Night Lights: Interview with Woody Sullivan
For University of Washington Professor, Woody Sullivan, his vitae is both deep and broad. Self-described as an ETI Searcher, Gnomonicist, Outfielder, Scrabbler, Cyclist, Wordsmith, Quinquagenarian, Sublunarian–Sullivan has something to offer on topics ranging from how to build a first-rate sundial for a Seattle mall or another planet, to how to think about the electromagnetic SETI signals that our own planet is broadcasting, or leaking.
For instance, when Seattle computer scientist David Gedye first wondered what could be done with a huge network of home computers tied together with a screensaver, the hugely successful SETI@home project took shape. The guy Gedye went to for information about SETI and how to organize the project from scratch was Woody Sullivan. Five years after its launch, each day the SETI@home network contributes about one thousand years of equivalent computer processing time to the analysis of radio data.
Indeed, SETI strategies have occupied Sullivan for nearly a quarter-century. From his years in designing SETI strategies, Sullivan thinks what Hollywood did with Carl Sagan‘s book, "Contact", particularly the first half, is about as close as a popular film can get to what it’s like to do real SETI research. Much of the opening sequence owes a debt to Sullivan, since he spearheaded the scientific understanding that the Earth is leaking electromagnetic signals all the time, mainly from TV and some military radars. Just as the film, "Contact", begins, the viewer is taken on a voyage, as if riding such a signal from the depths of the universe until it zooms back towards Earth. Before Sullivan’s work, previous SETI strategists more often thought of broadcast sources from another civilization as likely to be directed beacons, or singularly devoted transmitters. Instead Sullivan supposed a viewpoint about the more constant background noise, one that unavoidably might date back to the film’s key plot-point when the advanced civilization finds the first terrestrial TV broadcast–the carrier signal when Adolf Hitler hauntingly introduced the 1936 Olympic Games in Berlin. "These are not great examples of our civilization," said Sullivan.
|The Sullivan sundial designed for the Physics and Astronomy Building, University of Washington, Seattle.|
To say Sullivan’s interests are unconventional or eclectic however is perhaps not to capture the wide-range of projects that his career has spearheaded; his participation in astronomy has been both a mile-wide and a mile-deep, a combination which astrobiologists can tell you is exactly what it takes to handle research in his newest chosen field. "The fundamental question of the existence of extraterrestrial life is not new, but for the first time we can now carry out scientific experiments and observations to search for such life," writes Sullivan.
In a way, each of his talents has been a good preparation for understanding a terrestrial future in which life might be detected elsewhere: patience and longevity (quinquagenarian), deciphering of signals (scrabbler), instrument building and engineering (gnomonicist and cyclist) and even some measure of luck (outfielder). For those less adept at wordsmithing than Professor Sullivan, the translation of his vitae has to do with the following facts about him. He is over fifty, a searcher for extraterrestrial intelligence (ETI), a designer of scientific instruments, including a number of landmark Seattle sundials (gnomonicist), a player of the game Scrabble, a bicyclist and baseball outfielder, and through his research in radio astronomy, is interested in probing the lunar interior with radar. To sum up his approach, he is fond of quoting Mark Twain, "We had the sky up there, all speckled with stars, and we used to lay on our backs and look up at them and discuss about whether they were made or only just happened."
Astrobiology Magazine had the opportunity to talk with Woody Sullivan about some of his eclectic interests in a wide-ranging way, including his role in making possible such landmark projects as the Mars’ sundials, the SETI@home screensavers, and his now famous posters, "Earth At Night".
Astrobiology Magazine (AM): You are a sundial enthusiast, or gnomonicist. Your participation in the Mars’ sundial project is part of their January 2004 landings. You were described by Bill Nye ("the Science Guy") as key to making their design possible for the first interplanetary sundials. How did you first get interested in sundials?
Professor Woodruff Sullivan (WS): It came about from the building we’re in. Since 1994, we have been in the Physics and Astronomy Building. I got a request to design the architectural dials for the building, and it started from there. I am very interested in the history of science. The architects liked the design. I spent around 6 person-months, in designing the dial, so it was a big project. I tried to make something that was in the long tradition of sundials, one that wouldn’t need maintenance for 50 years. The University of Washington sundial is a well-known thing on campus, and in Seattle.
|Mars Sundial and color test calibration target for the Mars PanCam, the panoramic camera. Click image for larger view.|
AM: I thought the Sun didn’t shine in Seattle?
WS: That is why we appreciate the sun when it’s out. I want to make Seattle the sundial capital of the world. My sundial phase has really been in the last decade.
By dial projects, I mean big public displays. In high schools, in parks, in malls. Each one is unique. These are not just a plate with a triangle on top. Working with architects, scientists, construction workers, those people are a real kick to work with.
Bill Nye got into sundials via his father originally. Bill and I saw our common interest in sundials. When he came up with the calibration target on the Mars rover, he thought of me. He asked me if I wanted to put a sundial on Mars.
I answered immediately in email: Are you kidding? Is the Pope Catholic? Does Ken Griffey play centerfield for the Seattle Mariners (true at the time)? Does it rain in Seattle? So we got started.
In the summer of 1999, it all had to be designed in 6 months. We madly pushed emails back and forth. We also wanted to make it look good. Over six months, we turned it into a sundial. We were able to fabricate the sundials in our shop at the University of Washington. I got our scientific instrument maker, who worked on the big dial on the Physics and Astronomy building. He designed the dials in their details.
We had to get NASA and the Jet Propulsion Lab to approve the epoxy. We had anodize the metal. We had to glue in the silicone rubber, which attaches the rings and color patches. It all had to be color-calibrated. This was all very interesting to me–to make something that would rest on another planet.
And fortunately, except for a very few high, thin clouds, most days on Mars are sunny.
AM: What are the unique challenges of putting a sundial on a Mars’ rover, either because the shadows are not intuitive or the platform itself is moving in direction all the time?
WS: It wasn’t originally a design that was meant to be read on a moving platform. The 2001 Mars mission was to be a home station, and the rover would go out from that home. The Pan camera was on the home, and it was stationery.
|Night sky observations compete with urbanization and street lights|
About three months into the sundial design, the mission was cancelled. That threw everything up in the air. NASA said: "We are going to have the community bid on a 2003 mission".
The Cornell people were again selected for the 2003 mission. NASA didn’t feel confident in a retro-rocket landing, and went back to a bounce landing, as it was successful on the 1997 Mars Pathfinder. The Cornell people said they would use the same calibration target. So we changed the plate to read: 2004.
But we had the big problem: a sundial on a moving vehicle. How do you know how the vehicle is oriented? We have now, because of this history, a sundial on a moving vehicle.
We have to get the orientation from NASA. But NASA is going to get the vehicle’s orientation by pointing the Pancam to find the sun in the martian sky. So ironically, they are going to use some of the same information that the sundial relies on for its shadow. Knowing the time, and seeing the shadow, we can find the same orientation.
|A simulated image of the Mars rover carrying the Athena science instruments against the horizon of the Mars rust-colored sky. As Cornell’s Project Scientist, Steven Squyres, wrote about their simulations: "We’ve just finished a ten-day test using the rover to simulate twenty martian days. The guys took their baby out to a site somewhere out in the American Southwest, and we drove it from JPL just like we’ll drive the real MER rovers when they’re on Mars. The "landing site" was fantastic, with no vegetation, great rocks, and many geologic puzzles for us to solve. Very Mars-like! In our twenty "sols" of operations, we drove the rover more than 200 meters, made a bunch of detailed measurements of the chemistry of the rocks, and took a lot of spectacular pictures."|
But still, what latitude is it going to be at? NASA said: "The landing site is going to be selected long after you have to deliver the dial". So we came up with superimposing the dials’ hour lines via the web.
Electronically we can change the selected lines and what they mean. Sundials can show about a dozen things other than just the hour or time of day, like what is the Martian zodiac? On the web, I wanted to let the users define their own units. How many hours do they want? Do they want a personal calendar? We probably won’t have the money to do the website that way, but I liked the whole idea of spreading the sundial gospel. It is a great way to get people to think about their place in the cosmos.
It gets people thinking. How does a sundial work on earth? How will it keep on time on another planet?
The whole idea of it was great, as an educational project. There is a plan to do a movie about the Mars Dial. The idea is to take an image every 10 minutes, for fifty or so images, and show the passage of time in a dramatic way.
AM: You are planning a terrestrial counterpart to what is happening on Mars, called The Earth Dial?
WS: The idea of The Earth Dial is to do it in conjunction with the Mars’ dials, with Bill Nye. This is something I’ve wanted to do for seven or eight years. The idea is set up dials all over the world, put webcams on them. Look at all these different sun dials at different longitudes on a single web page. You would get a palpable sense of time around the globe.
You could follow the Earth’s terminator, the night-day line, as it moves. The different latitudes would give you different patterns. The one in Sydney will look different from Seattle. They will all indicate the same time at the same longitude.
We are in the mad-throws, because at the end of this month, we will have the first Earth Dial instructions on the planetary society website. It is fairly specific, like all of them will be an eighty centimeter diameter circle. Like the Mars dials, the motto will be "Two Worlds, One Sun", which is a very nice motto. They will all read 2004. But we also want the local language on the Earth dials. You put the name of your town and country.
So while they will all be the same–a post and ball on the end–the outer two rings will be evocative of the Mars’ dials. On the circumference, or outer edges, they can do whatever they want. They can put whatever they want there. For instance, they can put individual artwork and languages, like Swahili or whatever.
The Earth Dials will each have individuality. We have no idea how many we can solicit. We hope we will have several dozen. And a distribution around the globe. You never know. I was involved in SETI@home, and we never anticipated how popular that would become. The Earth Dials require more work than just downloading a screensaver, but you never know.
The Earth Dials will run for six months, while the rovers will collect their own data. It is a coat-tail project to the Mars Dial. The Earth Dial homepage will be on the planetary society website, by early November.
AM: There is great scientific curiousity about how the atmospheric conditions on Mars might appear on camera. Lunar astronauts described the moon’s shadow, not distorted by an atmosphere, as distinct and somewhat disorienting. Most films from Hollywood have a distinct red filter quality that is akin to wearing rose-colored glasses. How does one approach such a description of what the orange-pink corrections will actually look like in advance?
WS: By "true colors", what does one mean by true? Do you mean what you would see on Mars? Or the scientific plot of intensity vs. wavelength?
The scattered light from various molecules and dust particles influence the colors that you would see. Not as it would appear in a vacuum. It has a blue or grey cast on Earth because of scattering. Even the Earth shadows are not black, but more bluish. So first, you need to correct for scattering on Mars. Ultimately you want to find what kinds of rocks are on Mars, so you want to see their colors as they would appear in a laboratory.
On the calibration targets, you look at those color scales on the Earth, as we calibrated their known values before launch, and then adjust the picture hue and tint to compensate for the local martian atmosphere or weather. The point is after taking the science data, of intensity vs. wavelength, a skilled person could translate that to what a human eye could see.
AM: You have also been working in SETI fields for some time, correct?
WS: Why am I so involved in astrobiology these days? I am trained in radio astronomy over the decades. Interstellar molecules, those kinds of studies. I got interested in SETI about 25 years ago. I have eclectic interests. Here was a fascinating field.
Within the SETI community, I got people to think about the leaking radiation from the Earth. Most SETI was set up mainly to look at beacons from another civilization. But we don’t have a devoted beacon broadcasting from Earth even. A priori, we don’t know that a civilization would set up a beacon. But we Earthlings are leaking all the time, just from our daily activities.
|The first TV transmission from Earth, the 1936 Berlin games, and now the farthest strong signal from an electromagnetically-leaking planet. Because of the Second World War these were to be the last Olympics until 1948. "These are not great examples of our civilization." -Woody Sullivan|
Credit: National Archives, USHMM Photo Archives
So what are the sources of leaking radiation that could most easily detected. Military radar, and TV. These are not great examples of our civilization. I call this eavesdropping. Sometimes when you eavesdrop, you get a better idea of what is really going on, say at a party. So when another civilization is eavesdropping on us, they may actually get a better idea about what is going on with Earth.
There is more to Earth, as a planet, than what we could send on the gold record that travelled on the Voyager spacecraft. We, as a planet, are not just about listening to Chuck Berry.
AM: What are the signals that our planet’s civilization leaks now?
WS: I was looking for the best combination for a signal being picked up from 10 to 100 light years away. And bearing information. Military radar, called the Ballistic Military Early Warning System or BMEWS, is a very powerful broadcast, but carries no real information. There are a couple other strong radars on the planet. The strongest radar is Arecibo, but it covers a very tiny bit of sky. The odds that you were in that patch, or broadcast path, is unlikely.
So for a good signal for reception, you want to balance a trade-off between both powerful and broad-area beaming.
About information, the input is not actual TV programs in the broadcast signal. But I was talking first about the video carrier, which is a single frequency carrier. Your TV locks onto it. You can’t get the whole program information. From another planet, you could get alot or dozens of those carriers, about a rotating planet with doppler shifts. That communicates alot of information to a receiver.
So what you want to imagine about what signals we Earthlings are optimally leaking to our neighbors: it should be broadly spread, strong, and possibly discernable as an intelligent signal.
AM: You were instrumental in the now famous "Earth at Night" posters. How did this picture of urbanization from orbit become a personal interest?
WS: In Time magazine, I had seen a picture of how the United States looked at night from orbit.
So I asked: "Why hasn’t anyone put an entire image of the earth?" I put it together in the mid 1980′s. I published the poster.
The image itself is from the Pentagon’s weather satellite. The DMSP [Defense Meteorological Support System] is the satellite’s name. Every twelve hours you have a new image of all the earth.
I’ve been working on another addition. There is now better data, because the satellites are digital. Earth at Night II, is coming. This is also part of the my research historically, into what kinds of leaking radiation might help with SETI.
I have also been curious about, "how humans are affecting the earth?" As a card-carrying Sierra Club member, I was interested in resource use. After working on the original "Earth At Night" poster, I later became a leader in the light pollution issue and how it affects astronomy.
"Earth at Night" itself has nothing to do with SETI, because the sun is so much brighter and no civilization would first see a living planet because the lights are on. But if you were poking around in our solar system, you would see our presence from snapshots of light–the dark-light contrasts in our own nightside is a good signal of life.
AM: Do you have any reflections on the wild success of the SETI@home project? How do you feel about watching it evolve from the early SERENDIP project to more than 4.7 million computers?
WS: Through the 1980s, we, the SETI community, had a low-scale program. Finally in 1991, we got ten to fifteen million dollars from Congress, then just as suddenly, it was axed. We had the software and hardware ready to go, and it was great sadness to lose it.
|Arecibo. World’s largest dish, radio telescope. Puerto Rico.|
Then the screensaver idea behind SETI@home came on. SETI@home was the idea of a computer scientist, David Gedye, who didn’t know anything about SETI, but was an expert in distributed computing. Through a mutual friend, he came to me. At first, I was very skeptical. It is a very challenging problem, to push out radio data, process it locally, and keep track of everything that is going on.
Foremost, where are we going to get all the data? Most of my SETI activities, have been about optimizing strategy: when and where should you look for signals?
This is now 1995-96, and finally, SETI@home looked like it might fly. From the perspective of public outreach, you not only were getting CPU [computer processing unit] cycles, you also were getting people from all over the earth to participate, and it is such a great forum for teaching people about SETI.
So we started looking for scientific partners and sponsors. We looked at two groups of SETI researchers, and the ones in Berkeley, associated with the SERENDIP ("Search for Extraterrestrial Radio from Nearby Developed Populations") project, they were the best match. David Gedye, knew David Anderson [Gedye was a former computer science graduate student of Anderson's at Berkeley], and we started working with the Arecibo data.
For sponsors, we knocked on the door at Sun, Microsoft and some others. We had some possible deals. But mostly they were too commercial. Or wanted to work on UFO’s.
AM: So you started working more in the field of astrobiology?
WS: At that time, the University of Washington–we were just getting going with an astrobiology graduate course. This is where I’m devoting my time.
Astrobiology– including the Mars’ rock, the Europa ocean, the new planet discoveries, and the prospects for water on Mars–those findings all seemed to come together at once. We had a course in biological oceanography–called "Planets and Life"–with John Baross, and we had a lot of interest on campus. We got a National Science Foundation grant for graduate programs in astrobiology. As a student, you get a certificate in astrobiology. You get to do twenty-five percent more work than just your departmental degree, say, in microbiology, paleontology, or astronomy.
|Close-up of a Mars meteorite, showing what some have argued appears to be fossilized evidence of ancient microbial life.|
Image Credit: NASA
But mainly, leaving the program, you’re not afraid of collaborating with geologists, if you’re an astronomer, or an oceanographer, if you’re a microbiologist. I’ve always disliked the barriers in different departments. You can’t easily cross borders intellectually. Astrobiology crosses those boundaries. We are now one of the NASA Astrobiology Institute members. In the astrobiology certificate program, we have 15 graduate students. And 20 to 25 faculty in different departments.
John Baross and I are editing a graduate textbook called "Planets and Life" with Cambridge University Press. The idea of this textbook is "if I’ve heard about astrobiology, how to get the basic background". No matter what your background, if you have a bachelor’s degree, we will lay things out so you can get at least two-thirds of the material. We cover the whole field in 25 chapters. It is expected for a late 2004 publication.
AM: Chronologically, when do you demark the beginning of this field, astrobiology, for instance?
WS: I am a student of the history of science. In my research, I have looked at radio astronomy in particular, as it grew directly out of radar work during World War II. I’ve thought about how new discoveries have been made. There is something of the same feeling in the past seven years in astrobiology, as was going on in early radio astronomy.
And some of the same questions are being asked by astrobiologists: Should we have our own journals? Should we have our own societies? How do we communicate?
Unlike the link between radar and what became radio astronomy, this was not a single technology, nor was it developed for war purposes. Astrobiology instead is a confluence of new discoveries. Before astrobiology, there was exobiology and SETI. There were societies devoted to the Origins of Life for 40 years.
But with the Martian meteorite, while probably a wrong conclusion as an example of fossilized life–that publication gave a kick start to astrobiology . And now new research says the next one may be right–in theory, the solar system supports or is capable of carrying rocks between planets, like panspermia.
The next discovery was extrasolar planets. The reality of it raises tremendous excitement. The Kepler mission is really neat. If that one works, that is going to be fantastic. In five to six years, we may have a few dozen earths, or earth-like planets to look at.
|An illustration of the Kepler spacecraft.|
Image Credit: NASA/Ames
The third one is extremophiles. Over the last ten to twenty years, microbiologists have come to terms that there is far more than what they dreamt of in their philosophy. That gives more optimism to extremes as supporting life as perhaps we don’t even understand it terrestrially yet.
Then the happenings on Mars and Europa. Mars with liquid water on the surface. There is compelling evidence of liquid water even on the surface now, with these gullies. Europa’s ocean is a longer term prospect. That whole concept, changes the way we think about habitable zones.
For habitability, you need energy, time, the right chemical elements. But it doesn’t have to between around an earth-like orbit, say 0.9 to 1.1 astronomical units (AU). If you throw in radioactive heating, you could get further away. Our whole thinking about the cosmos, has really gone to a whole different level since the 1990s.
Amongst the pioneers in astrobiology, were the SETI community generally, the Viking project team, and the exobiologists. This also now has alot to do with life on earth. This has caught on with more ‘there’ there, because you are studying things right here on Earth. You’re not just dreaming about the possibilities.
Astrobiology is as much about life here.
For the future, Sullivan’s ‘to-do’ list is no short scientific shopping trip. He has plans for a second "Earth At Night" poster, the images of which have already been stitched together. Sullivan is co-editing with oceanographer John Baross, also of Seattle, a graduate text book for astrobiology in twenty-five chapters and planned for publication in late 2004.
From January to April of next year, two of his unique creative contributions will arrive and rove about on another planet. Each sundial is inscribed with the words "Two Worlds, One Sun" and bears the name "Mars" in 17 languages, including Bengali, Inuktituk, Lingala and Malay-Indonesian, as well as ancient Sumerian and Mayan. Four gold panels along the sides of the sundials are inscribed with stick-figure drawings of people [called 'sticksters'], as well as a message to future Mars explorers. To commemorate these first interplanetary sundials, he will help the Planetary Society tie together a large part of the Earth to view from one location, the passage of time simultaneously, and include a disperse set of webcams in their native languages and artistic cultures. Orbital projections of where the two NASA Mars Exploration Rovers (MER) are right now, can be continuously monitored over their half-year journeys.
Even a cursory glance at his "Earth At Night" view, must reveal at least one tiny, glowing dot along the northwest coast of the United States that is Sullivan’s office. Whether the weather in Seattle is cooperative or not with his plans for catching the sun’s shadow in the Pacific Northwest, Woody Sullivan may likely have a night light on for the foreseeable future.
Collaborators on the Mars Sundial project include:
* Bill Nye, a 1977 Cornell engineering graduate, Rhodes Class of ’56 Professor and host of the PBS show, "Bill Nye the Science Guy", and the upcoming "Eyes of Nye" television shows
* Steven Squyres, Cornell professor of astronomy and principal investigator for the Athena suite of science instruments carried by the rovers;
* Jim Bell, Cornell assistant professor of astronomy and lead researcher for the high-resolution stereo Pancams carried by both rovers;
* Woodruff "Woody" Sullivan, sundial enthusiast and professor of astronomy at the University of Washington;
* Tyler Nordgren, Cornell Ph.D. ’97, an artist and astronomer at the University of Redlands in California;
* Jon Lomberg, an artist and creative consultant to the Mauna Kea Center for Astronomy Education, University of Hawaii at Hilo;
* Louis Friedman, executive director of the Planetary Society.
JPL, a division of the California Institute of Technology, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Additional information about the project is available from JPL and from Cornell University, Ithaca, N.Y