Faint Echoes, Distant Stars_The Science and Politics of Finding Life Beyond Earth

by Ben Bova

  BETWEEN TARZAN AND THE ANGELS

  While there may be many, many civilizations among the stars, some of them may be so much older (or younger) than we are that communicating with them would be impossible.

  What are the chances of finding an intelligent civilization at our level of development?

  Consider the history of the Earth. Let our planet’s 4.5 billion years be represented by the height of the Empire State Building. At that scale, the human race’s few million years of existence can be represented by a 1-foot ruler standing upright at the top of the building. The thickness of a dime placed atop the ruler represents the entire span of our civilization—some 10,000 years. On top of that dime, glue a postage stamp. Its thickness is equivalent to the length of time since humankind has developed modern science: nearly 400 years.

  The Milky Way may be brimming with intelligent species, but how many of them are in the same phase of development—and technology—as we are? How many are within the thickness of that postage stamp? They are the ones we will be most likely to communicate with.

  Older, more developed species might not deign to talk to us. They might regard us as no better than apes or insects. Perhaps they will want to study us, as human anthropologists study the primate apes. But to make such studies valid, they would have to avoid letting us know they are watching us.

  On the other hand, younger species will not yet have invented technologies capable of interstellar communication.

  To make contact with an extraterrestrial civilization, we will have to locate one that is close to our own level of development, somewhere between Tarzan and the angels.

  OPTICAL SETI

  If alien civilizations are so far ahead of us technologically, they might well be talking back and forth across the stars with devices we can’t even dream of. Is there anything we can think of that would serve as an interstellar communications technology?

  What about lasers? We use miniature lasers in our telephone systems, where their beams of light carry information through fiber-optic cables. Might aliens be using powerful laser beams to chat over interstellar distances? And if they do, might some of those laser beams be occasionally pointed our way, so that we could detect them? Lasers emit very intense, narrow beams of light. Even a low-power laser beam is actually brighter than the Sun. Although clouds of interstellar gas and dust may absorb some laser beams, the kind of high-power lasers that an advanced civilization could build should be able to penetrate through the galaxy and even beyond.

  This is the reasoning behind Optical SETI, the idea that we should be looking for intense beams of laser light among the stars, in addition to searching for radio signals.

  The father of Optical SETI is Dr. Stuart A. Kingsley, who began searching for optical extraterrestrial signals in 1990 using a 25.4-centimeter telescope in an observatory he built in the backyard of his home in suburban Columbus, Ohio.

  The English-born Kingsley, an optical engineer by profession, calls his homebuilt facility the Columbus Optical SETI (COSETI) Observatory. For the past decade he has not only spent his nights searching the heavens, he has also organized scientific conferences on Optical SETI, written papers on the subject, and launched an Internet Website, www.coseti.org.

  Kingsley flat-out believes radio is the wrong medium for interstellar communication, in part because the thin hydrogen gas that pervades interstellar space tends to smear radio signals beyond recognition. “Interstellar dispersion and scintillation effects badly corrupt radio frequency communications,” he asserts. “Only lasers have the ability to probe across interstellar space, free of significant distortion, and thus become capable of supporting wide-band communications.”

  Searching for laser light, especially the very brief pulses that would most likely be used for communication, gets around one of the biggest problems that has bedeviled radio SETI: guessing which of the billions of available radio frequencies the ETs might be using. Optical SETI simply looks for optical or infrared pulses with detectors that—like the human eye—can pick up a broad spectrum of frequencies.

  While laser beams may be absorbed by interstellar clouds, they have the advantage of being bright enough to be easily noticed by optical detectors, especially if the laser is pulsed. Here on Earth, laser pulses in the nanosecond range (a billionth of a second) have reached power peaks of trillions of watts—plenty of power to cross interstellar distances.

  Existing lasers are capable of very short pulses in the 1015-watt range (a petawatt, or a billion megawatts). Such laser pulses are 5,000 times brighter than the Sun. And distance does not matter: Both the star’s brightness and the brightness of the laser diminish at the same rate. A laser pulse that is 5,000 times brighter than the Sun will still be 5,000 times brighter than the Sun no matter how far away an observer may be. Thus, it should be easy to distinguish a deliberate laser pulse from the star near which it originates.

  Thanks to Kingsley’s untiring efforts and a growing disenchantment with unsuccessful radio searches, the move toward Optical SETI is gaining momentum.

  ONGOING OPTICAL PROGRAMS

  Dan Werthimer and his colleagues at the University of California, Berkeley, are searching for alien laser flashes using the 76.2-centimeter telescope at Leuschner Observatory in the hills east of San Francisco Bay. Their team includes Charles Townes, who did the earliest theoretical work on lasers while at Bell Labs in the 1950s.

  Paul Horowitz, father of the META and BETA systems, who since 1986 has led a team using the Harvard radio telescope dedicated to SETI, has also branched into Optical SETI. Working in cooperation with optical astronomers, Horowitz is “piggybacking” photon detectors on telescopes being used for other observations and examining the results for evidence of laser pulses. So far, he reports, the equipment has detected cosmic ray flashes but no intelligent laser signals.

  Both the Berkeley and Harvard Optical SETI work are supported by the privately funded SETI Institute and the Planetary Society.

  The SETI Institute is also collaborating with the universities of California at Santa Cruz and Berkeley on using the 1-meter Nickel Telescope at Lick Observatory to search for laser beacons. With three optical detectors working simultaneously, SETI Institute chairman Frank Drake believes they can eliminate false alarms.

  Horowitz sums up the prospects for Optical SETI in words that ring with overtones of Cocconi and Morrison: “No one knows for sure whether optical communication will turn out to be the method of choice for advanced civilizations seeking to establish contact. But a directed laser beacon is altogether reasonable, from all we know.”

  Intelligent aliens may be out there, and we simply have not yet detected their very small needle in that very large haystack of the Milky Way galaxy. Or they may not exist at all. We have no way of knowing, so the search continues.

  Or they might be observing us without our knowing it, unobtrusively studying us the way modern primate researchers try to blend in with troops of chimpanzees or gorillas.

  There are those who believe that this is precisely what is going on.

  19

  UFOs, Abductions, andAncient Astronauts

  Where is everybody?

  —Enrico Fermi

  Don’t bother, they’re here.

  —Stephen Sondheim

  Send in the Clowns

  WHILE ASTROBIOLOGISTS and SETI researchers strive to determine if life and intelligence exist elsewhere in the universe, a persistent group of people (including some scientists) earnestly believe that our planet has already been visited by intelligent extraterrestrials and is still being visited by them today. Their claims are so widespread and so insistent that serious scientific investigations have been devoted to assessing the reality of their reports.

  The problem bedeviling such investigations lies in determining the reliability of the available evidence. Scientists want solid physical evidence and phenomena that can be repeated and studied carefully. Reports of unidentified flying objects and alien visitations have been, at
best, fragmentary and anecdotal.

  UNIDENTIFIED FLYING OBJECTS

  On the shelf by the window of my office rests a long-empty bottle of Cigare Volante, a delightful dry red wine from the Bonny Doon Vinyard of Santa Cruz, California.

  In addition to being an excellent wine of the Côte-du-Rhône type, Cigare Volante is a reminder that UFOs are not a recent phenomenon. Around the turn of the twentieth century, numerous sightings of strange, cigar-shaped objects in the sky were reported in several regions of Europe. The fact that Count von Zeppelin was testing large, rigid airships that eventually became known as dirigibles (the most famous of which, nearly forty years later, was the ill-starred Hindenberg) might have had something to do with the sightings.

  People have seen strange objects in the sky since biblical times, at least. Once attributed to angels or other supernatural causes, in the mid-twentieth century, the general public was familiar enough with the idea of extraterrestrial life that UFOs—unidentified flying objects—came to be ascribed to alien visitors from other worlds.

  The modern interest in UFOs began June 24, 1947, when private pilot Kenneth Arnold, a Washington state businessman and a deputy U.S. marshal, was flying his plane near Mt. Rainier. He reported seeing nine disk-shaped objects flying in formation at a speed of more than 1,000 miles per hour, far faster than even the new jet fighters of the day could fly. The objects appeared to be pitching up and down, “like a saucer if you skipped it across the water,” Arnold said.

  The term flying saucer was immediately trumpeted across the world by the news media. Before the year’s end, nearly 1,000 more flying saucer sightings were reported.

  In 1947, World War II was still a very fresh memory. The war had ended with nuclear bombs devastating Hiroshima and Nagasaki and V-2 rockets raining destruction on London. The public leaped to the conclusion that flying saucers were visitors from outer space.

  The public had a considerable amount of help in coming to that conclusion. A minor industry sprang up among magazine and book publishers, hammering at the idea that “we are not alone.” Soon Hollywood got on the bandwagon with a succession of lurid and mostly ludicrous exploitation films that substituted alien monsters for the older-style vampires and werewolves. A few of the films were earnest attempts to portray realistically the possibilities of alien contact. The Thing from Another World (RKO Radio Pictures, 1951) and The Day the Earth Stood Still (20th Century Fox, 1951) were both developed from insightful science fiction stories that had been published more than ten years before.

  The U.S. Air Force became interested in UFOs, perforce. In the nervous Cold War environment of the time, the Air Force had the responsibility of protecting the nation against attack. Far from worrying about alien invaders from outer space, the Air Force wanted to know if some other nation (Soviet Russia, for example) had developed aircraft that could outperform anything in the American armory. In 1948, the Air Force initiated Project Grudge, a formal investigation of UFO reports.

  As part of Project Grudge, the Air Force employed astronomer J. Allen Hyneck (1910–1986) of Ohio State University to examine possible astronomical explanations for UFO sightings. Hyneck, who later became associate director of the Smithsonian Astrophysical Observatory, was originally skeptical of the UFO reports. Gradually he moved to a more open-minded position and insisted that the sightings should be taken seriously and investigated by scientists.

  Most scientists scoffed at the UFO sightings. Many “flying saucers” were shown to be meteors or a bright star; others were ascribed to ordinary aircraft, luminous swamp gas, or even mass hysteria. Some were proven to be outright hoaxes. Astronomer Donald Menzel (1901–1976), then director of the Harvard Observatory, who had written science fiction under various pen names, found “with a slight feeling of disappointment” that even radar blips attributed to UFOs could be explained as entirely natural phenomena.

  Project Grudge officially ended in 1949 with a report written largely by Hyneck that attributed the vast majority of sightings to natural causes. There was a “residue,” however, of about one-third of the sightings that could not be explained in any way. Most scientists—and the Air Force—concluded that these were sightings where there simply was not enough information available to make a reasonable analysis. The UFO-logists, however, claimed that the “residue” were extraterrestrial visitors and the government was covering up their presence.

  The UFO sightings would not stop. And the publicity drums kept beating. Donald Keyhoe (1897–1988), a retired military officer and pilot who had been a public relations official at the U.S. Department of Commerce, began to write articles and books in which he firmly proclaimed that UFOs were spacecraft of extraterrestrial visitors.

  Private groups such as the Aerial Phenomena Research Organization (APRO) and the National Investigations Committee on Aerial Phenomena (NICAP) sprang up, all dedicated to examining the UFO phenomenon and leaning decidedly toward an acceptance of the extraterrestrial explanation. The largest such organization is the Mutual UFO Network (MUFON), which holds a well-attended conference annually.

  Faced with mounting public agitation over UFOs, in 1952, the Air Force started Project Blue Book, another organized examination of UFO reports. Sighting reports were carefully investigated; most of them evaporated into hearsay. Again, most of them were attributable to natural phenomena. And again, there were a few that could not be accounted for. Despite this small residue of unexplained sightings, the officer in charge of the program told the news media that while the Air Force could not deny the possibility that aliens were visiting the Earth, the UFO reports “offer absolutely no authentic evidence that interplanetary spacecraft do exist.”

  In 1966, the House of Representatives’ Armed Services Committee held public hearings on UFOs. Air Force Secretary Harold Brown, Blue Book director Hector Quintanilla Jr., and Hyneck all testified. Of the 10,147 sightings reported between 1947 and 1965, they stated, 9,501 were identified as natural phenomena. Of the remaining 646, Secretary Brown said there was no evidence that they came from beyond the Earth.

  After the House hearings, Hyneck suggested that the government appoint a panel of physical and social scientists to examine the Blue Book findings. The House committee recommended much the same course of action. Edward Condon (1902–1974), a professor and fellow of the Joint Institute for Astrophysics at the University of Colorado, was picked to head the study.

  For the next two years Condon and the other members of his committee laboriously sifted through the Blue Book material. Their work was marked by controversy, dissension among the committee members, and intense public interest—at least, among UFO-logists and other “believers.”

  The 967-page final report of the Condon committee concluded that, “nothing has come from the study of UFOs in the past twenty-one years that has added to scientific knowledge. Careful consideration of the record as it is available to us leads us to conclude that further extensive study of UFOs probably cannot be justified in the expectation that science will be advanced thereby.”

  Cover-up! screamed the UFO believers, cheerfully abetted by the small army of media personnel who were making their livings off the UFO phenomenon. This became a constant theme in UFO affairs: When a government agency said its investigation showed nothing, the “faithful” immediately claimed that the government was hiding the truth. This paranoid suspicion of conspiracy in high places is still evident in popular television shows such as The X-Files.

  And they were right, in at least one case. There was a government cover-up in the most famous UFO report of them all: the crashed “flying saucer” and alien crew members that were found at Roswell, New Mexico, in 1947. The cover-up lasted nearly fifty years, but when it was at last revealed most UFO-logists were bitterly disappointed.

  THE ROSWELL COVER-UP

  The most famous UFO incident happened in July 1947, just outside the town of Roswell, New Mexico. After a severe thunderstorm the night before, rancher William W. “Mack” Brazel found in the d
esert wreckage of a crashed aircraft of a type none of the local residents could identify. Even military officers from nearby Roswell Army Air Field seemed stumped. Soldiers collected the wreckage and within a day or two it was flown to Wright Field in Dayton, Ohio, a major facility that included several government laboratories.

  A few days after the wreckage was picked up by the Army, public relations officer Lt. Walter G. Haut issued a news release that referred to the wreckage as “a disk.” Over the following days, the story grew: The “disk” was definitely a flying saucer. Three alien crewmen had been recovered, two of them dead and the third badly injured. They had all been bundled off by the Army in great secrecy.

  In the 1990s, a television film, Alien Autopsy, purported to show the autopsy of one of the Roswell aliens. Even though one of the producers involved with the show later denounced the film as a hoax, it was taken by the UFO faithful as evidence for the authenticity of the Roswell crash.

  Back in 1947, shortly after Haut’s report of finding a “disk,” the Army quickly issued another news release claiming that the wreckage was nothing more than a weather balloon. Cover-up! again charged the UFO faithful, and for nearly half a century Roswell has stood as the classic example of the government hiding “the truth” about flying saucers. Hardly anyone bothered to ask why Washington would hide the news that intelligent aliens had visited Earth. My own feeling was that a government that could not hide petty shenanigans such as the Watergate burglary could hardly keep the news of extraterrestrial visitors a secret for decade after decade.

  Then, in 1994, the government finally admitted that there had indeed been a conspiracy to hide the truth about the Roswell wreckage. It wasn’t a weather balloon. But it wasn’t an alien spacecraft, either.