Starlight Detectives

by Alan Hirshfeld

  More praise for

  STARLIGHT DETECTIVES

  “Hirshfeld documents how the practice of astronomy changed between 1840 and 1940 thanks to innovative pioneers whose efforts made it possible to capture and preserve otherwise faint and fleeting images, and to decipher the cryptographic messages found in the light of celestial bodies. His riveting narrative brings to life their challenges, failures, and successes. It will captivate all who have observed the night sky.” —Barbara J. Becker, author of Unravelling Starlight: William and Margaret Huggins and the Rise of the New Astronomy

  “Writing this book would ideally require an author with an extensive knowledge of astronomy, including astronomical instruments, a deep understanding of the ways of thought of astronomers, a broad range of historical knowledge, and an exceptional skill at making astronomical ideas clear and engaging. Alan Hirshfeld possesses all of these skills. His Starlight Detectives is remarkable.” —Michael J. Crowe, author of The Extraterrestrial Life Debate, 1750–1900

  “A thrilling historical account of the rise of astrophysics, the early years of astronomical photography and spectroscopy, and the innovations that transformed the astronomical telescope in the nineteenth century. Alan Hirshfeld’s thoroughly researched narrative is accessible, entertaining, and scholarly, and includes many pioneers who have been overlooked until now. I greatly admire this outstanding contribution to the history of astronomy.” —Simon Mitton, co-author of Heart of Darkness: Unraveling the Mysteries of the Invisible Universe and author of Fred Hoyle: A Life in Science

  James Nasmyth’s twenty-inch Cassegrain-Newtonian telescope, circa 1845.

  First Published in the United States in 2014 by Bellevue Literary Press, New York

  For Information, Contact:

  Bellevue Literary Press

  NYU School of Medicine

  550 First Avenue

  OBV A612

  New York, NY 10016

  Copyright © 2014 by Alan Hirshfeld

  Library of Congress Cataloging-in-Publication Data is available from the publisher upon request.

  All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system now known or to be invented, without permission in writing from the publisher, except by a reviewer who wishes to quote brief passages in connection with a print, online, or broadcast review.

  Bellevue Literary Press would like to thank all its generous donors—individuals and foundations—for their support.

  Book design and composition by Mulberry Tree Press, Inc.

  first edition

  135798642

  ebook ISBN: 978-1-934137-79-6

  CONTENTS

  Introduction

  Part I: Picturing the Heavens

  1. True Eye and Faithful Hand

  2. The Ingenious Mechanic of Dorchester

  3. Writing with Light

  4. Summits of Silver

  5. The Man with the Oil-Can

  6. The Evangelists

  7. The Aristocrat and the Artisan

  8. Passion Is Good, Obsession Is Better

  9. From Closet to Cosmos

  10. Leaves of Glass

  11. The Grandest Failure

  12. An Uncivil War

  Part II: Seeing the Light

  13. The Odd Couple

  14. What’s My Line?

  15. Laboratories of Light

  16. Deconstructing the Sun

  17. A Strange Cryptography

  18. Trumpets and Telescopes

  19. Burn This Note

  20. A Spectacle of Suns

  21. The Cloud That Wasn’t There

  22. The Union of Two Astronomies

  Part III: Money, Mirrors, and Madness

  23. Mr. Hale of Chicago

  24. The Universe in the Mirror

  25. Threads to a Web

  26. Size Matters

  27. A Night to Remember

  28. Oculis Subjecta Fidelibus

  Epilogue

  References

  Appendices

  Time Line

  Glossary of Names

  Bibliography

  Acknowledgments

  Illustration Sources and Permissions

  Index

  To Erika, who believed in me. Twice.

  The story of scientific discovery has its own epic unity—a unity of purpose and endeavour—the single torch passing from hand to hand through the centuries; and the great moments of science—when, after long labour, the pioneers saw their accumulated facts falling into a significant order, sometimes in the form of a law that revolutionised the whole world of thought—have an intense human interest, and belong essentially to the creative imagination of poetry.

  —Arthur Noyes, Prologue to Watchers of the Sky, 1922

  INTRODUCTION

  LIKE SEAFARERS OF YESTERYEAR, astronomers explore the vast ocean of space, sailing before the winds of imagination and scientific scrutiny. Through their instruments of observation and analysis, they have transformed the night sky from a dark, depthless field studded with glimmering specks and wisps of indeterminate nature into a multidimensional expanse of stars, galaxies, and electromagnetic waves. Under what circumstances did this transition take place? How did classical astronomy mature into its modern form?

  For millennia, astronomers had studied the universe by eye, first without optical aid, then, beginning in the early 1600s, augmented by the telescope. After two centuries of incremental improvements, astronomical instruments were optimized to the needs of celestial cartographers, but were woefully inadequate tools for a meaningful exploration of deep space. The telescope was only part of the problem: the human eye itself was a fundamental roadblock to progress. The eye is an evolutionary artifact, optimized for acuity in the daytime, but ill-suited to the low-light environment of the night sky. It has neither the capacity to accumulate luminous energy over spans of time, nor the ability to delineate a light beam’s constituent wavelengths. The radiance of a celestial object forms an ephemeral, nearly monochromatic image on the observer’s retina. Once an astronomer’s eye drew away from the telescope, no facsimile existed of the cosmic scene, other than an impressionistic précis or pencil-sketch. Until they could generate an objective, permanent record—a photograph—of the object, astronomers remained hostage to the physiological constraints of their eyes and the descriptive limitations of language and art. And until a practical means was developed to distill light into its component colors—a spectrum—the physical processes underlying the glow of a comet, a star, and or a nebula would defy explanation.

  Starlight Detectives explores the decades-long bridge of innovation that transformed Victorian-era visual astronomy into the scientific discipline that is observational astrophysics. It is an inspiring tale of practical dreamers—a clockmaker, a chemist, a printer, a physician, a lawyer, a sanitation engineer, a builder—driven by a common desire to explore the night sky in a profoundly different way. Together with a few forward-thinking professionals, these nineteenth-century apostles of technology spurned the traditional study of the positions and movements of heavenly bodies to hunt down clues regarding their chemical makeup and physical conditions. Through inventiveness and unflagging persistence, they turned their backyard observatories into unlikely centers of cutting-edge astronomy—incubators for the fledgling fields of celestial photography and celestial spectroscopy.

  Over succeeding decades, the observational techniques advanced by these amateur scientists joined with foundational developments in physics—relativity, quantum mechanics, atomic structure—to create a scientific framework that could scarcely have been imagined a centu
ry earlier: the Sun, formerly an impenetrable disk, became a structured, blazing body of chemical elements; the stars, no longer mere gleams of light, became celestial energy factories; and the galaxies, once enigmatic incandescences in the telescope’s eyepiece, became titanic stellar vortices populating the void. In blazing the pathway to a more powerful mode of cosmic observation, amateur astronomers and inventors guided their professional counterparts toward the future, and in doing so found themselves unprepared for its heightened technological and mathematical rigor.

  The work of two astronomers—Ireland’s William Parsons, the Third Earl of Rosse; and American observer Edwin Hubble—effectively serve as “before” and “after” models that make manifest the revolutionary degree to which astronomy changed between the 1840s and the 1920s. Both men surveyed the fringes of the visible universe in their respective times, each employing the largest telescope then in existence: Rosse, his six-foot-wide Leviathan reflector, slung between masonry walls on the grounds of his sprawling estate; and Hubble, the eight-foot-wide Hooker reflector, emplaced high up on Mount Wilson in California.

  William Parsons, the Third Earl of Rosse.

  The Leviathan’s yawning aperture was put to immediate use gathering up the feeble light of celestial nebulae. These mysterious, cloud-like luminescences, thousands in number, appeared in various forms—some round, some oblong, some ragged-bordered. Upon telescopic magnification, many had revealed themselves to be clusters of stars, whose stellar character strained the limits of visual acuity. Astronomers at the time debated whether all nebulae consist of stars, the irresolvable wisps rendered indistinct by virtue of their remoteness. The Leviathan, it was hoped, might prove these distant pockets of efflorescence to be starry as well. While the mammoth telescope did succeed in resolving additional nebulae into stars, this feat was soon overshadowed by a pivotal discovery.

  The Leviathan of Parsonstown.

  In April 1845, Rosse discerned in the faint glow of the nebula Messier 51 an unmistakable, and wholly unexpected, spiral pattern. The Whirlpool Nebula, as it became known, proved far from unique. By 1850, Rosse’s Leviathan had revealed more than a dozen others. Whatever the spirals were, they comprised a populous species within the celestial zoo and demanded further study.

  Although equipped with the largest telescope of the day, Rosse was a prisoner of Victorian-era science; like his fellow observers, he had no basis upon which to comprehend the true character of the celestial objects he viewed. He was leafing though a book of the cosmos, indexing its contents, with no understanding of the book’s meaning. Rosse’s Leviathan was an opto-mechanical dinosaur, successful in its time, but doomed to extinction by its physical bulk, its cloud-swept location, and, most significantly, its allegiance to the human retina. Indeed, every telescope of the era, large or small, was compromised by its dependence on the astronomer’s subjective eye and hand. Even as Rosse limned the dim swirls of the Whirlpool Nebula from his darkened aerie, a new technology was sweeping the world: a photochemical process that recorded images on a metal plate.

  Seven decades later, Edwin Hubble took up the study of spiral nebulae, and proved them to be galaxies on par with our own Milky Way. The contrast between Rosse’s and Hubble’s working methods and their overall understanding of nature illustrates the stark differences between classical visual astronomy and modern astrophysical observation. Rosse perused telescopic images by eye and sketched what he saw, whereas Hubble applied the camera and the spectrograph. Rosse, the wealthy gentleman-scientist, hired local laborers to construct instruments of his own design; Hubble, the salaried scientist, employed equipment under the auspices of an institution. Rosse’s observatory was utterly Victorian in design and execution: a grand assembly of wood, metal, and masonry, set appropriately on a lawn and operated by ropes, pulleys, and handwheels; Hubble’s apparatus was pure industrial chic: a massive steel-girder cylinder, cradled in a steel yoke atop riveted steel piers, hunkered underneath a cavernous, steel-ribbed dome, every movable component electrically driven. Rosse erected his telescope on the grounds of his own home, so it was easily accessible; Hubble’s instrument was laboriously hauled piece by piece up mile-high Mount Wilson in California, trading convenience for the chance of clear skies.

  Rosse’s drawing of the Whirlpool Nebula.

  The Whirlpool Galaxy (née Nebula), photographed by the Hubble Space Telescope in 2005.

  Starlight Detectives is a comprehensive history of this remarkable and complex period in the development of humanity’s oldest science. Its large cast of characters, besides Rosse and Hubble, features many whose names are unfamiliar even to present-day researchers, but whose contributions proved key to the advancement of astronomy. In the following pages, the foundational observations, the technological tweaks, the serendipitous insights, and the cross-fertilization of ideas that precede every momentous discovery are brought into focus. From our latter-day perch, it is easy to wonder why celestial research was so protracted during the nineteenth century. The retrospective lens of time inevitably shrinks once-lofty barriers to progress and straightens the winding route to discovery. Indeed, it was more than fifty years after its introduction that photography became a regular tool of astronomical research; mere decades before the success of spectroscopic analysis, the determination of the constitution of the Sun and stars had been deemed impossible. The constant in this story of an evolving science is the inventiveness and unswerving devotion of those who strove to illuminate the darkness. Their heroic achievements provided the foundation for our modern-day exploration of the universe.

  Part I:

  PICTURING THE HEAVENS

  By applying a sensitive photographic plate to the telescope instead of the human eye, we have obtained photographs of comets, stars, and nebulae which it was utterly impossible for the eye to see through the telescope . . . [T]he cumulative effects of many hours’ exposure reveal depths in our universe undreamed of before.

  —William Seton, “The Century’s Progress in Science,” 1899

  Chapter 1

  TRUE EYE AND FAITHFUL HAND

  There is no one “with a true eye and a faithful hand” but can do good work in watching the heavens.

  —Agnes Clerke, History of Astronomy During the Nineteenth Century, 1902

  ON THE MORNING OF JUNE 16, 1806, the Moon’s shadow crept eastward toward the city of Boston like a gathering herald of an apocalypse. The azure sky, cloudless from horizon to horizon, began to dim, at first almost imperceptibly, then swiftly, as though hastening toward night. Every tree became a living camera obscura, its leafy canopy speckling the ground with a multitude of heavenly crescents. An autumn chill infused the air, raising a mist over the harbor. Birds suspended their song, while on Boston’s grassy common, a herd of cows, sensing the close of day, ambled out of the gateway toward home. Throughout the city, the regular bustle of human commerce quieted to midnight stillness.

  Drawing by Spanish astronomer Joaquin de Ferrer of the solar eclipse of June 16, 1806, as seen from Kinderhook, New York.

  Bostonians were well prepared for the “Great Solar Eclipse,” as some called it. Already, a month beforehand, they had snapped up three printings of Andrew Newell’s fact-filled pamphlet, Darkness at Noon. Newell described how the merged celestial bodies would appear as a “dark patch” in the daytime sky, how precaution must be taken to avoid injury to the eye, how an eclipse of such duration—fully four and a half minutes—might not recur over Boston “for many succeeding ages.” Newell was no man of science, but a lesser printer occupying mean quarters on Half Court Square, off Pudding Lane. Nevertheless, his cobbled tract brought out virtually the entire city onto rooftops, street corners, and quays to witness nature’s once-in-a-lifetime spectacle.

  The few with a spyglass or telescope projected the Sun’s gouged image onto a piece of paper. Those without an instrument observed the progress of the eclipse through a smoked glass plate, or lacking that, chanced a direct view of the diminished Sun. At the onset of totali
ty, the Sun’s corona extended its crepuscular fingers across the ash-tinted sky. Venus blazed like a diamond in the southwest. Reddish Mars popped into view. The winter stars of Orion and Taurus shone incongruously in June. Nothing in recent memory had presented a more sublime sight. “We seemed to be in the more immediate presence of Deity,” remarked an eyewitness.

  Four and a half minutes later, at 11:13 a.m., the Sun re-exploded into view over the Moon’s receding limb. The umbral shadow swept out to sea, and light returned to the land. It was like a second dawn of creation, someone said. Boston’s Columbian Centinel would report that if “angels had been in the habit of visiting this nether world, we justly might have expected them on this transporting occasion.”

  Shouts and applause rose from the city and the surrounding hills. As one, the residents of Boston expressed their gratitude to God, to Nature, to no one in particular for the magnificent interruption in their ordinary existence. They would doubtless recount impressions of this remarkable day to children, to friends. Of course, words and sketches could do only imperfect justice to the celestial tableau now locked away in the private prison of memory. Gifted poets and painters might try to resurrect the all-encompassing wonder of the eclipse, but until accompanied by a true, visual record of the event—a photograph—they would fall short. There was, in 1806, no way to preserve this or any scene for posterity. The only people who could truly comprehend what happened this day were the people who were there.

  No one in Boston could have anticipated the solar eclipse more than sixteen-year-old William Cranch Bond, who reveled in its sheer majesty and the irrepressible cosmic engine at its root. Son of a clockmaker—also named William—Bond had reluctantly left school at age ten to work in his father’s modest shop, at the corner of Milk and Marlborough (later Washington) Streets, across from the Old South Meeting House, where Sam Adams had spurred the Boston Tea Party nearly seven decades before.