Eole 01 Spyglass Mountain
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cr Epilogue ~ eole 01 Spyglass Mountain y love of cornets began with a 3-rninute speech I gave in sixth M grade. I think I said that cornets have heads and tails, that they fly about the sun, and maybe even that some people could discover comets. Looking far into the future, I would have said that Halley's comet, the most famous comet of all, wasn't due back for more than a quarter-century. Within a few months, a fortuitous fall off a bicycle and a get well present of a book about the solar system got me firmly single tracked toward the sky. I remember wondering why my little tele scope made everything look like a doughnut; then I realized that if I moved the eyepiece, the telescope would focus. So on the stars were points of light, and Satum became a ball with a ring around it. Glorious! I had seen the rings in pictures, but to see them for myself was thrilling. I was so excited that I called my parents, who came out to look. It took only a few minutes to see this planet with the rings, but I've never forgotten that night. For Dad, watehing me discover Satum's ring brought hirn back to his childhood. One evening over dinner, he told me about a novel he had read when he was a youngster. Called Cole o[ Spyglass Mountain, it was Arthur Preston Hankins' story about a boy whose love of the sky led hirn to observe Mars through his small home- 241 242 ~ Epilogue made teleseope. 1 The novel ended with eole finding evidenee of life on Mars one night and beeoming an instant eelebrity. "If you ever find that book," Dad said, ''I' d like to read it again." Five years later I began my long seareh for eomets. As the years went by and Dad grew older, he would often ask if I had found Cole of Spyglass Mountain. Then with the onset of Alzheimer' s disease, his memory began to fail. As his time grew short, we spent more of it together, and I watehed helplessly as he forgot names, forgot people, and onee even forgot that I was his son. But somehow he never forgot that euphorie story about a boy and a mountaintop that had eaptured his imagination so many years earlier. When I finally found my first eomet in 1984, I feit as though I had rewritten Cole of Spyglass Mountain in a private way just for my father. But Dad was too ill to appreciate it, and he died only a few months later. I will always regret that I eould not share the most signifieant moment in my life with the most important person in it. A few years later, my friend Peter Jedicke found a eopy of Cole of Spyglass Mountain in a library, and I was able to see its words in print for the first time. Dad had remembered them very well, I found. Though spyglass mountain is fiction, it evokes the magie of diseovering new things in the sky. Whether it's a new eomet on its way to a meeting with the sun or the remains of a long-departed one as a erater on the moon, the enehantment re verberates through time as eaeh generation first looks toward the sky and wonders about it. Spyglass mountain didn't turn Dad into an astronomer, but it helped hirn understand what diseovery is like, and I like to think that it helped hirn understand my love of eomets. Sinee then 19 of them have eome my way, and somewhere in the excitement of eaeh one, I remember Dad, his long-gone book, and our first look at the sky together. ~ Afterword ~ How to Discover a Cornet T/ you are serious about comet hunting, you should first learn to recognize l°the different types 0/ /uzzy deep-sky objects like galaxies, clusters, and nebulae, both to avoid mistaking them for comets and because they are interesting in themselves. You will find these in the Messier catalog. Representing every type of deep-sky object, this catalog offers excellent training for a would-be comet hunter. Finding these objects at different times of the year and under varying observing conditions will build the discipline that is needed in comet hunt ing-a skill that does not come ovemight but builds on a special love of the sky. This is more of an invitation to study the Messiers than a waming to stay away from hunting. The Messiers are a cordon bleu of the finest deep-sky objects you can behold-the exquisite wisps of M42, Orion Nebula; the nearest spiral galaxy, M31; the spec tacular globular M13 in Hercules; the Ring Nebula M57; even the mysterious misshapen galaxy M82-this is the grandeur of the Messiers. If you don't find a good proportion of them before you begin a serious comet search, then you are denying yourself the appropriate introduction to what your noctumal hunts could offer. If your study of Messiers gives you an indication of what com ets are not, observing comets that are already present and accounted 243 244 ~ Afterword for will give you an idea of what they are. Vsing positions and descriptions from such sources as the Circulars from the Interna tional Astronomical Vnion's (IAV's) CBAT-the IAV's clearing house for new astronomical discoveries-or from such magazines as Sky and Telescope or Astronomy, keep an eye on the comets you can see with your instrument. You will probably find that most comets, even the ones listed in magazines, are quite faint and dif ficult to observe from light-laden city skies. Patterns of Search Although comet hunting can be done with almost any tele scope, I recommend one that offers a wide-field view of the sky. Comet hunting works best if you follow a definite plan. Moving the telescope slowly, search a small area of the sky thoroughly, for example, rather than a large one haphazardly. You can also expect better results if you search for 1 hour for 10 nights through areas more likely to have comets rather than searching 10 hours on 1 night through sections of the sky far from the sun and unlikely to produce a comet. Since comets shine brightest when they are ne ar the sun, you have a much better chance of finding a new one in the western sky after dusk or in the eastern sky before dawn. Most important, if you really want to find a comet, don't give up on your quest. During the long years before I spotted my first new comet, I took heart from the advice of Robert Burnham, who dis covered several comets during the 1950s and 1960s; he told me that "if you hunt for comets long enough, sooner or later you will find one."l Equipment Required I have used three telescopes for visual comet hunting, an 8- inch, a 6-inch, and a 16-inch reflector. Your telescope needs to be capable of at least a three-quarter degree diameter field of view. Exactly how large the telescope should be depends on a number Afterword ~ 245 of factors: how much money you wish to spend; whether you plan to mount the telescope at a dark site or to carry it around from place to place. The size of your telescope also determines the brightness range of comets you are likely to find. For comets of the eighth magnitude or brighter, a 6-inch telescope will suffice, but such a telescope cannot catch anything much fainter, since the diffuse quality of some comets makes them more difficult to see than clusters and many nebulae of the same brightness. Methods of Hunting There are as many variations in comet-hunting procedures as there are successful comet hunters. My telescopes are a11 mounted on simple altazimuth mounts with motions across and up and down. Canada's Rolf Meier hunts with an equatoria11y mounted telescope, checking suspicious objects quickly from their right as cension and declination. He never overlaps fields, and he searches at the rate of about a degree a second. In Australia, William Brad field makes horizontal sweeps with an altazimuth-mounted tele scope over a wide arc of sky and always in the same direction. On one point most hunters agree: Patience, ski11 and luck are necessary ingredients for a successful comet search. Depending on the peculiarities of your own telescope and its mount, you might try different ways of hunting. You can hunt up and down strips of sky in a zigzag pattern, although this procedure may leave gaps in your search pattern as the setting sky goes past your telescope. You can sweep horizonta11y along a strip that is at some altitude above the horizon, or you can hunt along specific strips of declination or right ascension. The procedure you fo11ow is not nearly so important as making certain that your search area is thoroughly covered. With my 40-centimeter diameter reflector, I hunt in an up-and-down pattern partly because my telescope moves more easily that way than in azimuth as it crosses the sky. When to Hunt for Comets Comet hunting requires some judgment in choosing the best times for sweeping. On successive nights after a fu11 moon, you 246 ~ Afterword will see more and more hours of dark sky. Since the areas dosest to the sun have the best chance of containing an undiscovered comet, begin searching in the western sky in the nights following a full moon.