Death By Black Hole Part 14

Sn.o.bby people from other countries like to make fun of the U.S. for its abbreviated history and its uncouth culture, particularly compared with the millennial legacies of Europe, Africa, and Asia. But 500 years from now historians will surely see the twentieth century as the American century-the one in which American discoveries in science and technology rank high among the world's list of treasured achievements.

Obviously the U.S. has not always sat atop the ladder of science. And there's no guarantee or even likelihood that American preeminence will continue. As the capitals of science and technology move from one nation to another, rising in one era and falling in the next, each culture leaves its mark on the continual attempt of our species to understand the universe and our place in it. When historians write their accounts of such world events, the traces of a nation's presence on center stage sit prominently in the timeline of civilization.

MANY FACTORS INFLUENCE how and why a nation will make its mark. Strong leadership matters. So does access to resources. But something else must be present-something less tangible, but with the power to drive an entire nation to focus its emotional, cultural, and intellectual capital on creating islands of excellence in the world. Those who live in such times often take for granted what they have created, on the blind a.s.sumption that things will continue forever as they are, leaving their achievements susceptible to abandonment by the very culture that created it. how and why a nation will make its mark. Strong leadership matters. So does access to resources. But something else must be present-something less tangible, but with the power to drive an entire nation to focus its emotional, cultural, and intellectual capital on creating islands of excellence in the world. Those who live in such times often take for granted what they have created, on the blind a.s.sumption that things will continue forever as they are, leaving their achievements susceptible to abandonment by the very culture that created it.

Beginning in the 700s and continuing for nearly 400 years-while Europe's Christian zealots were disemboweling heretics-the Abbasid caliphs created a thriving intellectual center of arts, sciences, and medicine for the Islamic world in the city of Baghdad. Muslim astronomers and mathematicians built observatories, designed advanced timekeeping tools, and developed new methods of mathematical a.n.a.lysis and computation. They preserved the extant works of science from ancient Greece and elsewhere and translated them into Arabic. They collaborated with Christian and Jewish scholars. And Baghdad became a center of enlightenment. Arabic was, for a time, the lingua franca of science.

The influence of these early Islamic contributions to science remains to this day. For example, so widely distributed was the Arabic translation of Ptolemy's magnum opus on the geocentric universe (originally written in Greek in A.D A.D. 150), that even today, in all translations, the work is known by its Arabic t.i.tle Almagest, Almagest, or "The Greatest." or "The Greatest."

The Iraqi mathematician and astronomer Muhammad ibn Musa al-Khwarizmi gave us the words "algorithm" (from his name, al-Khwarizmi) and "algebra" (from the word al-jabr al-jabr in the t.i.tle of his book on algebraic calculation). And the world's shared system of numerals-0, 1, 2, 3, 4, 5, 6, 7, 8, 9-though Indian in origin, were neither common nor widespread until Muslim mathematicians exploited them. The Muslims furthermore made full and innovative use of the zero, which did not exist among Roman numerals or in any established numeric system. Today, with legitimate reason, the ten symbols are internationally referred to as Arabic numerals. in the t.i.tle of his book on algebraic calculation). And the world's shared system of numerals-0, 1, 2, 3, 4, 5, 6, 7, 8, 9-though Indian in origin, were neither common nor widespread until Muslim mathematicians exploited them. The Muslims furthermore made full and innovative use of the zero, which did not exist among Roman numerals or in any established numeric system. Today, with legitimate reason, the ten symbols are internationally referred to as Arabic numerals.

PORTABLE, ORNATELY ETCHED, bra.s.s astrolabes were also developed by Muslims, from ancient prototypes, and became as much works of art as tools of astronomy. An astrolabe projects the domed heavens onto a flat surface and, with layers of rotating and nonrotating dials, resembles the busy, ornate face of a grandfather clock. It enabled astronomers, as well as others, to measure the positions of the Moon and the stars on the sky, from which they could deduce the time-a generally useful thing to do, especially when it's time to pray. The astrolabe was so popular and influential as a terrestrial connection to the cosmos that, to this day, nearly two-thirds of the brightest stars in the night sky retain their Arabic names.

The name typically translates into an anatomical part of the constellation being described. Famous ones on the list (along with their loose translations) include: Rigel (Al Rijl, "foot") and Betelgeuse ( "foot") and Betelgeuse (Yad al Jauza, "hand of the great one"-in modern times drawn as the armpit), the two brightest stars in the constellation Orion; Altair ( "hand of the great one"-in modern times drawn as the armpit), the two brightest stars in the constellation Orion; Altair (At-Ta'ir, "the flying one"), the brightest star in the constellation Aquila, the eagle; and the variable star Algol ( "the flying one"), the brightest star in the constellation Aquila, the eagle; and the variable star Algol (Al-Ghul, "the ghoul"), the second brightest star in the constellation Perseus, referring to the blinking eye of the b.l.o.o.d.y severed head of Medusa held aloft by Perseus. In the less-famous category are the two brightest stars of the constellation Libra, athough identified with the scorpion in the heyday of the astrolabe: Zubenelgenubi ( "the ghoul"), the second brightest star in the constellation Perseus, referring to the blinking eye of the b.l.o.o.d.y severed head of Medusa held aloft by Perseus. In the less-famous category are the two brightest stars of the constellation Libra, athough identified with the scorpion in the heyday of the astrolabe: Zubenelgenubi (Az-Zuban al-Janubi, "southern claw") and Zebueneschamali ( "southern claw") and Zebueneschamali (Az-Zuban ash-Shamali, "northern claw"), the longest surviving star names in the sky. "northern claw"), the longest surviving star names in the sky.

At no time since the eleventh century has the scientific influence of the Islamic world been equal to what it enjoyed the preceding four centuries. The late Pakistani physicist Abdus Salam, the first Muslim ever to win the n.o.bel Prize, lamented: There is no question [that] of all civilizations on this planet, science is the weakest in the lands of Islam. The dangers of this weakness cannot be overemphasized since honorable survival of a society depends directly on strength in science and technology in the conditions of the present age. (Ha.s.san and Lui 1984, p. 231) (Ha.s.san and Lui 1984, p. 231)

PLENTY OF OTHER nations have enjoyed periods of scientific fertility. Think of Great Britain and the basis of Earth's system of longitude. The prime meridian is the line that separates geographic east from west on the globe. Defined as zero degrees longitude, it bisects the base of a telescope at an observatory in Greenwich, a London borough on the south bank of the River Thames. The line doesn't pa.s.s through New York City. Or Moscow. Or Beijing. Greenwich was chosen in 1884 by an international consortium of longitude mavens who met in Washington, DC, for that very purpose. nations have enjoyed periods of scientific fertility. Think of Great Britain and the basis of Earth's system of longitude. The prime meridian is the line that separates geographic east from west on the globe. Defined as zero degrees longitude, it bisects the base of a telescope at an observatory in Greenwich, a London borough on the south bank of the River Thames. The line doesn't pa.s.s through New York City. Or Moscow. Or Beijing. Greenwich was chosen in 1884 by an international consortium of longitude mavens who met in Washington, DC, for that very purpose.

By the late nineteenth century, astronomers at the Royal Greenwich Observatory-founded in 1675 and based, of course, in Greenwich-had acc.u.mulated and catalogued a century's worth of data on the exact positions of thousands of stars. The Greenwich astronomers used a common but specially designed telescope, constrained to move along the meridional arc that connects due north to due south through the observer's zenith. By not tracking the general east to west motion of the stars, they simply drift by as Earth rotates. Formally known as a transit instrument, such a telescope allows you to mark the exact time a star crosses your field of view. Why? A star's "longitude" on the sky is the time on a sidereal clock the moment the star crosses your meridian. Today we calibrate our watches with atomic clocks, but back then there was no timepiece more reliable than the rotating Earth itself. And there was no better record of the rotating Earth than the stars that pa.s.sed slowly overhead. And n.o.body measured the positions of pa.s.sing stars better than the astronomers at the Royal Greenwich Observatory.

During the seventeenth century Great Britain had lost many ships at sea due to the challenges of navigation that result from not knowing your longitude with precision. In an especially tragic disaster in 1707, the British fleet, under Vice Admiral Sir Clowdesley Shovell, ran aground into the Scilly Isles, west of Cornwall, losing four ships and 2,000 men. With enough impetus, England finally commissioned a Board of Longitude, which offered a fat cash award-20,000-to the first person who could design an ocean-worthy chronometer. Such a timepiece was destined to be important in both military and commercial ventures. When synchronized with the time at Greenwich, such a chronometer could determine a ship's longitude with great precision. Just subtract your local time (readily obtained from the observed position of the Sun or stars) from the chronometer's time. The difference between the two is a direct measure of your longitude east or west of the prime meridian.

In 1735, the Board of Longitude's challenge was met by a portable, palm-sized clock designed and built by an English mechanic, John Harrison. Declared to be as valuable to the navigator as a live person standing watch at a ship's bow, Harrison's chronometer gave renewed meaning to the word "watch."

Because of England's sustained support for achievements in astronomical and navigational measurements, Greenwich landed the prime meridian. This decree fortuitously placed the international date line (180 degrees away from the prime meridian) in the middle of nowhere, on the other side of the globe in the Pacific Ocean. No country would be split into two days, leaving it beside itself on the calendar.

IF THE ENGLISH have forever left their mark on the spatial coordinates of the globe, our basic temporal coordinate system-a solar-based calendar-is the product of an investment of science within the Roman Catholic Church. The incentive to do so was not driven by cosmic discovery itself but by the need to keep the date for Easter in the early spring. So important was this need that Pope Gregory XIII established the Vatican Observatory, staffing it with erudite Jesuit priests who tracked and measured the pa.s.sage of time with unprecedented accuracy. By decree, the date for Easter had been set to the first Sunday after the first full moon after the vernal equinox (preventing Holy Thursday, Good Friday, and Easter Sunday from ever falling on a special day in somebody else's lunar-based calendar). That rule works as long as the first day of spring stays in March, where it belongs. But the Julian calendar of Julius Caesar's Rome was sufficiently inaccurate that by the sixteenth century it had acc.u.mulated 10 extra days, placing the first day of spring on April 1 instead of March 21. The four-year leap day, a princ.i.p.al feature of the Julian calendar, had slowly overcorrected the time, pushing Easter later and later in the year. have forever left their mark on the spatial coordinates of the globe, our basic temporal coordinate system-a solar-based calendar-is the product of an investment of science within the Roman Catholic Church. The incentive to do so was not driven by cosmic discovery itself but by the need to keep the date for Easter in the early spring. So important was this need that Pope Gregory XIII established the Vatican Observatory, staffing it with erudite Jesuit priests who tracked and measured the pa.s.sage of time with unprecedented accuracy. By decree, the date for Easter had been set to the first Sunday after the first full moon after the vernal equinox (preventing Holy Thursday, Good Friday, and Easter Sunday from ever falling on a special day in somebody else's lunar-based calendar). That rule works as long as the first day of spring stays in March, where it belongs. But the Julian calendar of Julius Caesar's Rome was sufficiently inaccurate that by the sixteenth century it had acc.u.mulated 10 extra days, placing the first day of spring on April 1 instead of March 21. The four-year leap day, a princ.i.p.al feature of the Julian calendar, had slowly overcorrected the time, pushing Easter later and later in the year.

In 1582, when all the studies and a.n.a.lyses were complete, Pope Gregory deleted the 10 offending days from the Julian calendar and decreed the day after October 4 to be October 15. The Church thenceforth made an adjustment: for every century year not evenly divisible by 400, a leap day gets omitted that would otherwise have been counted, thus correcting for the overcorrecting leap day itself.

This new "Gregorian" calendar was further refined in the twentieth century to become even more precise, preserving the accuracy of your wall calendar for tens of thousands of years to come. n.o.body else had ever kept time with such precision. Enemy states of the Catholic Church (such as Protestant England, and its rebellious progeny, the American colonies) were slow to adopt the change, but eventually everyone in the civilized world, including cultures that traditionally relied on Moon-based calendars, adopted the Gregorian calendar as the standard for international business, commerce, and politics.

EVER SINCE THE BIRTH of the industrial revolution the European contributions to science and technology have become so embedded in Western culture that it may take a special effort to step outside and notice them at all. The revolution was a breakthrough in our understanding of energy, enabling engineers to dream up ways to convert it from one form to another. In the end, the revolution would serve to replace human power with machine power, drastically enhancing the productivity of nations and the subsequent distribution of wealth around the world. of the industrial revolution the European contributions to science and technology have become so embedded in Western culture that it may take a special effort to step outside and notice them at all. The revolution was a breakthrough in our understanding of energy, enabling engineers to dream up ways to convert it from one form to another. In the end, the revolution would serve to replace human power with machine power, drastically enhancing the productivity of nations and the subsequent distribution of wealth around the world.

The language of energy is rich with the names of those scientists who contributed to the effort. James Watt, the Scottish engineer who perfected the steam engine in 1765, has the moniker best known outside the circles of engineering and science. Either his last name or his monogram gets stamped on the top of practically every lightbulb. A bulb's wattage measures the rate it consumes energy, which correlates with its brightness. Watt worked on steam engines while at the University of Glasgow, which was, at the time, one of the world's most fertile centers for engineering innovation.

The English physicist Michael Faraday discovered electromagnetic induction in 1831, which enabled the first electric motor. The farad, a measure of a device's capacity to store electric charge, probably doesn't do full justice to his contributions to science.

The German physicist Heinrich Hertz discovered electromagnetic waves in 1888, which enabled communication via radio; his name survives as the unit of frequency along with its metric derivatives "kilohertz," "megahertz," and "gigahertz."

From the Italian physicist Alessandro Volta we have the volt, a unit of electric potential. From the French physicist Andre-Marie Ampere, we have the unit of electric current known as the ampere, or "amp" for short. From the British physicist James Prescott Joule, we have the joule, a unit of energy. The list goes on and on.

With the exception of Benjamin Franklin and his tireless experiments with electricity, the U.S. as a nation watched this fertile chapter of human achievement from afar, preoccupied with gaining its independence from England and exploiting the economies of slave labor. Today the best we could do was pay homage in the original Star Trek Star Trek television series: Scotland is the country of origin of the industrial revolution, and of the chief engineer of the starship television series: Scotland is the country of origin of the industrial revolution, and of the chief engineer of the starship Enterprise Enterprise. His name? "Scotty" of course.

In the late eighteenth century the industrial revolution was in full swing, but so too was the French Revolution. The French used the occasion to shake up more than the royalty; they also introduced the metric system to standardize what was then a world of mismatched measures-confounding science and commerce alike. Members of the French Academy of Sciences led the world in measures of the Earth's shape and had proudly determined it to be an oblate spheroid. Building on this knowledge, they defined the meter to be one ten-millionth the distance along the Earth's surface from the North Pole to the equator, pa.s.sing through-where else?-Paris. This measure of length was standardized as the separation between two marks etched on a special bar of platinum alloyed with iridium. The French devised many other decimal standards that (except for decimal time and decimal angles) were ultimately adopted by all the civilized nations of the world except the U.S., the west African nation of Liberia, and the politically unstable tropical nation of Myanmar. The original artifacts of this metric effort are preserved at the International Bureau of Weights and Measures-located, of course, near Paris.

BEGINNING IN THE late 1930s the U.S. became a nexus of activity in nuclear physics. Much of the intellectual capital grew out of the exodus of scientists from n.a.z.i Germany. But the financial capital came from Washington, in the race to beat Hitler to build an atomic bomb. The coordinated effort to produce the bomb was known as the Manhattan Project, so named because much of the early research had been done in Manhattan, at Columbia University's Pupin Laboratories. late 1930s the U.S. became a nexus of activity in nuclear physics. Much of the intellectual capital grew out of the exodus of scientists from n.a.z.i Germany. But the financial capital came from Washington, in the race to beat Hitler to build an atomic bomb. The coordinated effort to produce the bomb was known as the Manhattan Project, so named because much of the early research had been done in Manhattan, at Columbia University's Pupin Laboratories.

The wartime investments had huge peacetime benefits for the community of nuclear physicists. From the 1930s through the 1980s, American accelerators were the largest and most productive in the world. These racetracks of physics are windows into the fundamental structure and behavior of matter. They create beams of subatomic particles, accelerate them to near the speed of light with a cleverly configured electric field, and smash them into other particles, busting them to smithereens. Sorting through the smithereens, physicists have found evidence for h.o.a.rds of new particles and even new laws of physics.

American nuclear physics labs are duly famous. Even people who are physics-challenged will recognize the top names: Los Alamos; Lawrence Livermore; Brookhaven; Lawrence Berkeley; Fermi Labs; Oak Ridge. Physicists at these places discovered new particles, isolated new elements, informed a nascent theoretical model of particle physics, and collected n.o.bel Prizes for doing so.

The American footprint in that era of physics is forever inscribed at the heavy end of the periodic table. Element number 95 is americium; number 97 is berkelium; number 98 is californium; number 103 is lawrencium, for Ernest O. Lawrence, the American physicist who invented the first particle accelerator; and number 106 is seaborgium, for Glenn T. Seaborg, the American physicist whose lab at the University of California, Berkeley, discovered ten new elements heavier than uranium.

EVER-LARGER ACCELERATORS reach ever-higher energies, probing the fast-receding boundary between what is known and unknown about the universe. The big bang theory of cosmology a.s.serts that the universe was once a very small and very hot soup of energetic subatomic particles. With a super-duper particle-smasher, physicists might be able to simulate the earliest moments of the cosmos. In the 1980s, when U.S. physicists proposed just such an accelerator (eventually dubbed the Super-conducting Super Collider), Congress was ready to fund it. The U.S. Department of Energy was ready to oversee it. Plans were drawn up. Construction began. A circular tunnel 50 miles around (the size of the Washington, DC, beltway) was dug in Texas. Physicists were eager to peer across the next cosmic frontier. But in 1993, when cost overruns looked intractable, a fiscally frustrated Congress permanently withdrew funds for the $11 billion project. It probably never occurred to our elected representatives that by canceling the Super Collider they surrendered America's primacy in experimental particle physics. reach ever-higher energies, probing the fast-receding boundary between what is known and unknown about the universe. The big bang theory of cosmology a.s.serts that the universe was once a very small and very hot soup of energetic subatomic particles. With a super-duper particle-smasher, physicists might be able to simulate the earliest moments of the cosmos. In the 1980s, when U.S. physicists proposed just such an accelerator (eventually dubbed the Super-conducting Super Collider), Congress was ready to fund it. The U.S. Department of Energy was ready to oversee it. Plans were drawn up. Construction began. A circular tunnel 50 miles around (the size of the Washington, DC, beltway) was dug in Texas. Physicists were eager to peer across the next cosmic frontier. But in 1993, when cost overruns looked intractable, a fiscally frustrated Congress permanently withdrew funds for the $11 billion project. It probably never occurred to our elected representatives that by canceling the Super Collider they surrendered America's primacy in experimental particle physics.

If you want to see the next frontier, hop a plane to Europe, which seized the opportunity to build the world's largest particle accelerator and stake a claim of its own on the landscape of cosmic knowledge. Known as the Large Hadron Collider, the accelerator will be run by the European Center for Particle Physics (better known by an acronym that no longer fits its name, CERN). Although some U.S physicists are collaborators, America as a nation will watch the effort from afar, just as so many nations have done before.

THIRTY-EIGHT.

LET THERE BE DARK.

Astrophysics reigns as the most humbling of scientific disciplines. The astounding breadth and depth of the universe deflates our egos daily, and we are continually at the mercy of uncontrolled forces. A simple cloudy evening-one that would stop no other human activity-prevents us from making observations with a telescope that can cost $20,000 a night to run, regardless of the weather. We are pa.s.sive observers of the cosmos, acquiring data when, where, and how nature reveals it to us. To know the cosmos requires that we have windows onto the universe that remain unfogged, untinted, and unpolluted. But the spread of what we call civilization, and the a.s.sociated ubiquity of modern technology, is generally at odds with this mission. Unless we do something about it, people will soon bathe Earth in a background glow of light, blocking all access to the frontiers of cosmic discovery.

The most obvious and prevalent form of astropollution comes from streetlamps. All too often, they can be seen from your airplane window during night flights, which means that these streetlamps illuminate not only the streets below but the rest of the universe. Unshielded streetlights, such as those without downward-facing shades, are most to blame. Munic.i.p.alities with these poorly designed lamp housings find themselves buying higher-wattage bulbs because half the lamplight points upward. This wasted light, shot forth into the night sky, has rendered much of the world's real estate unsuitable for astronomical research. At the 1999 "Preserving the Astronomical Sky" symposium, partic.i.p.ants rightly moaned about the loss of dark skies around the globe. One paper reported that inefficient lighting costs the city of Vienna $720,000 annually; London $2.9 million; Washington, DC, $4.2 million; and New York City $13.6 million (Sullivan and Cohen 1999, pp. 36368). Note that London, with a population similar to that of New York City, is more efficient in its inefficiency by nearly a factor of 5.

The astrophysicist's quandary is not that light escapes into s.p.a.ce but that the lower atmosphere supports a mixture of water vapor, dust, and pollutants that bounce some of the upward-flowing photons back down to Earth, leaving the sky aglow with the signature of a city's nightlife. As cities become brighter and brighter, dim objects in the cosmos become less and less visible, severing urban dwellers' access to the universe.

It's hard to exaggerate the magnitude of this effect. A penlight's beam, aimed at a wall across a darkened dining room, is easy to spot. But gradually brighten the overhead light, and watch how the beam gets harder and harder to see. Under light-polluted skies, fuzzy objects such as comets, nebulae, and galaxies become difficult or impossible to detect. I have never in my life seen the Milky Way galaxy from within the limits of New York City, and I was born and raised here. If you observe the night sky from light-drenched Times Square, you might see a dozen or so stars, compared with the thousands that were visible from the same spot when Peter Stuyvesant was hobbling around town. No wonder ancient peoples shared a culture of sky lore, whereas modern peoples, who know nothing of the night sky, instead share a culture of evening TV.

The expansion of electrically lit cities during the twentieth century created a technology fog that forced astronomers to move their hilltop observatories from the outskirts of towns to remote places such as the Canary Islands, the Chilean Andes, and Hawaii's Mauna Kea. One notable exception is Kitt Peak National Observatory in Arizona. Instead of running away from the spreading and brightening city of Tucson, 50 miles away, the astronomers stayed and fought. The battle is easier won than you might think; all you have to do is convince people that their choice of outdoor lighting is a waste of money. In the end, the city gets efficient streetlamps and the astronomers get a dark sky. Ordinance No. 8210 of the Tucson/Pima County Outdoor Lighting Code reads as though the mayor, the chief of police, and the prison warden were all astronomers at the time the code was pa.s.sed. Section 1 identifies the intent of the ordinance: The purpose of this Code is to provide standards for outdoor lighting so that its use does not unreasonably interfere with astronomical observations. It is the intent of this Code to encourage, through the regulation of the types, kinds, construction, installation, and uses of outdoor electrically powered illuminating devices, lighting practices and systems to conserve energy without decreasing safety, utility, security, and productivity while enhancing nighttime enjoyment of property within the jurisdiction.

And after 13 other sections that give strict rules and regulations governing citizens' choice of outdoor lighting, we get to the best part, section 15: It shall be a civil infraction for any person to violate any of the provisions of this Code. Each and every day during which the violation continues shall const.i.tute a separate offense.

As you can see, by shining light on an astronomer's telescope you can turn a peace-loving citizen into a Rambo. Think I'm joking? The International Dark-Sky a.s.sociation (IDA) is an organization that fights upward-pointing light anywhere in the world. With an opening phrase reminiscent of the one painted on Los Angeles Police Department squad cars, the IDA's motto says it all: "To preserve and protect the nighttime environment and our heritage of dark skies through quality outdoor lighting." And, like the police, the IDA will come after you if you transgress.

I know. They came after me. Not a week after the Rose Center for Earth and s.p.a.ce first opened its doors to the public, I received a letter from the IDA's executive director, scolding me for the upward-pointing lights embedded in the pavement of our entrance plaza. We were justly accused-the plaza does have forty (very low wattage) lamps that help delineate and illuminate the Rose Center's granite-clad arched entryway. These lights are partly functional and partly decorative. The point of the letter was not to blame the bad viewing conditions across all of New York City on these itty-bitty lamps but to hold the Hayden Planetarium accountable for setting a good example for the rest of the world. I am embarra.s.sed to say that the lights remain.

But all that's bad is not artificial. A full Moon is bright enough to reduce the number of stars visible to the unaided eye from thousands to hundreds. Indeed, the full Moon is more than 100,000 times brighter than the brightest nighttime stars. And the physics of reflection angles endows the full Moon with more than ten times the brightness of a half Moon. This moonglow also greatly reduces the number of meteors visible during a meteor shower (though clouds would be worse), no matter where you are on Earth. So never wish a full Moon upon an astronomer who is headed off to a big telescope. True, the Moon's tidal force created tide pools and other dynamic habitats that contributed to the transition from marine to terrestrial life and ultimately made it possible for humans to thrive. Apart from this detail, most observational astronomers, especially cosmologists, would be happy if the Moon had never existed.

A few years ago I got a phone call from a marketing executive who wanted to light up the Moon with the logo of her company. She wanted to know how she might proceed. After slamming down the phone, I called her back and politely explained why it was a bad idea. Other corporate executives have asked me how to put into orbit mile-wide luminous banners with catchy slogans written across them, much like the skywriting or flag-dragging airplanes you see at sports events or over the ocean from a crowded beach. I always threaten to send the light police after them.

Modern life's insidious link with light pollution extends to other parts of the electromagnetic spectrum. Next at risk is the astronomer's radio-wave window to the cosmos, including microwaves. In modern times we are awash in the signals of such radio waveemitting devices as cellular telephones, garage-door openers, keys that trigger "boip" sounds as they remotely lock and unlock car doors, microwave relay stations, radio and television transmitters, walkie-talkies, police radar guns, Global Positioning Systems, and satellite communications networks. Earth's radio-wave window to the universe lies cloaked in this technologically induced fog. And the few clear bands that remain within the radio spectrum are getting progressively narrower as the trappings of high-tech living grab more and more radio-wave real estate. The detection and study of extremely faint celestial objects is being compromised as never before.

In the past half-century radio astronomers discovered remarkable things, including pulsars, quasars, molecules in s.p.a.ce, and the cosmic microwave background, the first evidence in support of the big bang itself. But even a wireless conversation can drown such faint radio signals: modern radio telescopes are so sensitive that a cell-phone encounter between two astronauts on the Moon would be one of the brightest sources in the radio sky. And if Martians used cell phones, our most powerful radio telescopes would easily nab them, too.

The Federal Communications Commission is not unmindful of the heavy, often conflicting demands that various segments of society place on the radio spectrum. The FCC's Spectrum Policy Task Force intends to review the policies that govern use of the electromagnetic spectrum, with the goal of improving efficiency and flexibility. FCC chairman Michael K. Powell told the Washington Post Washington Post (June 19, 2002) that he wanted the FCC's philosophy to shift from a "command and control" approach to a "market-oriented" one. The commission will also review how it allocates and a.s.signs bands of the radio spectrum, as well as how one allocation may interfere with another. (June 19, 2002) that he wanted the FCC's philosophy to shift from a "command and control" approach to a "market-oriented" one. The commission will also review how it allocates and a.s.signs bands of the radio spectrum, as well as how one allocation may interfere with another.

For its part, the American Astronomical Society, the professional organization of the nation's astrophysicists, has called on its members to be as vigilant as the IDA folks-a posture I endorse-in trying to convince policy makers that specially identified radio frequencies should be left clear for astronomers' use. To borrow vocabulary and concepts from the irrepressible Green movement, these bands should be considered a kind of "electromagnetic wilderness" or "electromagnetic national park." To eliminate interference, the geographic areas surrounding the protected observatories should also be kept clear of human-generated radio signals of any kind.

The most challenging problem may be that the farther an object is from the Milky Way, the longer the wavelength and the lower the frequency of its radio signals. This phenomenon, which is a cosmological Doppler effect, is the princ.i.p.al signature of our expanding universe. So it's not really possible to isolate a single range of "astro" frequencies and a.s.sert that the entire cosmos, from nearby galaxies to the edge of the observable universe, can be served through this window. The struggle continues.

Today, the best place to build telescopes for exploring all parts of the electromagnetic spectrum is the Moon. But not on the side that faces Earth. Putting them there might be worse than looking out from Earth's surface. When viewed from the Moon's near side, Earth looks thirteen times bigger, and shines some fifty times brighter, than the Moon does when viewed from Earth. And Earth never sets. As you might suspect, civilization's chattering communication signals also make Earth the brightest object in the radio-wave sky. The astronomer's heaven is, instead, the Moon's far side, where Earth never rises, remaining forever buried below the horizon.

Without a view of Earth, telescopes built on the Moon could point in any skyward direction, without the risk of contamination from Earth's electromagnetic emanations. Not only that, night on the Moon lasts nearly 15 Earth days, which would enable astronomers to monitor objects in the sky for days on end, much longer than they can from Earth. And because there is no lunar atmosphere, observations conducted from the Moon's surface would be as good as observations of the cosmos from Earth orbit. The Hubble s.p.a.ce Telescope Hubble s.p.a.ce Telescope would lose the bragging rights it now enjoys. would lose the bragging rights it now enjoys.

Furthermore, without an atmosphere to scatter sunlight, the Moon's daytime sky is almost as dark as its night, so everybody's favorite stars hover visibly in the sky, right alongside the disk of the Sun. A more pollution-free place has yet to be found.

On second thought, I retract my earlier callous remarks about the Moon. Maybe our neighbor in s.p.a.ce will one day become the astronomer's best friend after all.

THIRTY-NINE.

HOLLYWOOD NIGHTS.

Few things are more annoying to avid moviegoers than being accompanied to a film by hyperliterate friends who can't resist making comments about why the book was better. These people babble on about how the characters in the novel were more fully developed or how the original story line was more deeply conceived. In my opinion, they should just stay home and leave the rest of us to enjoy the film. For me, it's purely a matter of economics: to see a movie is cheaper and faster than to buy and read the book on which it was based. With this anti-intellectual att.i.tude, I ought to be mute every time I notice scientific transgressions in a movie's story or set design. But I am not. On occasion, I can be as annoying as bookworms to other moviegoers. Over the years, I have collected especially egregious errors in Hollywood's attempts to show or engage the cosmos. And I can no longer keep them to myself.

My list, by the way, does not consist of bloopers. A blooper is a mistake that the producers or continuity editors happen to miss, but normally catch and fix. The astro-errors I'm talking about were willingly introduced and indicate a profound lack of attention to easily checkable detail. I would further a.s.sert that none of these writers, producers, or directors ever took Astronomy 101 in college.

Let's start at the bottom.

At the end of the 1977 Disney film Black Hole, Black Hole, which sits on many people's 10 worst movies list (including mine), an H. G. Wellsian s.p.a.ceship loses control of its engines and plunges into a black hole. What more could special-effects artists ask for? Let's see how well they did. Was the craft and its crew ripped apart by the ever-increasing tidal forces of gravity-something a real black hole would do to them? No. Was there any attempt to portray relativistic time dilation, as predicted by Einstein, where the universe around the doomed crew evolves rapidly over billions of years while they, themselves, age only a few ticks of their wrist.w.a.tches? No. The scene did portray a swirling disk of accreted gas around the black hole. Good. Black holes do this sort of thing with gas that falls toward them. But did elongated jets of matter and energy spew forth from each side of the accretion disk? No. Did the ship travel through the black hole and get spit out into another time? another part of the universe? or in another universe altogether? No. Instead of capturing these cinematically fertile and scientifically informed ideas, the storytellers depicted the black hole's innards as a dank cave, with fiery stalagmites and stalact.i.tes, as though we were touring Carlsbad Cavern's hot and smoky bas.e.m.e.nt. which sits on many people's 10 worst movies list (including mine), an H. G. Wellsian s.p.a.ceship loses control of its engines and plunges into a black hole. What more could special-effects artists ask for? Let's see how well they did. Was the craft and its crew ripped apart by the ever-increasing tidal forces of gravity-something a real black hole would do to them? No. Was there any attempt to portray relativistic time dilation, as predicted by Einstein, where the universe around the doomed crew evolves rapidly over billions of years while they, themselves, age only a few ticks of their wrist.w.a.tches? No. The scene did portray a swirling disk of accreted gas around the black hole. Good. Black holes do this sort of thing with gas that falls toward them. But did elongated jets of matter and energy spew forth from each side of the accretion disk? No. Did the ship travel through the black hole and get spit out into another time? another part of the universe? or in another universe altogether? No. Instead of capturing these cinematically fertile and scientifically informed ideas, the storytellers depicted the black hole's innards as a dank cave, with fiery stalagmites and stalact.i.tes, as though we were touring Carlsbad Cavern's hot and smoky bas.e.m.e.nt.

Some people may think of these scenes as expressions of the director's poetic or artistic license, allowing him to invent whimsical cosmic imagery without regard to the real universe. But given how lame the scenes were, they are more likely to have been an expression of the director's scientific ignorance. Suppose there were such a thing as "scientific license," where a scientist, doing art, chooses to ignore certain fundamentals of artistic expression. Suppose that whenever scientists drew a woman they gave her three b.r.e.a.s.t.s, seven toes on each foot, and an ear in the middle of her face? In a less extreme example, suppose scientists drew people with the knee joint bending the wrong way, or with odd proportions among the body's long bones? If this did not start a new movement in artistic expression-akin to Pica.s.so's flounderlike renderings of the human face-then artists would surely tell us all to go back to school immediately and take some art cla.s.ses in basic anatomy.

Was it license or ignorance that led the painter of a work in the Louvre to draw a cul-de-sac surrounded by erect trees, each with a Sun-made shadow pointing in toward the center of the circle? Hadn't the artist ever noticed that all shadows cast by the Sun on vertical objects are parallel? Is it license or ignorance that nearly every Moon ever painted by artists is either a crescent or a full moon? Half of any month the Moon's phase is neither crescent nor full. Did the artists paint what they saw or what they wished they had seen? When Francis Ford Coppola's 1987 Someone to Watch Over Me Someone to Watch Over Me was being filmed, his cinematographer called my office to ask when and where was the best occasion to film the full Moon rising over the Manhattan skyline. When I instead offered him the first quarter moon or the waxing gibbous moon, he was unimpressed. Only the full Moon would do. was being filmed, his cinematographer called my office to ask when and where was the best occasion to film the full Moon rising over the Manhattan skyline. When I instead offered him the first quarter moon or the waxing gibbous moon, he was unimpressed. Only the full Moon would do.

Although I rant, there's no doubt that creative contributions from the world's artists would be poorer in the absence of artistic license. Among other losses, there would have been no impressionism or cubism. But what distinguishes good artistic license from bad is whether the artist acquired access to all relevant information before the creativity begins. Perhaps Mark Twain said it best: Get your facts first, and then you can distort 'em as much as you please. (1899, Vol. 2, Chap. x.x.xVII) (1899, Vol. 2, Chap. x.x.xVII) In the 1997 blockbuster movie t.i.tanic t.i.tanic, producer and director James Cameron not only invested heavily in special effects but also in re-creating the ship's luxurious interiors. From the wall sconces to the patterns on the china and silverware, no detail of design was too small to attract the attention of Mr. Cameron, who made sure to reference the latest artifacts salvaged from missions to the sunken ship, more than two miles undersea. Furthermore, he carefully researched the history of fashion and social mores to ensure that his characters dressed and behaved in ways generally consistent with the year 1912. Aware that the ship was designed with only three of its four smoke stacks connected to engines, Cameron accurately portrays smoke coming from only three stacks. We know from accurate records of this maiden voyage from Southampton to New York City the date and time the ship sank, as well as the longitude and lat.i.tude on Earth where it sank. Cameron captures that too.

With all this attention to detail, you think James Cameron might have paid a bit more attention to which stars and constellations were visible on that fateful night.

He didn't.

In the movie, the stars above the ship bear no correspondence to any constellations in a real sky. Worse yet, while the heroine bobs and hums a tune on a slab of wood in the freezing waters of the North Atlantic, she stares straight up and we are treated to her view of this Hollywood sky-one where the stars on the right half of the scene trace the mirror image of the stars in the left half. How lazy can you get? To get it right would not have required a major realignment of the film's budget.

What's odd is that n.o.body would have known whether Cameron captured his plate and silverware patterns accurately. Whereas for about fifty bucks you can buy any one of a dozen programs for your home computer that will display the real sky for any time of day, any day of the year, any year of the millennium, and for any spot on Earth.

On one occasion, however, Cameron exercised artistic license commendably. After the t.i.tanic t.i.tanic sank, you see countless people (dead and alive) floating in the water. Of course, on this moonless night in the middle of the ocean, you would barely see the hand in front of your face. Cameron had to add illumination so that the viewer could follow the rest of the story. The lighting was soft and sensible, without obvious shadows indicating an embarra.s.sing (and nonexistent) source of light. sank, you see countless people (dead and alive) floating in the water. Of course, on this moonless night in the middle of the ocean, you would barely see the hand in front of your face. Cameron had to add illumination so that the viewer could follow the rest of the story. The lighting was soft and sensible, without obvious shadows indicating an embarra.s.sing (and nonexistent) source of light.

This story actually has a happy ending. As many people know, James Cameron is a modern-day explorer, who does, in fact, value the scientific enterprise. His undersea expedition to the t.i.tanic t.i.tanic was one of many he has launched, and he served for many years on NASA's high-level Advisory Council. During a recent occasion in New York City, when he was honored by was one of many he has launched, and he served for many years on NASA's high-level Advisory Council. During a recent occasion in New York City, when he was honored by Wired Wired magazine for his adventurous spirit, I was invited to dinner with the editors and Cameron himself. What better occasion to tell him of his errant ways with the magazine for his adventurous spirit, I was invited to dinner with the editors and Cameron himself. What better occasion to tell him of his errant ways with the t.i.tanic t.i.tanic sky. So after I whined for ten minutes on the subject, he replied, "The film, worldwide, has grossed over a billion dollars. Imagine how much more money it would have made had I gotten the night sky correct!" sky. So after I whined for ten minutes on the subject, he replied, "The film, worldwide, has grossed over a billion dollars. Imagine how much more money it would have made had I gotten the night sky correct!"

I have never before been so politely, yet thoroughly, silenced. I meekly returned to my appetizer, mildly embarra.s.sed for having raised the issue. Two months later, a phone call comes to my planetarium office. It was a computer visualization expert from a post-production unit for James Cameron. He said that for their reissue of the film t.i.tanic t.i.tanic, in a Special Collector's Edition, they would be restoring some scenes and he was told I may have an accurate night sky they might want to use for this edition. Sure enough, I generated the right image of the night sky for every possible direction that Kate Winslet and Leonardo DiCaprio could turn their heads while the ship sank.

THE ONLY TIME I ever bothered to compose a letter complaining about a cosmic mistake was after I saw the 1991 romantic comedy I ever bothered to compose a letter complaining about a cosmic mistake was after I saw the 1991 romantic comedy L.A. Story, L.A. Story, written and produced by Steve Martin. In this film, Martin uses the Moon to track time by showing its phase progressing from crescent to full. A big deal is not made of this fact. The Moon just hangs there in the sky from night to night. I applaud Martin's effort to engage the universe in his plot line, but this Hollywood moon grew in the wrong direction. Viewed from any location north of Earth's equator (Los Angeles qualifies), the Moon's illuminated surface grows from right to left. written and produced by Steve Martin. In this film, Martin uses the Moon to track time by showing its phase progressing from crescent to full. A big deal is not made of this fact. The Moon just hangs there in the sky from night to night. I applaud Martin's effort to engage the universe in his plot line, but this Hollywood moon grew in the wrong direction. Viewed from any location north of Earth's equator (Los Angeles qualifies), the Moon's illuminated surface grows from right to left.

When the Moon is a thin crescent, you can find the Sun 20 or 30 degrees to its right. As the Moon orbits Earth, the angle between it and the Sun grows, allowing more and more of its visible surface to be lit, reaching 100 percent frontal illumination at 180 degrees. (This monthly Earth-Sun-Moon configuration is known as syzygy, which reliably gives you a full Moon and, occasionally, a lunar eclipse.) Steve Martin's moon grew from left to right. It grew backward. My letter to Mr. Martin was polite and respectful, written on the a.s.sumption that he would want to know the cosmic truth. Alas, I received no reply, but then again, I was only in graduate school at the time, without a weighty letterhead to grab his attention.

Even the 1983 macho test-pilot epic The Right Stuff The Right Stuff had plenty of the wrong stuff. In my favorite transgression, Chuck Yeager, the first to fly faster than the speed of sound, is shown ascending to 80,000 feet, setting yet another alt.i.tude and speed record. Ignoring the fact that the scene takes place in California's Mojave Desert, where clouds of any species are rare, as Yeager darts through the air you see puffy, white, alto-c.u.mulus clouds whizzing by. This error would surely irk meteorologists because, in Earth's real atmosphere, these clouds would not be caught dead above 20,000 feet. had plenty of the wrong stuff. In my favorite transgression, Chuck Yeager, the first to fly faster than the speed of sound, is shown ascending to 80,000 feet, setting yet another alt.i.tude and speed record. Ignoring the fact that the scene takes place in California's Mojave Desert, where clouds of any species are rare, as Yeager darts through the air you see puffy, white, alto-c.u.mulus clouds whizzing by. This error would surely irk meteorologists because, in Earth's real atmosphere, these clouds would not be caught dead above 20,000 feet.

Without those visual props, I suppose the viewer would have no visceral idea of how fast the plane was moving. So I understand the motive. But the film's director, Philip Kaufman, was not without choices: Other kinds of clouds, such as cirrus, and the especially beautiful noctilucent clouds, do exist at very high alt.i.tudes. At some point in your life you have to learn that they exist.

The 1997 film Contact Contact, inspired by Carl Sagan's 1983 novel of the same name, contains an especially embarra.s.sing astro-gaffe. (I saw the movie and never read the book. But everyone who has read the book says, of course, that it's better than the movie.) Contact Contact explores what might happen when humans find intelligent life in the galaxy and then establish contact with it. The heroine astrophysicist and alien hunter is actress Jodie Foster, who recites a fundamental line that contains mathematically impossible information. Just as she establishes her love interest in ex-priest Matthew McConaughey, seated with the largest radio telescope in the world behind them, she says to him with pa.s.sion: "If there are 400 billion stars in the galaxy, and just one in a million had planets, and just one in a million of those had life, and just one in a million of those had intelligent life, that still leaves millions of planets to explore." Wrong. According to her numbers, that leaves 0.0000004 planets with intelligent life on them, which is a figure somewhat lower than "millions." No doubt that "one in a million" sounds better on screen than "one in ten," but you can't fake math. explores what might happen when humans find intelligent life in the galaxy and then establish contact with it. The heroine astrophysicist and alien hunter is actress Jodie Foster, who recites a fundamental line that contains mathematically impossible information. Just as she establishes her love interest in ex-priest Matthew McConaughey, seated with the largest radio telescope in the world behind them, she says to him with pa.s.sion: "If there are 400 billion stars in the galaxy, and just one in a million had planets, and just one in a million of those had life, and just one in a million of those had intelligent life, that still leaves millions of planets to explore." Wrong. According to her numbers, that leaves 0.0000004 planets with intelligent life on them, which is a figure somewhat lower than "millions." No doubt that "one in a million" sounds better on screen than "one in ten," but you can't fake math.

Ms. Foster's recitation was not a gratuitous expression of math, it was an explicit recognition of the famous Drake equation, named for Astronomer Frank Drake who first calculated the likelihood of finding intelligent life in the galaxy based on a sequence of factors, starting with the total number of stars in the galaxy. For this reason, it was one of the most important scenes in the film. Who do we blame for the flub? Not the screenwriters, even though their words were spoken verbatim. I blame Jodie. As the lead actress, she forms the last line of defense against errors that creep into the lines she delivers. So she must bear some responsibility. Not only that, last I checked, she was a graduate of Yale University. Surely they teach arithmetic there.

During the 1970s and 1980s, the popular television soap opera As The World Turns As The World Turns portrayed sunrise during the opening credits and sunset during the closing credits, which, given the show's t.i.tle, was a suitable cinematic gesture. Unfortunately, their sunrise was a sunset filmed in reverse. n.o.body took the time to notice that for every day of the year in the Northern Hemisphere the Sun moves at an angle up and to the right of the spot on the horizon where it rises. At the end of the day, it descends across the sky at an angle down and to the right. The soap-opera sunrise showed the Sun moving toward the left as it rose. They obviously had gotten a piece of film showing a sunset and played it in reverse for the show's beginning. The producers were either too sleepy to wake up early and film the sunrise, or the sunrise was filmed in the Southern Hemisphere-after which the camera crew ran to the Northern Hemisphere to film sunset. Had they called their local astrophysicists, any one of us might have recommended that if they needed to save money, they could have shown the sunset in a mirror before they showed it running backward. This would have taken care of everybody's needs. portrayed sunrise during the opening credits and sunset during the closing credits, which, given the show's t.i.tle, was a suitable cinematic gesture. Unfortunately, their sunrise was a sunset filmed in reverse. n.o.body took the time to notice that for every day of the year in the Northern Hemisphere the Sun moves at an angle up and to the right of the spot on the horizon where it rises. At the end of the day, it descends across the sky at an angle down and to the right. The soap-opera sunrise showed the Sun moving toward the left as it rose. They obviously had gotten a piece of film showing a sunset and played it in reverse for the show's beginning. The producers were either too sleepy to wake up early and film the sunrise, or the sunrise was filmed in the Southern Hemisphere-after which the camera crew ran to the Northern Hemisphere to film sunset. Had they called their local astrophysicists, any one of us might have recommended that if they needed to save money, they could have shown the sunset in a mirror before they showed it running backward. This would have taken care of everybody's needs.

Of course, inexcusable astro-illiteracy extends beyond television, film, and paintings at the Louvre. The famous star-studded ceiling of New York City's Grand Central Terminal rises high above the countless busy commuters. I would be gripeless if the original designers had no pretense of portraying an authentic sky. But this three-acre canvas contains among its several hundred stars a dozen real constellations, each traced in their cla.s.sical splendor, with the Milky Way flowing by, just where you're supposed to find it. Holding aside the sky's greenish color, which greatly resembles that of Sears household appliances from the 1950s, the sky is backward. Yes, backward. Turns out, this was common practice during the Renaissance, back when globe makers made celestial spheres. But in those cases, you, the viewer, stood in a mythical place "outside" of the sky, looking down, with Earth imagined to occupy the globe's center. This argument works well for spheres smaller than you, but fails miserably for 130-foot ceilings. And amid the backwardness, for reasons I have yet to divine, the stars of the constellation Orion are positioned forward, with Betelgeuse and Rigel correctly oriented.

Astrophysics is surely not the only science trod upon by underinformed artists. Naturalists have probably logged more gripes than we have. I can hear them now: "That's the wrong whale song for the species of whale they showed in the film." "Those plants are not native to that region." "Those rock formations have no relation to that terrain." "The sounds made by those geese are from a species that flies nowhere near that location." "They would have us believe it's the middle of the winter yet that maple tree still has all its leaves."

In my next life, what I plan to do is open a school for artistic science, where creative people can be accredited in their knowledge of the natural world. Upon graduating, they would be allowed to distort nature only in informed ways that advance their artistic needs. As the credits roll by, the director, producer, set designer, cinematographer, and whoever else was accredited would proudly list their membership with Sc.i.p.aL, the Society for Credible Infusion of Poetic and Artistic License.