The Big Ear
By Kym Kuenning
February 11, 1998
Exobiology: Science without a Subject
"Our age is not one to look for God in the cosmos," wrote Time's Charles Krauthammer... "We are looking for life, for contact, for a reflection of ourselves."
An unidentifiable light glimmered above a suburban home in Madison, Wisconsin in the early fifties. Motionless and silent, the silver disc flickered long enough for a young boy to retrieve his telescope.
Bob gazed through the small eyepiece for just a second and realized a great truth about scientific inquiry and about the scientists who inhabit our small corner of the Universe.
Director of one of the world's first and longest-running radio telescope programs, Ohio State University's (OSU) Dr. Robert S. Dixon is still gazing. His boyhood telescope matured into a marvelous feat of electronic engineering: an expensive radio telescope complete with an underground computer analysis system. The telescope scans the sky on a frequency designated only for astronomical objects and listens for a specific type of radio signal which might imply the existence of an intelligent civilization. But as of December, 1997, the twenty-three year old program, signed out. Country-club developers purchased the property and they were sitting on the eighteenth tee.
A Mainstream Science
It is far too mundane for my taste to write a story about the profound influence of capitalism on scientific inquiry. This is a story about human perception of the unknown and about the determinism of a handful of enthusiasts who won't take no for answer. You don't need to know what a wavelength or a frequency is to follow this story. Neither did I when I wrote it (and I still don't).
According to Dr. Dixon, anything from pure hydrogen to blades of grass to humans emit natural radio signals. Having said that, it stands to reason that the Earth is constantly bombarded with radio signals from billions of stars and their planets surrounding them.
Ohio State's radio telescope, Big Ear, collects these natural signals from outer space and sends them to underground computers for interpretation. Russ Childers, Chief Observer at Big Ear conducted a five-year, all-sky survey to record changes in the level of intensity of natural celestial radio sources since the original survey completed 25 years ago. The purpose of the survey was also to look for unnatural radio signals, implying creation from an intelligent source.
Childers said, "I moved the telescope twice a week so it would carve out overlapping stripes of the sky. The Eath's rotation causes stars to pass through the beams of the telescope. If an interesting signal is seen, the receivers move, canceling out the effects of the Earth's rotation, allowing the source to be observed for up to two hours."
Astronomers agree that an unnatural radio signal created by an intelligent civilization would appear as an artificial design. The most obvious indicator would be a coded signal containing a basic unit of information (a bit) such as a binary-number system (two characters) enabling the observer to create a recognizable image of universal significance - a sphere, a figure representing the value of pi or maybe even a stick figure of a body. Several thousand candidate signals have been logged for possible extraterrestrial origin.
The OSU program earned overnight fame. On August 15, 1977, Jerry Ehman glanced over his computer printouts and found a very unusual pattern riding in on a frequency not used by aircraft, satellites or terrestrial objects. Thirty times louder than the background noise, this signal came in through one of fifty channels and was not moving with the Earth, but with the stars. The signal wasn't caught on the telescope's second sweep. It had turned itself off. (Today's technology allows questionable signals to be tracked and electronically recorded.)
Since the signal was never again heard, some researchers concluded it may have been a stray earthly beam bouncing off an incoming meteor. Others suggest it was a military satellite using an illegal frequency. Even Dr. Ehman wouldn't spin a good yarn for me. "It will probably forever be an open question ... it's the best example of a possible signal," he said.
The instrument, utilizing a sensitive 21-centimeter receiver, looks like an erector-set football field with a data-collecting area at each end. The standing parabola is 320 feet long by 70 feet high. The ground plane, the area between receivers, is about three acres and covered with "heavy-duty aluminum foil" to reduce local microwave signals.
Robert Dixon's emotional fervor uniting theory with practice earned him a place at the helm at the Big Ear Observatory. As a graduate student in the sixties, he worked with radio astronomer, John Kraus, to draw maps and categorize some 20,000 natural outer-space radio sources with a telescope Kraus built and christened Big Ear. When funding for the mapping project was exhausted, Big Ear lay idle. It was Dixon who suggested they use it to search for extant signals. The team's enthusiasm for the project lured engineering students willing to keep vigilance at odd hours and eager to design new receiver components for course credit.
Along with the provision of a map of natural radio-sources in the sky, Big Ear provided the discovery of cold hydrogen clouds in outer space and valuable information regarding the composition of the universe. Radio astronomers can also take credit for advancements affecting our everyday lives in microwave communication, digital-signal processing and computer software. Never again has anything quite as unusual as Dr. Ehman's signal crossed their airways.
One Moment in Time
Not all scientists need golf-course size laboratories. Some researchers, called exobiologists, turn their scopes toward bacteria on Earth in their search for life outside our planet.
University of Cincinnati Associate Professor Brian Kinkle explained, "Potential life on other planets will be restricted to sites with liquid water." To date, there has not been a discovery of surface water anywhere in or outside our solar system. However, recent NASA findings suggest the presence of subsurface water on a moon of Jupiter and on the planet Mars.
Dr. Kinkle said that, previously, biologists believed that all ecosystems were based on energy derived from sunlight, hence organisms cannot live too far from the Earth's surface. But in the late 1970s, unusual communities of bacteria and animals were discovered in deep-sea hydrothermal vents located on the ocean floor. These deep-sea ecosystems appear to use a process for energy consumption which is not dependent on sunlight, called chemoautotrophy. Recently, scientists discovered an ecosystem in a Romanian cave that also appears to be based on this process.
If bacteria on Earth can exist in deep-sea vents without sunlight, so it can on other worlds.
Alright, so these little bugs don't exactly have the emotional zip and excitement of little green men. It is a step in the right celestial direction. Consider now that current understanding of evolution concludes that only life structures that are capable of undergoing change throughout the millennium will survive an alteration in the global environment. Any living cells found on another world might represent just one moment in the evolutionary process of a planet; a moment that when followed by similar environmental changes as the Earth might lead to intelligence and conscience.
"Evidence suggests that microorganisms from deep within the Romania system may represent early forms of life on Earth or possibly on other planets." concluded Dr. Kinkle.
He and his team are studying the Romanian bacteria in more detail. Their work was funded by the National Science Foundation and featured in an article in Science Magazine. The U.C. team is pursuing funding opportunities with NASA.
Within NASA today, exobiology is conducted by the Life Sciences Division. Its overall goal is to understand the origin, evolution and distribution of life in the Universe through ground-based and space-based locations. Research shows that water is believed to be widespread throughout the universe.
Testing the theory that life is a natural consequence of the physical and chemical processes created by the overall evolution of the cosmos requires a rigorous research program. Studies of Halley's Comet revealed the presence of a variety of simple organic compounds (essential for life) and the familiar elements of carbon, hydrogen, nitrogen and oxygen. These elements have also been observed in clouds in outer space. Perhaps the discovery that created the biggest media frenzy at NASA was the discovery of life-implying compounds on a Martian rock found at the South Pole.
Terrence Toepker, Nuclear Physicist at Xavier University said, "It seems improbable that the Earth would be the only planet that would have developed life. We just can't prove it."
Dr. Dixon, who also serves as Senior Research Engineer at Ohio State, agreed, "It would be stranger if we never found life. The same laws of physics, the same chemicals, temperatures and pressure exist everywhere in the universe. There's no reason to believe that life evolved only on the Earth."
What Separates ithe Charlatans
Dixon's team can take a hint when they're not wanted. The developers removed paved access to their facility. Water damaged some equipment and went uncompensated. The university and the government pulled their funding. Big Ear's ground plane overgrew with weeds. Beam by beam, Big Ear was dismantled; its spare parts divided according to its reuse value.
As we spoke before the closure, bulldozers pounded the grounds around us carving out the remaining nine holes of the adjacent golf course. Nonetheless, the radio telescope continued to survey the sky one section at a time until by law it had to cease. Downtrodden, busted flat, but not beaten.
Pardon the dust, the dream lives. The team of volunteers is staffed by an enthusiastic lawyer, several scientists, a few die-hard graduate students and one optimistic fund raiser. They have plans to move their office to a crackerjack box on Ohio State's campus and move forward with their scant blueprints and budget to build a better alien trap. Their work is being executed by a volunteer organization called the North American Astrophysical Observatory (NAAPO) carrying a new technology designed to be of comparable sensitivity and resolution, but about 500,000 times more efficient than Big Ear. This system will observe the entire sky above the horizon rather than one small section at a time, like most dish-type antennas.
"There's never a dull moment. There's always the technical challenge to build a better receiver or to write a better computer program. Our work contributes to a cause, even if we, ourselves, never find anything," said Dr. Dixon.
That's what young Bob learned about scientific inquiry and what it is that separates the charlatans from the scientists. On that clear, summer day in Madison, Wisconsin, when Bob peered through his small telesco at an unidentified flying object, he saw a shiny weather balloon, its gondola clearly suspended with cables.
He said, "It was a perfect example of scientific method. I first postulated this was a flying saucer, but my original explanation was inconsistent with the new data. I learned an important lesson about scientific inquiry. We can be wrong about what we think we see, no matter how diligent or careful we are."
Another volunteer said, "If after a generation or so of exhaustive monitoring, we fail to find verifiable signals of extraterrestrial origin, we may be forced to reluctantly concede that we are, indeed, alone in the universe. Isn't that discovery, too, worth the price of admission?"