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| Professor Dan Werthimer with the SERENDIP IV system at Arecibo. Photograph Copyright Ron Hipschman. | ||||
SETI (the Search for Extra-Terrestrial Intelligence) doesn't just end with the efforts of the SETI Institute. There are many other organizations that are contributing to the search, including the Planetary Society and various universities around the world.
Among these are the University of California, Berkeley's SERENDIP IV programme, and the SETI@Home distributed computing project, both of which are headed up by Professor Dan Werthimer. We managed to get an interview with Professor Werthimer about some of the project's he's working on currently.
Adrian Hon spoke to Professor Dan Werthimer, SERENDIP Project Director and SETI@Home Chief Scientist.
Astrobiology: How much help do you think the SETI@Home project has been to the SETI project?
Prof. Werthimer: It's made our search about ten times more sensitive and allowed us to search for a much wider variety of signal types. It's the largest supercomputer on the planet, with 2 million participants in 226 countries. So far the participants have donated 300,000 years of computing time. It has capabilities to grow immensely as people get faster and faster computers and phone lines gradually change to cable and fibre-optic. It's also getting people interested in SETI as they participate in a global science project.
The SETI@Home distibuted computing project has attracted over 2 million participants in 226 countries. Users download the SETI@Home screensaver, pictured right, which then processes data taken from the Arecibo radio telescope. Once the screensaver has processed all of a particular 'block' of data, the results are uploaded back to the SETI@Home central database and then downloads more raw data to process. So far, 300,000 years of computing time have been devoted to the project.
"[SETI] is limited by computing power - it's computers that do the listening, not Jodie Foster with headphones."
Astrobiology: What do you think the future of SETI is in this century? What kind of technological advances do you expect will increase the chances of contacting alien life?
Prof. Werthimer: We are still just scratching the surface in SETI, still only looking at small parts of the radio band. But the good news is that the technology is growing fast (it's limited by computing power - it's the computers that do the listening, not Jodie Foster with headphones) - 20 years ago we listened to 100 channels - now we listen to 100 million. We still need another factor of a million or a billion improvement, but that's only 20 or 30 years away.
Bigger telescopes are coming on line too. We are working on a project that will eventually be the equivalent of 100 Arecibo telescopes. (See your 1hT question below about the Rapid Prototype Array).
In a couple of decades we will be able to use a space based telescope to analyse the atmosphere of a distant planet orbiting another star - we'll find out if there's oxygen (indicating photosynthesis) or ozone or smog, so we can find primitive life - we won't just be limited to searching for radio or laser technology like we are now.
Astrobiology: What are the advantages of optical SETI over traditional radio SETI? There are those who say that civilizations will only use radio for communications for a short period of time, and then switch to terrestrial optical-based communication.
Prof. Werthimer: Optical SETI is good for point-to-point high bandwidth interstellar communication. For example, optical is good for someone who wants to talk to us and points a laser transmitter deliberately in our direction.
It's unlikely that we would find a laser pointed our way by accident, but we might find a radio transmitter that leaves their planet by accident, similar to our TV, FM radio, radar (these all go off into space - 'I Love Lucy' has gone by about 10,000 stars). These signals go off in all directions.
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| Scientists will use the Rapid Prototype Array unveiled on April 19th 2000 as a testbed for solving a variety of scientific and technical challenges as they move toward the final design and construction of the full One Hectare Telescope (1hT). The complete array is slated to become operational in 2005.
Photograph courtesy of Seth Shostak/SETI Institute |
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Astrobiology: Are you involved personally with the development of the SETI's Rapid Prototype Array and the forthcoming One Hectare Telescope (1hT)?
Prof. Werthimer: Yes.
Astrobiology: So do you believe that projects like this, rather than telescopes in orbit, are the way forward for SETI?
Prof. Werthimer: Yes. Earth based observations are vastly cheaper than space based telescopes. We should do the cheap experiments first.
Astrobiology: What's your opinion on the use of 'active SETI' - that is, actively broadcasting signals to other stars? Surely if all the stars are listening but no-one's broadcasting we'll never hear anyone?
Prof. Werthimer: We are a primitive civilization - we've only had radio 100 years in our 4 billion year history of life on earth. Some civilizations are going to be a few billion years ahead of us. Let's listen for a while and see what we can learn. If we don't hear anything in a few hundred years, let's think about transmitting. Who should speak for earth? What should we say? The decision should be made by all of humanity. (but of course, we are already transmitting radio and TV and radio out into space and have been doing that for 50 years).
"If you're interested in SETI, study science, especially physics, astronomy, maths and computers."
Astrobiology: How did you first become interested in astronomy and SETI? What would you say to a student who was interested in SETI - what sort of path should they pursue?
Prof. Werthimer: When I was a kid I built a huge telescope and read books by [Carl] Sagan and [Isaac] Asimov. In high school I joined the home brew computer club - a bunch of kids building microcomputers in our garages. My friends in that club became filthy rich (Steve Wozniak and Steve Jobs, two of the members in that club, started Apple...), but I started thinking about how to use microcomputers for SETI and remained relatively poor.
This is the best path for kids interested in SETI: study science, especially physics, astronomy, and math, and learn how to program computers.
| Internal Links | External Links | |||||||
The SETI Project Finding extra-terrestrial life Interview with Dr. Yvan Dutil (communicating with alien life) |
SETI@Home http://www.setiathome.ssl.berkeley.edu/ The SERENDIP Project The SETI Institute Optical SETI at University of California, Berkeley |
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