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February 8, 2005
Planet-Forming Process May Be Playing Out in Miniature
By DENNIS OVERBYE
Astronomers have found what they say may be a miniature solar system in the making.
In the latest example of the apparent fecundity of nature, a tiny starlike object too small to be a star seems to be surrounded by a tiny disk of dust that could someday form planets, which could perhaps even be briefly capable of supporting life, according to observations.
The discovery raises the possibility that astronomers will soon discover actual planets and habitable abodes around objects that are barely larger than planets themselves. The starlike body, only about 15 times as massive as the planet Jupiter, is the smallest object yet to be found with such a disk. With a temperature of 3,600 degrees Fahrenheit, it is also the coolest. As such, the object is not really a star at all, but a failed star known as a brown dwarf that is only barely bigger than the largest giant planets.
"It's just incredible," said Dr. Kevin Luhman of the Harvard-Smithsonian Center for Astrophysics. "A little disk that could form planets around an object that is small enough itself to be a planet." Dr. Luhman led an international team of astronomers that observed the brown dwarf, known as OTS 44, using the Spitzer Space Telescope. He will be discussing his results this week at a meeting on extraterrestrial planets at the Aspen Center for Physics in Colorado.A paper describing the results will be published in The Astrophysical Journal Letters.
Dr. Geoffrey W. Marcy of the University of California, Berkeley, said the report opened a new possible abode for life, on Earth-like planets orbiting brown dwarfs. "While these earths would be warmed up for only a few million years," he said in an e-mail message, "it is interesting to imagine what biochemistry might flicker valiantly during that brief period when the brown dwarf is luminous enough to warm up the earth, only to freeze over before Darwinian evolution can kick in."
The work continues a recent trend in which astronomers using bigger and bigger telescopes have shifted their attention somewhat, from the biggest and brightest objects in the cosmos - supernova explosions, quasars and giant galaxies - to the smallest and dimmest. Little dim things far outnumber their more striking and violent cousins, and it is among these humbler denizens of the cosmos that astronomers must look for life or life-friendly conditions.
The Spitzer Space Telescope, launched into orbit around the Sun in 2003, is the fourth and last of NASA's so-called Great Observatories. It is designed to see the infrared, or heat radiation emitted by celestial objects.
Cool dim objects like small stars, brown dwarfs and planets emit electromagnetic radiation most strongly in infrared wavelengths, which are longer than those of visible light, and which can pass through interstellar dust clouds that often shroud new stars, but Earth's atmosphere blocks infrared light. And so prospective infrared astronomers have had to go to space, starting with the Infrared Astronomical Satellite, IRAS, in 1983, which discovered disks of dust around several stars, including Vega.
Since then disks have been detected or have been inferred to exist around thousands of stars, including a few brown dwarfs. In December astronomers using Spitzer announced that they had detected the signatures of dusty disks around half a dozen stars already known to harbor giant planets, thereby closing the loop between disks and planets.
By searching out the smallest dwarfs that have such disks, Dr. Luhman and his team hoped to learn more about how brown dwarfs formed and determine whether planets could exist around such objects.
The brown dwarf, OTS 44, is part of a cluster of very young stars about 500 light-years away in the constellation Chamaeleon. When the astronomers looked at it with the Spitzer, they found that the brown dwarf was putting out excess heat at certain wavelengths, a signature of cooler material surrounding the brown dwarf.
The extra heat, they calculated, was coming from a disk of dust and perhaps larger materials, extending 300,000 to 900 million miles from the dwarf star, about a tenth the size of the disk that formed our own solar system. They estimated that there was enough material in the little disk to make a planet like Jupiter or several smaller Earth-like planets.
The disk around the brown dwarf is unlikely to have any planets, Dr. Luhman said; based on the ages of the stars in the cluster, the brown dwarf and its disk are only about a million years old. It could take 10 million years for the small bits and chunks of rock and dust to coagulate into planets.
But he added, "There could be little embryos we can't see."
A planet that orbited close enough to the brown dwarf could even be briefly habitable, meaning that liquid water could exist on it, Dr. Luhman said. This "habitable zone," as astronomers call it, would extend from one million to four million miles from the brown dwarf, well within the confines of the disk, according to theory.
But as the brown dwarf cools, Dr. Luhman explained, this zone will sweep in, quickly at first and then ever more slowly. That means that the fate of a planet depends on where it is. A planet in the center of the zone now could look forward to a few tens of millions of years of habitability, he said.
But he added that theorists had no idea how and if such planets would form to begin with. Nor do they know whether life could arise in the brief time allotted.
Other astronomers said it was a little too early to start speculating about life or prebiotic chemistry around a brown dwarf.
Dr. Alan Boss, a planetary theorist at the Carnegie Institution of Washington, said, "The biggest impact of this discovery may be to force theorists to consider the possibility of planet formation around objects which are so low in mass that they are on the verge of being called planets themselves."
It is not too soon, he said, to start worrying about what to call some of these things.
Four years ago, astronomers discovered a dozen or so objects with masses estimated at 5 to 15 Jupiters amid new stars and gas clouds in the Orion nebula. They named them free-floating "planets," to the dismay of most astronomers, who object that planets are things that revolve around stars. A committee of the International Astronomical Union came up instead with the name "sub-brown dwarfs."
The confusion has been compounded lately by the recent "weighing" of a putative brown dwarf in the constellation Doradus, which suggest that some of these cosmic small fry, like brown dwarfs, might be more massive than they look. If this is true, the free-floating planets may actually be brown dwarfs, and some brown dwarfs may actually be small stars.
Dr. Laird Close of the University of Arizona, who made those measurements, said that even given the uncertainty in the brown dwarf's mass, OTS 44 was the smallest object yet found with an infrared excess - and thus probably a circumstellar disk. But in an e-mail message, he cautioned that this did not prove that 15-Jupiter-mass objects could form their own solar systems.
Dr. Boss, chairman of the astronomical union's committee, said, "More classification headaches are likely to ensue as astronomers probe deeper and deeper into the backyards of the Sun's neighborhood."
February 8, 2005
For the Worst of Us, the Diagnosis May Be 'Evil'
By BENEDICT CAREY
redatory killers often do far more than commit murder. Some have lured their victims into homemade chambers for prolonged torture. Others have exotic tastes - for vivisection, sexual humiliation, burning. Many perform their grisly rituals as much for pleasure as for any other reason.
Among themselves, a few forensic scientists have taken to thinking of these people as not merely disturbed but evil. Evil in that their deliberate, habitual savagery defies any psychological explanation or attempt at treatment.
Most psychiatrists assiduously avoid the word evil, contending that its use would precipitate a dangerous slide from clinical to moral judgment that could put people on death row unnecessarily and obscure the understanding of violent criminals.
Still, many career forensic examiners say their work forces them to reflect on the concept of evil, and some acknowledge they can find no other term for certain individuals they have evaluated.
In an effort to standardize what makes a crime particularly heinous, Dr. Michael Welner, an associate professor of psychiatry at New York University, has been developing what he calls a depravity scale, which rates the horror of an act by the sum of its grim details.
And a prominent personality expert at Columbia University has published a 22-level hierarchy of evil behavior, derived from detailed biographies of more than 500 violent criminals.
He is now working on a book urging the profession not to shrink from thinking in terms of evil when appraising certain offenders, even if the E-word cannot be used as part of an official examination or diagnosis.
"We are talking about people who commit breathtaking acts, who do so repeatedly, who know what they're doing, and are doing it in peacetime" under no threat to themselves, said Dr. Michael Stone, the Columbia psychiatrist, who has examined several hundred killers at Mid-Hudson Psychiatric Center in New Hampton, N.Y., and others at Creedmoor Psychiatric Center in Queens, where he consults and teaches. "We know from experience who these people are, and how they behave," and it is time, he said, to give their behavior "the proper appellation."
Western religious leaders, evolutionary theorists and psychological researchers agree that almost all human beings have the capacity to commit brutal acts, even when they are not directly threatened. In Dr. Stanley Milgram's famous electroshock experiments in the 1960's, participants delivered what they thought were punishing electric jolts to a fellow citizen, merely because they were encouraged to do so by an authority figure as part of a learning experiment.
In the real world, the grim images coming out of Iraq -the beheadings by Iraqi insurgents and the Abu Ghraib tortures, complete with preening guards - suggest how much further people can go when they feel justified.
In Nazi prisoner camps, as during purges in Kosovo and Cambodia, historians found that clerks, teachers, bureaucrats and other normally peaceable citizens committed some of the gruesome violence, apparently swept along in the kind of collective thoughtlessness that the philosopher Hannah Arendt described as the banality of evil.
"Evil is endemic, it's constant, it is a potential in all of us. Just about everyone has committed evil acts," said Dr. Robert I. Simon, a clinical professor of psychiatry at Georgetown Medical School and the author of "Bad Men Do What Good Men Dream."
Dr. Simon considers the notion of evil to be of no use to forensic psychiatry, in part because evil is ultimately in the eye of the beholder, shaped by political and cultural as well as religious values. The terrorists on Sept. 11 thought that they were serving God, he argues; those who kill people at abortion clinics also claim to be doing so. If the issue is history's most transcendent savages, on the other hand, most people agree that Hitler and Pol Pot would qualify.
"When you start talking about evil, psychiatrists don't know anything more about it than anyone else," Dr. Simon said. "Our opinions might carry more weight, under the patina or authority of the profession, but the point is, you can call someone evil and so can I. So what? What does it add?"
Dr. Stone argues that one possible benefit of including a consideration of evil may be a more clear-eyed appreciation of who should be removed from society and not allowed back. He is not an advocate of the death penalty, he said. And his interest in evil began long before President Bush began using the word to describe terrorists or hostile regimes.
Dr. Stone's hierarchy of evil is topped by the names of many infamous criminals who were executed or locked up for good: Theodore R. Bundy, the former law school student convicted of killing two young women in Florida and linked to dozens of other killings in the 1970's; John Wayne Gacy of Illinois, the convicted killer who strangled more than 30 boys and buried them under his house; and Ian Brady who, with his girlfriend, Myra Hindley, tortured and killed children in England in a rampage in the 1960's known as the moors murders.
But another killer on the hierarchy is Albert Fentress, a former schoolteacher in Poughkeepsie, N.Y., examined by Dr. Stone, who killed and cannibalized a teenager, in 1979. Mr. Fentress petitioned to be released from a state mental hospital, and in 1999 a jury agreed that he was ready; he later withdrew the petition, when prosecutors announced that a new witness would testify against him.
At a hearing in 2001, Dr. Stone argued against Mr. Fentress's release, and the idea that the killer might be considered ready to make his way back into society still makes the psychiatrist's eyes widen.
Researchers have found that some people who commit violent crimes are much more likely than others to kill or maim again, and one way they measure this potential is with a structured examination called the psychopathy checklist.
As part of an extensive, in-depth interview, a trained examiner rates the offender on a 20-item personality test. The items include glibness and superficial charm, grandiose self-worth, pathological lying, proneness to boredom and emotional vacuity. The subjects earn zero points if the description is not applicable, two points if it is highly applicable, and one if it is somewhat or sometimes true.
The psychologist who devised the checklist, Dr. Robert Hare, a professor emeritus at the University of British Columbia in Vancouver, said that average total scores varied from below five in the general population to the low 20's in prison populations, to a range of 30 to 40 - highly psychopathic - in predatory killers. In a series of studies, criminologists have found that people who score in the high range are two to four times as likely as other prisoners to commit another crime when released. More than 90 percent of the men and a few women at the top of Dr. Stone's hierarchy qualify as psychopaths.
In recent years, neuroscientists have found evidence that psychopathy scores reflect physical differences in brain function. Last April, Canadian and American researchers reported in a brain-imaging study that psychopaths processed certain abstract words - grace, future, power, for example - differently from nonpsychopaths.
In addition, preliminary findings from new imaging research have revealed apparent oddities in the way psychopaths mentally process certain photographs, like graphic depictions of accident scenes, said Dr. Kent Kiehl, an assistant clinical professor of psychiatry at Yale, a lead author on both studies.
No one knows how significant these differences are, or whether they are a result of genetic or social factors. Broken homes and childhood trauma are common among brutal killers; so is malignant narcissism, a personality type characterized not only by grandiosity but by fantasies of unlimited power and success, a deep sense of entitlement, and a need for excessive admiration.
"There is a group we call lethal predators, who are psychopathic, sadistic, and sane, and people have said this is approaching a measure of evil, and with good reason," Dr. Hare said. "What I would say is that there are some people for whom evil acts - what we would consider evil acts - are no big deal. And I agree with Michael Stone that the circumstances and context are less important than who they are."
Checklists, scales, and other psychological exams are not blood tests, however, and their use in support of a concept as loaded as evil could backfire, many psychiatrists say. Not all violent predators are psychopaths, for one thing, nor are most psychopaths violent criminals. And to suggest that psychopathy or some other profile is a reliable measure of evil, they say, would be irresponsible and ultimately jeopardize the credibility of the profession.
In the 1980's and 1990's, a psychiatrist in Dallas earned the name Dr. Death by testifying in court, in a wide variety of cases, that he was certain that defendants would commit more crimes in the future - though often, he had not examined them. Many were sentenced to death.
"I agree that some people cannot be rehabilitated, but the risk in using the word evil is that it may mean one thing to one psychiatrist, and something else to another, and then we're in trouble, " said Dr. Saul Faerstein, a forensic psychiatrist in Beverly Hills. "I don't know that we want psychiatrists as gatekeepers, making life-and-death judgments in some cases, based on a concept that is not medical."
Even if it is used judiciously, other experts say, the concept of evil is powerful enough that it could obscure the mental troubles and intellectual quirks that motivate brutal killers, and sometimes allow them to avoid detection. Mr. Bundy, the serial killer, was reportedly very romantic, attentive and affectionate with his own girlfriends, while he referred to his victims as "cargo" and "damaged goods," Dr. Simon noted.
Mr. Gacy, a gracious and successful businessman, reportedly created a clown figure to lift the spirits of ailing children. "He was a very normal, very functional guy in many respects," said Dr. Richard Rappaport, a forensic psychiatrist based in La Costa, Calif., who examined Mr. Gacy before his trial. Dr. Rappaport said he received holiday cards from Mr. Gacy every year before he was executed.
"I think the main reason it's better to avoid the term evil, at least in the courtroom, is that for many it evokes a personalized Satan, the idea that there is supernatural causation for misconduct," said Dr. Park Dietz, a forensic psychiatrist in Newport Beach, Calif., who examined the convicted serial murderer Jeffrey Dahmer, as well as Lyle and Erik Menendez, who were convicted of murdering their parents in Beverly Hills.
"This could only conceal a subtle important truth about many of these people, such as the high rate of personality disorders," Dr. Dietz said. He added: "The fact is that there aren't many in whom I couldn't find some redeeming attributes and some humanity. As far as we can tell, the causes of their behavior are biological, psychological and social, and do not so far demonstrably include the work of Lucifer."
The doctors who argue that evil has a place in forensics are well aware of these risks, but say that in some cases they are worth taking. They say it is possible - necessary, in fact, to understand many predatory killers - to hold inside one's head many disparate dimensions: that the person in question may be narcissistic, perhaps abused by a parent, or even charming, affectionate and intelligent, but also in some sense evil. While the term may not be appropriate for use in a courtroom or a clinical diagnosis, they say, it is an element of human nature that should not be ignored.
Dr. Angela Hegarty, director of psychiatry at Creedmoor who works with Dr. Stone, said she was skeptical of using the concept of evil but realized that in her work she found herself thinking and talking about it all the time. In 11 years as a forensic examiner, in this country and in Europe, she said, she counts four violent criminals who were so vicious, sadistic and selfish that no other word could describe them.
One was a man who gruesomely murdered his own wife and young children and who showed more annoyance than remorse, more self-pity than concern for anyone else affected by the murders. On one occasion when Dr. Hegarty saw him, he was extremely upset - beside himself - because a staff attendant at the facility where he lived was late in arriving with a video, delaying the start of the movie. The man became abusive, she said: he insisted on punctuality.
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