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It looks like a giant ice cream cone, and it's normally at -200 C. In fact we thought of approaching an ice cream manufacturer for sponsorship. Whatever am I talking about? Why, the new feed system just built for Project Phoenix here at CSIRO in Sydney, Australia.
This system is one of the nice new spin-offs from SETI work. But it all started back in the mid-80s when CSIRO built the Australia Telescope (AT). To cover the wide frequency range of this telescope, Graeme James and friends developed a broadband waveguide-to-coaxial-cable converter (the bottom half of the "ice-cream cone"). When NASA was constructing its original SETI receivers, they found that if they used these converters they only needed two different sizes to cover the whole Targeted Search frequency range (1,000 to 3,000 Megahertz). So they asked CSIRO to build several of the converters and had planned to integrate them into separate low-noise receivers operating at temperatures below -200C.
When JPL dropped out of the picture, the SETI Institute asked us to assume the job of providing these cryogenic receivers. So we took the original converter and tweaked it some and found to our delight that one new converter will do the job of two old ones. Now we only have to build one cryogenic receiver to cover the whole frequency range. Good value!
The second part of this story (the top half of the "cone") is another example of a fruitful collaboration. The receiver we're building will initially be used on the Parkes radiotelescope which has only a prime focus. Feeds for this type of antenna are usually not designed to be broadband in frequency. The main problem is that as you increase the operating frequency, the pattern of illumination on the telescope surface gets narrower and the telescope loses efficiency. One would normally expect to use many feeds to cover the SETI frequency range — and they are big, expensive, and time consuming to change.
Phil Stanton of JPL came up with a smart idea: He took a high efficiency feed design developed in CSIRO by Bruce Thomas and added a dielectric insert along the centerline. This dielectric insert has the effect of compensating for the awkward narrowing of the feed pattern at higher frequencies. When chosen correctly, this produces a feed horn which keeps a constant illumination pattern over a wide band. Magic! So it looks like we will only need two sizes of these feed horns to cover the required range, and both receivers and feeds should be ready before the start of Project Phoenix observations.
Wellington is the Australian Coordinator for Project Phoenix.
Our Galaxy boasts 100 billion stars, spanning a range of sizes, chemical compositions, and ages that bracket the properties of our Sun. By every measure, the Sun is boringly ordinary.
However, one property of Sol remains undetected amongst its cousins: Planets have not been found encircling any other normal star. The news about three planets around a pulsar requires a qualification, as they must have formed by a different process than our nine planets, and will suffer radiation doses inhospitable to complex organic molecules. Frank Drake noted in the early 1960s that intelligent life would depend on the abundance of environmentally-benign planets. Sadly, astronomers have not yet found any planets orbiting normal stars.
This failure is not for lack of a method. During the middle decades of this century, astronomers realized that extra-solar planets could be most easily detected by looking for the tiny gravitational pull they would exert on their host star. The wobble of a star due to an orbiting planet can be compared to the motion of two embracing dancers twirling across the dance floor. Astronomers need merely apply standard Newtonian physics to determine the mass of invisible planets around wobbling visible stars. State-of-the-art wobblometers are based on the Doppler effect, which produces a change in the frequency of light as the star accelerates. This technique enables detection of Jupiter-sized planets around the nearest 100 stars, and the most active search has been made by a Canadian team led by Bruce Campbell and Gordon Walker.
Using the Canada-France-Hawaii 3.6 m telescope on Mauna Kea in Hawaii, they monitored 21 solar-like stars for 11 years. Shockingly, they have found no planets around any of them. They would have marginally detected planets having the mass of Jupiter and would have easily detected planets slightly more massive; super-Jupiters. In fact, for planets orbiting within one Earth-Sun distance around a star, they could have detected planets having half Jupiter's mass. At Lick Observatory, Paul Butler and I have been carrying out a parallel Doppler-based wobble project. Our data also show no planets around those same 21 stars.
Where are the super-Jupiters? Perhaps Jupiter looms above the planetary crowd in the Galaxy, assuming there is a planetary crowd. Or possibly the typical solar system is dominated by one planetary whopper, no larger than Jupiter, which just barely evades detection. Maybe Jupiter is a rare gargantuan planet with few peers, implying that our solar system formed under unusual conditions.
If Jupiter is simply "tied for first place" among the galactic planets, then we must improve the Doppler wobble technique so that its planetary brethren can also be detected. To do so, Paul Butler and I are initiating a next generation search, capable of detecting planets of Saturn mass. The project has already begun at both Lick Observatory and at the Keck Observatory 10 m telescope, the world's largest. The two telescopes have recently been outfitted with spectrometers that analyze the entire visible spectrum, blue to red, in exquisite detail. Starlight is broken into 60,000 individual wavelengths, permitting detailed measurement of the tiny Doppler shifts caused by Saturnian-mass planets tugging on a star.
Within the next three years, we expect to detect planets, should they exist, and learn about their masses and orbits. Of course, as soon as a planet is found orbiting any star, it will serve as a prime SETI target. Our planet search also contains many widely-separated double stars that also would be ideal targets for SETI. Double stars may harbor extended civilizations around each star, necessitating energetic radio communication between them (unless their cable TV companies have strung up interstellar wires!). In any case, successful detection of extra-solar planets will greatly shrink the radio wave haystack within which to search for needles of intelligent life.
Marcy works at San Francisco State University and the University of California, Berkeley.
As you read this, the hi-tech receiver to be used by the most ambitious SETI experiment ever undertaken is heaving across the watery expanses of the Pacific. The 28 million channel receiver, packaged in a truck trailer and loaded aboard ship, is scheduled to start analyzing cosmic static at the end of January. Once hooked to the Parkes 64 m radio telescope in Australia, the Phoenix receiver will spend a half-year scrutinizing 200 southern hemisphere stellar systems.
These are facts that I know well, and repeat frequently. Undeniably, familiarity has robbed them of power and context. I was therefore unprepared for a mild epiphany when David Packard, one of Project Phoenix's principal benefactors, came for a hardware demonstration just before Thanksgiving.
The demo was straightforward: A weak signal was deliberately injected into the receiver, and the analysis software, like a trained dog, was asked to fetch it. In a darkened room, a half-dozen engineers and scientists crowded behind Mr. Packard as he stared at the receiver's computer display. It took several minutes before a faint, yet insistent diagonal line slowly appeared in the sea of noise filling the display. The crowd was pleased. But I was blown away. Suddenly, I could imagine this. I could see it happening, not here on a lab bench, but in the Australian countryside.
A test signal, yes. But this experiment was no longer just well-worn words. It was a palpable reality.
To accelerate an object, you have to apply a force. As it moves, you do work on the object. A pitcher must apply force and do work to hurl a baseball. The baseball gives up this energy when stopped; for example, it can smash a window. So we think of this energy as being carried by the ball from the pitcher's arm to the window. We call it kinetic energy — the energy of motion. It is equal to half the mass of the object times the square of its velocity. If your car weighs two tons (2,000 kilograms), then at 60 miles per hour (88 feet or 26.8 meters/second) it will have (2000)(26.83)2 or 720,000 Joules of kinetic energy. This is 0.2 kilowatt hour (costing 2 cents from your local power company), and is enough to smash the car and kill the driver.
But now consider a 4,000 ton spaceship going at the speed needed to reach the nearest star, Alpha Centauri, 4.4 light-years away, and return before the astronauts reach retirement. It must travel at 0.2c — two-tenths the speed of light — or over 37,200 miles per second. This is 5,360 times the escape velocity from Earth, and is enough to launch the ship from our planet (5,360)2 or 28 million times. Its kinetic energy at that speed is 2 quadrillion kilowatt hours or about 20 years of total world energy consumption.
In addition, to stop there, return, and stop here, means four velocity increments of 0.2c each, and would require 16 times the above energy, or 800 years of total world energy usage. We must supply at least this much energy. Actually, because our engines aren't 100% efficient, we must supply a great deal more. We think the price of interstellar travel is out of reach. We think SETI is the only way we will ever make contact. The same is true for ET's. Will we be ready when they call?
Oliver is the Senior Technical Advisor for Project Phoenix.
On the 15th of December, Project Phoenix equipment will set sail from Oakland aboard the Direct Kiwi, bound for Sydney harbor and thence to Parkes Observatory on or about January 10th. Due to the unexpected replacement of a main bearing in the 64 m antenna, our observations at Parkes have been delayed by two weeks at the request of our Australian colleagues. SETI observations will begin on January 30th and continue through May 30th (subject to change in the event of a signal detection!). These observations will be followed by a two week period of "Cooperative Science" during which Phoenix scientists will collaborate with Australian scientists using all, or part, of our systems to conduct additional SETI or radio astronomical observations.
The past 12 months have been exciting. Our engineering team received the original High Resolution Microwave Survey equipment on a long-term loan from NASA. They then proceeded to redesign parts of it to improve reliability, doubled the number of channels, added two more detection subsystems for long distance interferometric verification, built two new RF/IF systems for Parkes and Mopra and made our control software smart enough to handle all the extra gear. Meanwhile, under contract with the SETI Institute, our Australian colleagues have been busy as well. They have built two new, innovative feed horns and a very wide band, cryogenic receiver covering 1 to 3 GHz for use at Parkes and later at other prime-focus antennas. The Australian front-ends have already been tested in the lab, and at about the time the Direct Kiwi sails from Oakland, they will be mated with the down converter built by the Phoenix team. The system will then be tested on the Parkes telescope to measure the final noise figure.
Todd Henry and Dave Soderblom at the Hubble Space Telescope Science Institute and Dave Latham at the Harvard-Smithsonian Center for Astrophysics have been collaborating with us to produce a prioritized list of target stars for this southern observing campaign. These stars are all solar-type, at least 3 billion years old, and have no nearby stellar companions that might disrupt planetary orbits. They lie at declinations below -35 degrees, and therefore can only be observed from the south. Gary Heiligman has also added a band of stars near -6 degrees declination to the list. When viewed from northern latitude antennas, this band of stars falls behind the orbits of the geosynchronous satellites and is therefore subject to a lot of interference, but from Parkes, parallax shifts these stars about 12 degrees away from geosynchronous orbits.
In spite of the hectic pace of the past few months, we took some time out last week for a photo opportunity (see page 8) in our new Project Phoenix tee-shirts! They feature our logo (p. 8) which was designed by Lynn Beckley, a graphic artist working for Hewlett-Packard. The logo shows two planetary systems: one our own, and the other somewhere in the vast darkness of space, but between them there is a single point of contact. It is also true that you can see the head of a Phoenix in the logo, too — that is, if you think a Phoenix looks like a toucan!
Tarter is Project Scientist for Project Phoenix.
On Thursday 27 October, the first Australian workshop on SETI and Society was held in Sydney, hosted by CSIRO's Australia Telescope National Facility (ATNF) and the University of Western Sydney, Macarthur (UWS, Macarthur).
Why these groups? The ATNF operates both Parkes and Mopra, the telescope sites for Project Phoenix's imminent observations. And UWS, Macarthur is home to Dr. Bobbie Vaile, one of the Australian proponents of SETI, and a "non-CSIRO" official Phoenix observer.
Why the workshop? Australia needed to initiate national thinking on SETI and society in view of upcoming events. After all, what if there is a SETI detection in Oz (Australia) in early 1995? We needed a broader awareness of the consequences. So we rounded up a diverse group of thirty professionals, and put them together to discuss new information, controversial ideas, and imaginative hypotheses. Some of the subject matter included the following:
Ray Norris, the ATNF Head of Astrophysics, began by describing the characteristics of radio searches and the Project Phoenix plan. Then Don McLean, of CSIRO radiophysics, played devil's advocate by raising the familiar argument that the absence of Von Neumann probes suggests an absence of intelligent extraterrestrial life. Peter Slezak, a cognitive scientist, responded that the mind of an alien intelligence would be so different from our own that it would defy our understanding.
The discussion proceeded from uncertainty to pessimism. Jon Ables noted the noise-like appearance of signals as they begin to approach the Shannon limit for communication channels. The implication is that we would be unlikely to recognize a sophisticated signal as anything other than noise, and that even if we did we wouldn't be able to decode it.
Bobbie Vaile made a more upbeat statement, describing the great success of incorporating SETI into one of her university's first year science course. The course has been wildly over-enrolled.
ETI in film and literature were also on the agenda. Roslynn Haynes, a professor of English literature, grouped fictional accounts of encounters with extraterrestrials into two main categories: invasion of Earth, or the discovery of morally superior beings. This theme of ETI as angels or monsters was taken up by Nick Stathopoulos, an illustrator. He presented a series of depictions of aliens, all with anthropomorphic characteristics, and suggested that a real ETI would lie beyond our imagination.
Finally, a magazine journalist, Wilson da Silva, discoursed on the great media feeding frenzy that would take place in the event of an ETI detection. But he suggested the discovery would lack the one element required to cement it into popular consciousness — an iconic image.
The viewpoints were diverse, but the enthusiasm was unanimous.
Sim is Public Relations Manager for the ATNF.
"How come they didn't have activities like this when I was in school?" is a question I hear frequently when discussing or conducting workshops on the Life in the Universe teacher's guides. I usually explain that — while it may be too late for you to enjoy the exciting, hands-on lessons described in this new curriculum — it's not too late for the children in your life.
The Life in the Universe series was designed by a team of educators and scientists during two summer workshops held at the SETI Institute. Further development and refinement were the work of project staff, also housed at the Institute. Funds for the three-year curriculum project were provided by the National Science Foundation and NASA, and collaborators included the Lawrence Hall of Science, San Francisco State University, and Evergreen State College.
The products of this cooperative effort include six teacher's guides. In The Science Detectives, third and fourth grade students follow the exploits of Amelia Spacehart as she races about the solar system. To discover where Spacehart is going, students must study the features and mechanics of our solar system. Fifth and sixth graders model the evolution of a planetary system and a planet capable of supporting life, study life's evolution and develop a life form that is biologically plausible, and simulate the evolution of intelligence and culture in the SETI Academy Planet Project, a three volume series of activities. Middle school students study the characteristics of life and design experiments to detect biological activity in Life Here? There? Elsewhere? They can also explore the possibilities for uncovering life in our galaxy in Project Haystack. Each guide comes with ancillary materials, such as posters, video tapes, color transparencies, and activity cards.
The Life in the Universe series has been highly rated by the teachers and students who tested and evaluated it. It appears that the guides are as fun to use as they were to design and write, and SETI has proven to be an excellent hook to get young folks interested in science.
The series will be available in the spring and fall of 1995 from the Colorado publishing house, Teacher Ideas Press, a division of Libraries Unlimited.
Stoneburner is Curriculum Development Manager at the SETI Institute.
Leonard Nimoy, better known to millions as the logical Vulcan in "Star Trek," paid a visit to the SETI Institute in September. Mr. Nimoy was interested in hearing some of the scientific and engineering background of Project Phoenix in connection with a new entertainment product he is currently producing. He and Frank Drake pose here for an impertinent camera.
(Picture to be added here.)
The Institute has been very busy since the last newsletter. Our many projects continue on course, and Project Phoenix activity is reaching a crescendo as deployment nears.
Major facility changes have been occurring! In order to accommodate Project Phoenix team members in their new permanent home on the first floor, immediately below the Institute administrative and education program offices, we have doubled our square footage under lease and installed new LAN and phone systems. During this transition, we have had intermittent failures of our Internet connection, so let me apologize to any of you who may have experienced delays in reaching us.
Late last month we were visited by another of our major donors, David Packard. Mr. Packard had an opportunity to see a demonstration of the nearly completed Phoenix signal detection system. This demonstration included finding a drifting CW signal 3 dB below the noise power in a 1 Hz band, one of the key tests of the revised system. The signal was also detected coherently by the new follow up detection system at 1/10th the above strength. This is necessary because the remote follow up antenna at MOPRA has substantially less sensitivity than the main antenna at Parkes.
By the way, Project Phoenix was featured in an excellent article in the October 17, 1994 issue of Forbes Magazine. This is the "400 Richest People in America" issue and may still be found on some newsstands. If you didn't get a copy and would like to receive a reprint, drop us a note.
Pierson is Executive Director of the SETI Institute.
The International Academy of Astronautics' 23rd Annual Review Meeting on SETI took place in Jerusalem in October, at the 1994 meeting of the International Astronautical Congress.
In the session on SETI Science and Technology, the Rudolph Pesek Lecture was given by Nikolai Kardashev of the Astro Space Center in Moscow. He spoke about the possible use of future space VLBI systems for SETI. Together with ground-based telescopes, the Millimetron program might someday be able to conduct very deep minisurveys to image suspected large scale astroengineering structures built by advanced civilizations. Ivan Almar, of Hungary's Konkoly Observatory, spoke about microwave space VLBI observatories and suggested the addition of a SERENDIP type of spectrum analyzer to the ground telescopes so that commensal SETI analyses could accompany the primary VLBI target observations. Roger Malina summarized the results obtained to date with the SERENDIP III system constructed at the University of California, Berkeley. In three years of observing at Arecibo, SERENDIP has detected over 400 candidate ETI signals. However, this is about the number expected from Poisson noise statistics. A much more powerful SERENDIP IV system is now being assembled. Raul Colomb, from the Instituto Argentino de Radioastronomia, described his three year southern hemisphere search, using a META system similar to that constructed by Horowitz at Harvard. He also found a large number of candidates, but again not more than would be expected on statistical grounds.
Ehud Pardo, of the SETI Institute, presented his design for the Fast Fourier Transform board of the new Follow Up Detection Device to be used by Project Phoenix in its upcoming microwave search from Parkes, Australia. Stuart Kingsley, of ETI Photonics, discussed his Optical SETI Observatory, which will come on line in 1995. He will examine the same 800 solar-type stars that Phoenix is studying, but will look for very short and powerful pulses in the visible and near-infrared. Finally, Tsevi Mazeh, of the Center for Astrophysics, described the results of a many years' study of radial velocity variations in nearby stars. The statistics are beginning to yield more convincing evidence for substellar companions.
The second Jerusalem SETI session, on "Interdisciplinary Aspects," will be summarized in the next issue of SETI News.
Billingham is Chairman, SETI Committee, of the International Academy of Astronautics.
Like the invention of television, discovery of the first extra-solar planets is a highly competitive endeavor, involving parallel efforts by many researchers. Nonetheless, when the trophies are given out, an obvious winner will be Alex Wolszczan, Professor of Astronomy at Penn State University.
Wolszczan studies millisecond pulsars, the squashed corpses of large, dead stars beaming light and radio pulses into space. The pulses are exceedingly regular, making the rapidly ticking millisecond pulsars among nature's best clocks. By counting the radio ticks over long periods, subtle slowdowns or speedups can be found. Indeed, for the pulsar B1257+12, monitored over a four year span, Wolszczan can detect arrhythmia's as small as one part in 1014.
And he has. B1257+12 exhibits cyclical heartbeat patterns extending over weeks. There is but one reasonable explanation for the irregularities: the pulsar is dancing ever-so-slightly around a center of mass it shares with encircling planets. The tiny wobbles, as small as mere millimeters per second, cause a Doppler shift in the pulse period, seen as a variation in pulse arrival times. Astronomers agree that it is the best evidence to date for extra-solar system planets.
According to Wolszczan, B1257+12 has at least three orbiting progeny, tipping the scales at 0.015, 3.4, and 2.8 Earth masses, and having orbital periods of 25.3, 66.5, and 98.2 days. The farthest is about half the distance from the pulsar as Earth is from the Sun.
Wolszczan continues to put in more time at the Arecibo telescope, hoping to find additional planets about this billion year-old corpse, and is scrutinizing other pulsars as well. While pulsars are a pathological host for orbiting worlds, the Penn State researcher believes that planets were first uncovered around these dead stars only because of the sensitivity of the technique. Should we remain sanguine about the possibility of plentiful planets elsewhere? Wolszczan says yes: "As long as there's no good reason to become pessimistic, I remain optimistic."
SETI News has learned that Andy Fraknoi has been named the 1994 recipient of the Annenberg Foundation Award of the American Astronomical Society (AAS). This prestigious honor recognizes an exceptional lifetime contribution to astronomy education. Previous winners have included Carl Sagan of Cornell, and Dorit Hoffleit of Yale.
Fraknoi will officially receive the award at the January, 1995 meeting of the AAS in Tucson, where he will give an invited lecture on the state of astronomy education in the U.S.
The award cites his work in the classroom, in promoting astronomy in the media, his debunking of pseudo-science, and his efforts in the field of teacher training. Fraknoi is currently head of the Astronomy Department at Foothill College, in Los Altos, California, and is well known as the former Executive Director of the Astronomical Society of the Pacific. He is also on the Board of Directors of the SETI Institute.
When asked how he felt about the award, Andy's understated reply was that it was "pretty exciting."
A group of SETI supporters will meet for a short discussion and dinner at the American Academy for the Advancement of Science (AAAS) meetings in Atlanta, February 17. If you would like to join us, please contact Lori Marino, Department of Biology, Rollins Research Center, Emory University, Atlanta, GA 30322 (tel: 404-727-2937; fax: 404-727-2880) or Donald Tarter, 591 Sharpes Hollow Road, New Market, AL 35761 (tel. and fax: 205-379-3580).
(Picture of Phoenix Team to be added here.)
A week before departing for the warm climes of Australia, the Project Phoenix receiving system (packaged in a truck trailer known as the Mobile Research Facility) serves as a background for some of the people who built it. About two dozen members of the development team donned their Phoenix shirts to pose in front of their handiwork. While hard to recognize in this reproduction, these are engineers, software experts, and managers that, with their brains and their hands, have fashioned a device that may finally put us in touch with our cosmic brethren.
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