QX-DU•telescope\cvrSpread 12/19/05 9:17 AM Page 1 Notice: and right sides that will be folded into the spine, and glued. into the spine, and right sides that will be folded So as to achieve double thick front & back covers. front & back thick double So as to achieve Denver’s Great Telescope additional 5.875” have may Cover panels on both left Denver’s Great Telescope TELESCOPE DENVER’S GREAT By Claire M.By Claire Stencel & Robert E. Stencel This guidebook will introduce you to the University of Denver’s historic Chamberlin Observatory in south Denver, which houses a 20-in. aperture Clark-Saegmuller Refractor type telescope. This telescope, one of the largest of its era, saw first light in July 1894 and is still function- al. Regular classes and public viewing sessions still occur. Astronomy at the University of Denver has remained con- tinuously active since 1880, in the pursuit of research, teaching and community outreach. Please visit the Internet home pages of the University of Denver obser- vatories for more information (http://www.du.edu). Photo by George Beam, 1898 University of Denver Penrose Archives Your Guidebook to the University of Denver’s Historic ISBN#0-9762017-2-0 Chamberlin Observatory By Claire M. Stencel & Robert E. Stencel Glenn E. Montgomery, Editor Cover may have additional 5.875” have may Cover panels on both left first edition, 2006 So as to achieve double thick front & back covers. front & back thick double So as to achieve and right sides that will be folded into the spine, and glued. into the spine, and right sides that will be folded Notice: QX-DU•telescope\cvrSpread 12/19/05 9:17 AM Page 2 Registered Emboss QX-DU•telescope\2 12/19/05 9:06 AM Page 1 DENVER’S GREAT TELESCOPE Denver’s Great Telescope Acknowledgements History is made by many, many people. With apologies to those who played significant roles in bringing this booklet forth but have not been properly credited, we especially thank: Herbert J. and Beverly Howe, Stephen Fisher, Yelena McElwain, Glenn Montgomery, Russ Mellon, Tom Melscheimer, Herschel Neumann, Fran Ohmer, Alyssa Phillips, Hank Rael, Bob Raynolds, Aaron Reid, Hal and Dolly Secrist, Susan Conat Stencel, Barbara and Tom Stephen, David Trott, Barry Winter, William Herschel Womble, Astronomy students at the University of Denver, staff of the University of Denver Physical Plant, Ed Kline, Larry Brooks, Public Night volunteers and officers of the Denver Astronomical Society, the geniuses at Software Bisque, our friends at S&S Optika, the staff at the Denver Museum of Nature & Science Gates Planetarium, Don Asquin, clockmak- ers Al Baumbach and Bill Dillon, University Park Neighbors, reporters John Ensslin, Ann Schrader, Warren Smith and Joseph Verrengia, and many other individuals who have contributed in one way or another over the many years to the survival of the University of Denver’s historic Chamberlin Observatory. Kindly bring concerns for any errors of fact or omission in this text to the attention of the authors for correction in a subsequent edition. Photos are largely from the DU Penrose Archives, the Howe family or newly imaged by the authors unless credited differently, insofar as is possible. This book is dedicated to Mr. Glenn E. Montgomery, whose sustained inter- est in astronomy at the University of Denver is cause for cheers. We appre- ciate his financial underwriting and publication of this book and the pro- ceeds of its sale for the observatory. To him and all involved in sustaining Denver’s grand telescope, our thanks and a heartfelt “Hipp, Hipp, Hoorah!” Denvers’s Great Telesope By Claire M. Stencel & Robert E. Stencel Editor and publisher: Glenn E. Montgomery Graphics and design: Bob Stewart, BASS Creative, Aurora, Colorado Publication coordinator: Mari Gaylord ISBN#0-9762017-2-0 Copyright ©2006 Astronomy Program, University of Denver All rights reserved. No part of this book may be reproduced in any manner or transmitted by any means whatsoever, electronic or mechanical (including photocopy, film or video recording, Internet posting, or any other information storage and retrieval system) without the prior writ- ten permission of the publisher. For information about this book, see page 96 Printed in Hong Kong through Global Interprint, Santa Rosa, California. QX-DU•telescope\2 12/19/05 9:06 AM Page 2 DENVER’S GREAT TELESCOPE A GUIDEBOOK TO THE HISTORIC CHAMBERLIN OBSERVATORY Table of Contents Acknowledgements SIGNFICANT OTHERS. 55 Mr. Chamberlin’s Story INTRODUCTION . 5 Dr. Howe’s Story The Telescope, Introduced and Illustrated Donald Menzel The Telescope’s Journey to Denver Albert Recht Overall Length,Width, Height and Other Interesting Facts The Denver Astronomical Society Telescope Vitals Edgar Everhart Aperture and Focal Length Robert Stencel Types of Telescopes Purchasing a Telescope ACTIVITIES AND PROGRAMS . 73 Observatory Programs in Howe’s Time ORIGINS . 19 Howe’s Solution to the Kepler Problem Chamberlin Offers to Build an Observatory Howe’s Study of Asteroids and Comets Making the Lens, Alvan Clark’s Story The Great Fireball of 1900 The Telescope Mounting, George Saegmuller’s Story Surveying - One of Howe’s Many Talents Observatory Programs After Howe TELESCOPE MACHINERY - STATIC PARTS . 24 Attendance Figures Over Time The Pier The Struggle With Lighting Pollution The “Tripod” The Future of the Observatory The Cast Iron Pillar Endowment TELESCOPE MACHINERY - MOVING PARTS. 28 APPENDICES . 88 The Equatorial Head Sources & Citations The Clock Drive Deed Creating Observatory Park The Dome Publications of Herbert Alonso Howe More Clocks & Dials Chamberlin Observatory Construction Chronology Focal Plane Instruments Additional Information Finder Telescopes Befriend the Observatory The Observing Ladder The Transit Telescope Library Maintenance Notes ARCHITECTURAL NOTES AND POINTS OF INTEREST. 42 Design Story Form and Function Roeschlaub The Land Around the Observatory The Student Observatory 2 3 QX-DU•telescope\2 12/19/05 9:07 AM Page 4 CHAPTER ONE Introduction “Astronomy serves the following The Telescope and Observatory, Introduced and Illustrated The Telescope’s Journey to Denver needs: to encourage the habit of Overall Length,Width, Height and Other Interesting Facts Telescope Vitals accurate observation; to Aperture and Focal Length Types of Telescopes strengthen reasoning by the Purchasing a Telescope application of mathematics to astronomical phenomena, and its pure disciplinary value of lifting the mind from daily cares, to the contemplation of awe-inspiring grandeur and majestic laws that bind countless worlds into one harmonious whole, providing order and beauty out of apparent chaos.” —Professor Howe, First Director, Chamberlin Observatory QX-DU•telescope\2 12/19/05 9:07 AM Page 6 DENVER’S GREAT TELESCOPE CHAPTER ONE: INTRODUCTION Opposite Page The Telescope - Introduced and Illustrated The Chamberlin Observatory telescope, a 20-inch Clark At the heart of the University of Denver’s historic Chamberlin Observatory lies Saegmuller refractor, was among the largest of its the telescope, a 20-in. aperture Clark-Saegmuller Refractor. The telescope kind at time of first saw light in July of 1894, and is still used by scientists, students and vis- construction. The telescope - aimed north itors today. It is among the largest of its kind still in use in the United States. and seen from the west In this guidebook, we will explore some of the facets of this great Refractor side of the dome room - telescope, tell stories about some of the people behind it, and explore the past saw first light in 1894, and is still used today by and future of the University of Denver’s historic Chamberlin Observatory. students, teachers and visitors. Shown in the similar cover photo is The observatory is named after its patron, Humphrey B. Chamberlin, who the telescope and pledged $50,000 in 1888 to see it built and equipped. Professor Herbert A. Professor Herbert Howe, the man responsible for Howe, the astronomer at the University of Denver at that time, was responsi- the design of and ble for overall design, instrument specification and installation. Alvan Clark instrument installation at the observatory. & Sons of Cambridge, Mass., the foremost opticians of the day, crafted the © Courtesy of University lenses for the telescope. When it was made, the primary lens was priced at of Denver Penrose $1,000. Today, it is considered priceless. The mechanical mounting for the Archives telescope was built by George N. Saegmuller, who owned and operated Fauth and Company instrument makers in Washington DC. Humphrey Chamberlin was active in the Denver real estate business at the time, so Saegmuller and Clark both accepted land holdings as part of their payment. However, when the great Silver Panic of 1893 caused the bottom to drop out of the landowning business, Mr. Chamberlin went bankrupt and the properties offered to Saegmuller and Clark rapidly declined in value. Professor Howe paid Clark with his own cash and compensated Saegmuller by delaying delivery of his finished telescope for a time, personally assisting with its display at the Chicago Columbian Exposition of 1893. The telescope components and lenses were finally shipped to Denver by 1894. Howe was concerned for the safety of the 150-lb. lenses, so he personally transported it from Cambridge to Denver in a private train car. Howe performed final assembly of the telescope at Chamberlin Observatory, in addition to his duties as Dean and professor at DU. The University assist- ed as much as it could in paying Clark and Saegmuller, but Howe had to pay some of the fees out of his own pocket. Trial observations began on July 14, 1894, with “first light.” This initial use of the telescope by Howe included observations of stars in the famed cluster M13 in Hercules and Earth’s moon. The first public use of the telescope occurred on August 1 of the same year, when Howe entertained the Swedish Methodist Christian Endeavor Society with a look at Saturn.