[meteorite-list] Why We Fear Ourselves More than Asteroids
From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:02:32 2004 Message-ID: <200203261727.JAA11646_at_zagami.jpl.nasa.gov> http://www.space.com/scienceastronomy/solarsystem/asteroid_fears_020326-1.html Why We Fear Ourselves More than Asteroids By Robert Roy Britt space.com 26 March 2002 In the past six months, while the world focused on the continuing threat of global terrorism, as many as a dozen or more asteroids sneaked up on the Earth and zoomed by at distances just beyond the Moon's orbit and closer. Most were never noticed. Earlier this month, astronomers did spot one. Four days after it flew by. In discussing these events, experts describe a planet vulnerable to an unexpected attack that could, in an instant, wipe out a city or even destroy civilization. Some researchers go so far as to view the asteroid threat as an "international emergency situation," as Andy Smith of the Safety Research Institute in Albuquerque New Mexico said last week. Yet as billions upon billions of dollars are spent to provide insurance against terrorism, astronomers were foiled in a recent attempt to encourage Australia to invest a comparatively paltry $1 million to scan the mostly unsurveyed southern skies for killer space rocks. The scientists were practically laughed at on television by the science minister of Australia who, like much of the world's public, simply does not take the threat of asteroids seriously. The reason is simple: The Dread Factor is not high enough. Paul Slovic, author of "The Perception of Risk" (Earthscan, 2000), says most people are far more worried over what humans and technology can do to them than they are about natural disasters. While terrorism, chemical spills and nuclear accidents are awarded high "Dread Factor" marks by most people, asteroids, earthquakes and hurricanes rate low. Stealth approach On March 8, a hunk of stone and metal about the size of an 18-story building, made its closest approach to Earth, passing roughly 298,400 miles (480,200 kilometers) from the planet, just a bit farther out than the Moon, but a little too close for comfort for most astronomers. But what was most disturbing was that the asteroid, later named 2002 EM7, passed virtually unseen. Not until March 12, when it had moved out of the glare of the Sun and into the night sky was it seen from Earth. And it was not alone: On Jan. 7, an asteroid the size of three football fields came within two lunar distances and was spotted only a month before. Last October, a smaller asteroid passed by at a similar distance and was detected just two days prior. For each nearby asteroid that is spotted, several pass entirely unnoticed, some closer to us than the Moon, scientists say. One researcher estimates that each year, 25 asteroids roughly as large as 2002 EM7 whiz by at even closer distances. They slip through because of limitations to technology, telescope time, and funding. These close brushes illustrate a message that asteroid researchers have repeatedly tried to hammer home to politicians and the public: The number of undiscovered asteroids far exceeds the known list, and the list needs to be filled out before it's too late. Asteroid 2002 EM7 left a a pretty ominous message on its own: Only a tremendously expensive new telescopes -- placed outside Earth's orbit so as to monitor the blind spot created by the Sun -- could guarantee we won't suffer an unexpected and sudden impact. There would be a flash of brilliant light in the sky, and seconds later the world would change forever in a way that would render Sept. 11 an insignificant memory. Dread Factor vs. reality of risk Scientists develop asteroid risk statistics by estimating the total number of objects that exist and by studying evidence of past encounters -- big holes in the ground called impact craters. >From these clues, they say your chances of death by asteroid are about the same as dying in a plane crash, roughly 1-in-20,000 during your lifetime. You're more liable to be electrocuted to death (1-in-5000 chance), succumb to skin cancer or be killed in a car crash. Yet asteroids pose more risk than tornadoes (1-in-60,000 chance), rattlesnake bites or food poisoning. If Earth is hit, you could die by direct impact and vaporization. Or you might be killed in an associated earthquake or volcanic eruption as the planet's bell is rung like never before in recorded history. Or perhaps like countless lesser species, you'll die a slow, agonizing death of starvation as the world's food supply dwindles in the face of reduced sunlight caused by a global debris cloud. Yet if you're like most people, you are not all that worried, according to sociologists and psychiatrists who study these things. Slovic, the author, also works at Decision Research, an organization in Oregon that advises industry and government about risk. He says we do not base our fears on statistics. Instead, each of us develops our own personal Dread Factor for various frightening scenarios based on personal experience, knowledge and, more important, our sense of the situation. Emotion has replaced instinct as a major risk-assessment tool for modern humans, who face myriad dangers, none of which involve sneaking up on woolly mammoths from behind a tree. "It is more of a gut feeling," Slovic says. "Does it worry me? Does it scare me? Does it make me uneasy?" Cars are low on most individuals' Dread Factor lists, even though the average American stands about a 1-in-100 or 1-in-200 chance of dying in an automobile. "We don't dread cars," Slovic says. "Things that cause cancer are high on the Dread Factor." Scientists vs. voters The Dread Factor, or lack of it, can drive political funding decisions. The U.S. Congress apparently perceived the threat real enough to require NASA to make asteroid hunting a serious business. The space agency spends $3.55 million each year searching for and studying asteroids. (Much of that money goes to space-based research of asteroids that pose no threat.) Individual search programs provide much of their own institutional funding. And amateur astronomers around the globe contribute to the effort. Not everyone, however, sees an urgent need. The Australian Science Minister Peter McGauran, appearing on his country's 60 Minutes television program March 17, called the effort to find potentially threatening asteroids "fruitless, unnecessary, self-indulgent" and promised no funds unless researchers provide a more convincing argument for the need. To the consternation of many researchers, there are no telescopes below the equator devoted to searching southern skies for asteroids. Australia cut funding to one such effort in 1996. An ongoing online poll taken in conjunction with the televised program found overwhelming support -- 91 percent at last count -- for reinstatement of the funding. But these votes were cast by people who watched an animated asteroid slam into Earth and listened to leading experts spout frightening statistics and detail the grim outcomes they say are only a matter of time. You and most other voters, in Australia and around the world, probably lean more toward McGauran's sentiment. According to experts in risk assessment and fear management, McGauran's starkest statement likely reflects the general public mood: "I lie awake worrying about a lot of other things. Near-miss asteroids is not one of them." The average person tends to be much more afraid of industrial accidents, for example. As with terrorism, vast sums of money are spent, as Slovic puts it, "to take small risks of chemical and radioactive pollution and reduce them even further. We spend a huge amount for every statistical life saved. On the other hand, if you wanted to get people to spend money on asteroid protection or earthquake mitigation, it's very difficult, even though the risk is much greater." Richard Taylor of the Probability Research Group, a global affiliation of researchers looking into various science topics, thinks there is a clear message in the fact that nations spend billions on military defense but zero scanning our entire Southern Hemisphere flank for asteroids: "We feel more at danger from man than from Nature," Taylor says. Not in my lifetime A decade ago, Slovic and some colleagues conducted a test. They provided a group of university students with information about the threat from beyond, explaining that a giant asteroid was thought to have killed off the dinosaurs, and others would surely hit the planet at statistically determined intervals. Then they surveyed the students to determine how they assessed the risk. The students recognized the threat, but chose not to worry about it. "They're expectation was, well, it's not going to happen in my lifetime," Slovic says. If astronomers were to announce an imminent collision, asteroids would suddenly develop a high Dread Factor, Slovic figures. But because none of us has any direct experience whatsoever with deadly space rocks, "People don't get worked up about it. There's too many things to worry about." Scientists find it similarly difficult to generate much public worry for other potential calamities, like horrible storms, droughts and coastal flooding that might result over the next century due to climate change, but which are seen as remote in time. There is little chance that the complacent attitude of the public, and of some government officials, will ever elevate to the level of concern maintained by asteroid experts. As Slovic says, it's common for scientists and technicians to have a different and more rational understanding of the risks involved in their area of study. Fear as a motivator Many astronomers, it must be noted, believe present asteroid search efforts are fairly adequate, notwithstanding the lack of a southern telescope. With time, they say, the worst threats will be rooted out, which is to say the largest asteroids. And, they argue, the odds are that if any globally destructive object is found to be on a collision course with Earth, there will probably be years of warning. A more vocal group of astronomers and other proponents of increased spending tend to worry about smaller asteroids that could cause regional devastation. And they tend to make more frightening statements. Here are just a few that have come from the mouths of respected experts just in the past 10 days: "If it were over a populated area, like Atlanta, it would have basically flattened it," asteroid cataloguer Gareth Williams told CNN in discussing the potential of asteroid 2002 EM7. "We live in a cosmic shooting gallery," said Duncan Steel of Salford University. "We're talking about a million megaton explosion," said author and physicist Paul Davies of Macquarie University, in discussing a typical impact on another recent television program. "That's a million city-bursting bombs all going off at once." While such statements are often softened with the reminder that the world probably won't end tonight -- Davies said in the next breath, "I don't want people to lie awake at night worrying about it" -- the effort is clear: Get you and the politicians to act on this threat. Yet in a world remade by a single day of terrorism, fear may be doomed as a sales pitch, just as it was in Australia. Fear is not something that can necessarily be instilled by scientists. Instead, it tends to be generated by whatever rears its ugly head and shouts loudest, explains Robert Butterworth, a psychologist at International Trauma Associates in Los Angeles. Nothing right now, globally speaking, can measure up to the fear of terrorism and the associated potential of a nuclear attack. I can't take it While there are plenty of things for a 21st Century human to worry about, we all have our limits. "In order for us not to have these things on our minds, we use a device that's been maligned in last few years, which is denial and repression," Butterworth says. "We push it back, because we couldn't function if we didn't." Asteroids, like a fear of bugs or concern over a missed appointment, can be lost in a shuffle of frightening thoughts. Some things just aren't as significant as they seemed last summer. Butterworth puts it this way: "If we had been walking with a limp and all of a sudden were shot in the stomach, the limp fades away." No place has been hit in the stomach like New York City. Psychologist Janice Yamins, whose patients include victims of the terrorist attacks, says residents are stunned by their own change in views, such as newfound support for defense spending "instead of other things that won't help preserve our world." Where fear leaves off, anger and revenge step in. Natural disasters don't generate similar sea changes in philosophy. Californians suffer tremendously from earthquakes every few years. They pick up and move on. Southeast coastal residents rebuild time and again after hurricanes. People there shrug off the threat. Butterworth figures an asteroid impact would generate similar reactions. "What do we do, shake our fist at God?" he asks. "Who can we be angry at?" All this psychology lends support to a notion that has already formed in the heads of many astronomers: Their call for more funding will fall on a whole lot of deaf ears until another asteroid makes real noise. The last serious impact was in 1908, when a rock about the same size as 2002 EM7 exploded above the surface of Siberia. Roughly 1,200 square miles (3,108 square kilometers) of forest were flattened in a remote region known as Tunguska. There were no known deaths, because almost no one lived there. The odds of a similar event, which could easily destroy a large city or a small state with miles of extra destruction to boot, are about 1-in-20 over the next 50 years. Knowledge and false alarms In the past decade, about 500 very large space rocks have been found to wander near the space shared by Earth's orbit. These so-called Near Earth Asteroids, all larger than 1 kilometer (0.6 miles), represent about half the expected total. Millions of smaller asteroids are almost entirely uncatalogued. The larger rocks are the ones many scientists fear most. If one hit Earth, civilization would be pushed to the brink and perhaps beyond. Deaths could easily be counted in millions, possibly even billions. Many species of plants and animals would disappear. As more asteroids are discovered and publicized, public awareness of the threat grows. But the information is not always accurate. In a couple of high-profile cases, most prominently four years ago with an asteroid called 1997 XF11, the public was warned of potentially devastating impacts before further calculations showed the newly found rocks to be no threat at all. Worse, late-night radio programs and various web sites spout all sorts of unscientific claims of impending asteroid doom, reports that spread like tsunami radiating outward from an ocean impact. Any reporter who covers the subject has gotten more than a few frantic e-mails from concerned citizens who heard this or that and were worried about the planet-destroyer coming next June, or whenever. Movies like Armageddon only enhance "wild inaccuracies" in some minds, says Taylor of the Probability Research Group. All of this -- the fact, the fiction, the unfounded fears and the genuine threats that some people don't fear at all -- create a gulf of apathy and misunderstanding that may well prevent asteroid experts from convincing you to see the world as they see it. Several dozen professional astronomers, meanwhile, maintain a nightly vigil in the Northern Hemisphere, scanning immense and dark skies for tiny points of light, then struggling to observe often minor movements against the background of stars in order to determine a trajectory, an ultimate destination. Always on their minds: Will this one hit Earth? "It isn't a matter of if one of these things is going to hit the Earth," said Duncan Steel on the 60 Minutes broadcast. "It's just a matter of when. Either we can expect 23 years warning or six or seven seconds." For those in the know, the asteroid Dread Factor is off the charts. Received on Tue 26 Mar 2002 12:27:07 PM PST |
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