6A70.23 - Telescopes - Refractors and Reflectors

Code Number:
6A70.23
Demo Title:
Telescopes - Refractors and Reflectors
Condition:
Good
Principle:
Lens Systems and Focal Lengths
Area of Study:
Optics
Equipment:
Refractor Telescopes, 14 Inch Reflector Telescope with Plexiglas Body, 6 Inch Plexiglas Demo Reflecting Telescope, Galileoscope, Spyglass Variable Length Telescopes, and Tasco Telescope.
Procedure:

See also 8D20.40 in Astronomy.

The refractors and 14 inch reflector telescopes are mainly for show and tell as their focal lengths do not allow you to see images of any object inside the classroom.

The Galileoscope and the Spyglass telescopes are ready to go at a moments notice.  You will need to adjust the length on each telescope to bring your viewing object into focus.  This adjustment will be critical when trying to image something in the Lecture Rooms.

References:
  • Kendra Sibbernsen, "Electronic Telescopes and Their Use In Astronomy Education", TPT, Vol. 60, #5, May 2022, p. 394.
  • Christopher M. Graney, "Objects in Telescope are Farther Than They Appear", TPT, Vol. 47, #6, Sept. 2009, p. 362.
  • David P. Stern, "Sundials and Compasses", TPT, Vol. 41, #7, Oct. 2003, p. 380.
  • Harry Manos, "Galileo's Lens", TPT, Vol. 41, #5, May 2003, p. 268.
  • A. J. Cox and Alan J. DeWeerd, "The Image Between the Lenses: Activities with a Telescope and a Microscope", TPT, Vol. 41, #3, Mar. 2003, p. 176.
  • David Chandler, "Understanding Parabolic Reflectors Through Paper Folding", TPT, Vol. 39, #1, Jan. 2001, p. 24.
  • Thomas B. Greenslade Jr., "The Rosse Telescope", TPT, Vol. 36, #8, Nov. 1998, p. 493.
  • Thomas D. Miner, "In Your Eye", TPT, Vol. 27, #2, Feb. 1989, p. 70.
  • M. Eugene Rudd, "The Rainbow and the Achromatic Telescope: Two Case Studies", TPT, Vol. 26, #2, Feb. 1988, p. 82.
  • Kenneth N. Taylor, "Measuring Focal Lengths and Principal Planes of Complex Lens", TPT, Vol. 25, #8, Nov. 1987, p. 484.
  • William Blunk and Arnold Burkert, "A Telescope Workshop", TPT, Vol. 25, #2, Feb. 1987, p. 111.
  • Thomas B. Greenslade Jr., "Nineteenth Century Textbook Illustrations - XLV", TPT, Vol. 24, #4, Apr. 1986, p. 228.
  • Carl C. Sartain, "More on Galileo's Telescopes", TPT, Vol. 20, #6, Sept. 1982, p. 352.
  • Thomas E. Ruden, "Galileo's First Telescopes?", TPT, Vol. 20, #3, Mar. 1982, p. 140.
  • G. Daniel Goehring, "Galileo's First Telescopes", TPT, Vol. 19, #8, Nov. 1981, p. 516.
  • Michael K. Gainer, "Construction of a 17th Century Telescope: An Experiment in the History of Astronomy", TPT, Vol. 19, #1, Jan. 1981, p. 22.
  • Thomas B. Greenslade, Jr., "Rosse Telescope", AJP, Vol. 80, #6, June 2012, p. 496.
  • J. Robert Waaland, "Fraunhofer and the Great Dorpat Refractor", AJP, Vol. 35, #4, Apr. 1967, p. 344.
  • Toni Feder, "Behemoth Telescopes Build Toward First Light", Physics Today, Vol. 68, #8, Aug. 2015, p. 24.
  • Toni Feder, "New Telescope in Turkey", Physics Today, Vol. 24, #10, Oct. 2014, p. 26.
  • Christian B. Luginbuhl, Constance E. Walker, and Richard J. Wainscoat, "Lighting and Astronomy", Physics Today, Vol. 62, #12, Dec. 2009, p. 32.
  • Theo ten Brummelaar, Michelle Creech-Eakman, and John Monnier, "Probing Stars with Optical and Near-IR Interferometry", Physics Today, Vol. 62, #6, June 2009. p. 28.
  • Toni Feder, "Limiting Light Pollution is Ongoing Challenge", Physics Today, Vol. 58, #6, June 2005, p. 24.
  • Toni Feder, "Mercury Telescope Spins Up", Physics Today, Vol. 56, #11, Nov. 2003, p. 24.
  • Govert Schilling, "Lens Array Captures Dim Objects Missed by Giant Telescopes", Science, Vol. 371, # 6536, March 26, 2021, p. 1301.
  • C. L. Stong,  "The Amateur Scientist: Concerning the Problem of Making Sharper Photographs of the Planets", Scientific American, Vol. 194, #6, June 1956, p. 156.
  • Béla Szomi Kralj, "DIY Enables Affordable Lessons in Light", Physics Education, Vol. 40, #4, July 2005, p. 320.
  • Chris F. Linas, "Building a Telescope", The Science Teacher, Vol. 55, #9, Dec. 1988, p. 33.
  • Justin Nobel, "How to Make a Telescope", Popular Mechanics, Vol. 193, #8, Sept. 2016, p. 72.
  • Cameron Johnson, "How to Get Started in Astronomy", Popular Mechanics, Vol. 193, #1, Dec/Jan. 2016, p. 55.
  • Michael Koziol, "How to Build a DIY Replica of Galileo's Telescope", Popular Science, Vol. 289, #1, Jan/Feb. 2017, p. 77.
  •  Daniel Engber, "Which is More Powerful: A Giant Microscope or a Giant Telescope", Popular Science, Vol. 288, Vol. #1, Jan/Feb 2016, p. 100.
  • Alexandra Ossola, "These Next-Gen Telescopes Will Peer Into The Deep History Of The Universe", Popular Science, Vol. 287, #1, Jan. 2015, p. 30.
  • Wallace A. Hilton, "G-1", Experiments in Optical Physics, p. 6.
  • George M. Hopkins, "The Telescope", Experimental Science, p. 309.
  • John Henry Pepper, "Mr. Browning's Description of the Silvered Glass Reflecting Telescopes", Cyclopadic Science Simplified, p. 41.
  • Rick Beyer, "The Music Man", The Greatest Science Stories Never Told, p. 28.
  • Rick Beyer, "Lippershey's Looker", The Greatest Science Stories Never Told, p. 12.
  • Dick Suiter, "Test Drive Your Telescope", Supplement to Astronomy, Sept. 1990.
  • James P. Wells, "Annals of a University of Iowa Department", Natural Philosophy to Physics and Astronomy, June 1980.
  • Janice VanCleave, "Fill 'Er Up", Help, My Science Project is Due Tomorrow!, p. 20.
  • Michael D. Lemonick, "From Here to Eternity", Discover, May 1999, p. 50 - 55.
  • Raymond Bruman, "Telescope", Exploratorium Cookbook I, p. 13.1 - 13.2.
  • "Using a Telescope", International Masters Publishers.
  • Eric Adams, "Light and Magic", 2002 Science Supplement, ISBN 0-7172-1571-7, p. 64.
  • D. Tattersfield, "9.1. Telescopes", Project & Demonstrations in Astronomy, p. 224.
  • "Magnifying Power and Resolving Power of a Telescope", Selective Experiments in Physics, CENCO, 1962.
  • "Simple Telescopes - Magnifying Power", Selective Experiments in Physics, CENCO, 1962.
  • Curt Suplee, "Focusing on Worlds Near and Far", Everyday Science Explained, National Geographic, p. 110 - 111.
  • Joseph Frick, "#184 - The Telescope", Physical Technics: Or Practical Instructions for Making Experiments in Physics and the Construction of Physical Apparatus with the Most Limmited Means, p. 215.
  • Dr. Gordon Stables, R.N., C. Stansfeld Hicks, J. N. Maskelyne, Rev. Harry Jones, M.A, Dr. Stradling, Captain Crawley, Rev. A. n. Malan, M.A., F.G.S., and Many Others, "Chapter XXXIX - How to Make an Astronomical Telescope", The Boy's Own Book of  Indoor Games and Recreations, A Popular Encyclopaedia for Boys, p. 380.
  • Editors of Portable Press, "Seeing Clearly", Strange Science, p. 401.
  • "The Astronomic Telescope on Brass Stand", Pike's Illustrated Catalogue of Scientific & Medical Instruments, 1984, p. 118.

Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.