moments away. Well, what a disappointment. Not that I'm going to be talking to Bruce, but that we can't get Skype to work properly. This happens now and then. So on the phone line is Bruce Betts, the director of Projects for the Planetary Society. Hello. Hello. Hello. What means phone line? Do you read me over? Roger, read you five by five. All right. Five by five. Tell me what's up in the night sky. Venus. Stunning. Check it out if you don't every evening because it's just

super bright and it will go away eventually and go hide somewhere. But right now, looking lovely, Wednesday, November 6th, it's near the crescent moon. Also a couple days before and after, they'll be in similar parts of the sky. Mars up in the pre-dawn in the east or coming up around 2, 3 in the morning. There you can look for a similarly bright Regulus, the star Regulus looking much bluer than the very red Mars, but similar in brightness. And we've got Jupiter coming up around 11 midnight over in the east looking really bright and faboo.

This week in space history. In 1934, Planetary Society co-founder Carl Sagan was born. 2005, Venus Express was launched, and so I dug up a little random space fact for it that we'll get to in just a moment. Oh, great, and I'd forgotten that we were getting close to what a lot of people call Sagan Day. We celebrated that with a live webcast last year. Yeah, and there are various other celebrations going on this year, and we've got Casey Dreyer here is watching the original Cosmos every week and having parties and comments online.

So check that out if you're interested and want to join in the fun. Yeah, thank you for bringing that up. I talked with him about that last week, but it's worth mentioning again. Okay, let's see how this sounds over the phone. We move on to random space fact. Sounds boring over the phone.

Do it one more time. We'll do it right. Random space fact! Okay, I don't know if Ma Bell was up to that, but what the heck? So a paper published in August of 2013 used nearly half a million wind vector, meaning speed and direction measurements, from Venus Express to analyze winds and atmospheric circulation on Venus. That's a lot of what Venus Express does, is studying that big, funky Venusian atmosphere. You can check out more information on that.

Emily had a blog in August talking in more detail about what they've found. Man, that's quite a database, half a million. Yeah, years and years of observations of the circulation of the Venusian atmosphere. Well, go Venus Express and European Space Agency. Nice work. Yep, still going. We're going to run out of fuel at some point in the not-too-distant future, but still grooving right now. All right, we move on to the trivia contest. I asked you to name the four known inner moons of Jupiter, all of which revolve around Jupiter in less than one Earth day, and all of which are interior to the Large Galilean Satellite.

How did we do, Matt? We've really been getting a big response the last few weeks to the show. Of course, we've learned that there are a lot of people downloading the show from our archive. They're listening to lots and lots of past planetary radio shows. So I don't know, maybe they heard all those other people win beautiful planetary radio T-shirts, and they want to get in on it. Regardless of that, I'm going to let you mention the names of these four moons, because I don't think I could pronounce them correctly.

Oh, I'm sure I can't, so I'll go ahead. I could pronounce them correctly. Oh, I'm sure I can't, so I'll go ahead. Metis, and Metis is impressive. It orbits Jupiter in seven hours. Wow. That's a seven-hour period. And then getting slightly longer, going out Adrastia, Amalthea, and Phoebe.

And we heard from a number of people who said that, well, Amalthea was discovered way back in 1892 by E.E. Barnard. And I wonder if that's the same guy, you know, of Barnard's Star. But the other three, not until Voyager in 1979. Yeah, Amalthea is much bigger than the other beasts, probably has, may have a different origin history. So it's bigger and brighter, and that's why it got found first from the ground. Our winner this week, first-timer, Michael Cassavant. Michael Cassavant of Livonia, Georgia. And he indeed came up with the names of all four of those moons, so we're going to send him that stylish Planetary Radio t-shirt.

I just want to mention one other person. Interesting observation here from Douglas Cunningham. He says that the inner two orbit faster than the Jovian day. So if you could stand on Jupiter's surface, that is, if it had a surface, they'd be seen moving from west to east. Retrograde, right? Retrograde. Yes, indeed. I love that word. Retrograde by Remco. All right. So how can somebody win a shirt next time? Tell us. What are the craters on the asteroid Gaspera named after?

What are the craters on the asteroid Gaspera named after? Go to planetary.org slash radio contest. It just kind of tickled me. But let us know. Gaspar, you need to get us this answer by Monday, November 11 at 2 p.m. Pacific time. All right, everybody, go out there, look up the night sky and think about your favorite way to communicate via phone or pseudophone. Thank you. Good night. You know, I actually had a discussion with some people who did not believe that you could use tin cans and a string to communicate,

and I said, it absolutely works, and it probably sounds better than this connection. Next time. We only have to run it, what, like 40 miles. We'll be fine. About that. He's Bruce Betts, the director of Projects for the Planetary Society, and he joins us every week here via Tin Can on What's Up. Space Up LA, that's next time on Planetary Radio,

which is produced by the Planetary Society in Pasadena, California, and is made possible by the laser-sharp members of the Planetary Society. Clear skies.