DEPARTMENT OF ASTROPHYSICAL AND PLANETARY SCIENCES ASTR 1010 Laboratory Introduction to Astronomy Fall 2011 University of Colorado at Boulder Acknowledgements The 1010 laboratory manual originated in the experiments compiled and developed over many years by Dr. Roy Garstang for the APAS 121/122 labs. In 1987 Dr. Garstang published the Sommers-Bausch Observatory Manual of General Astronomy Projects. A number of his 88 exercises were adapted for use in the new APAS 101 (now ASTR 1010) course that was initiated in 1988. Since that time the manual has undergone considerable evolution and expansion under the guidance of faculty lab instructors, including Drs. Raul Stern, Scott Roberston, Larry Esposito, John Stocke, J. McKim Malville, Ted Snow, Fran Bagenal, Nick Schneider, Bob Pappalardo, Brian Hynek, Doug Duncan, and Seth Hornstein. The Kepler’s Laws simulator is part of the Planetary Orbit Simulator Module of the Nebraska Astronomy Applet Project. Supporting materials can be found at http://astro.unl.edu. Virtually every teaching assistant who has conducted a lab in the APAS/APS/ ASTR 121/122/101/1010/1030 series has contributed to this manual by identifying areas of difficulty, making suggestions for improvements, or providing ideas that germinated into new experiments. Some recent major contributors from previous quarters include Mary Urquhart, Travis Rector, Kelsey Johnson, Amanda Sickafoose, Cori Krauss, John Weiss, James Roberts, Margaret Mitter, Colin Wallace, Joseph Parker, and Seth Jacobson. Keith Gleason Seth Hornstein August 2011 Front Cover: Comet Hale-Bopp over the Flatirons courtesy Niescja Turner and Carter Emmart Back Cover: CCD Mosaic of the Full Moon contributed by Keith Gleason ASTR 1010 Astronomy Lab 3 3 TABLE OF CONTENTS GENERAL INFORMATION ................................................................................ 4 CELESTIAL CALENDAR Fall 2011 ..............................................................................10 UNITS AND CONVERSIONS .........................................................................................13 SCIENTIFIC NOTATION ................................................................................................18 MATH REVIEW ...............................................................................................................21 ASTRONOMICAL WEBSITES .......................................................................................26 DAYTIME LABORATORY EXPERIMENTS .................................................. 27 PRELAB QUESTIONS .....................................................................................................29 THE COLORADO MODEL SOLAR SYSTEM ..............................................................31 MOTIONS OF THE SUN .................................................................................................41 MOTIONS OF THE MOON ✩ .........................................................................................47 THE ERATOSTHENES CHALLENGE ...........................................................................55 KEPLER'S LAWS .............................................................................................................63 COLLISIONS, SLEDGEHAMMERS, & IMPACT CRATERS .....................................67 TELESCOPE OPTICS ......................................................................................................81 SPECTROSCOPY I – Light & Color ✩ ............................................................................93 SPECTROSCOPY II – Spectral Barcodes ✩ ..................................................................101 THE SEASONS ...............................................................................................................109 DETECTING EXTRASOLAR PLANETS .....................................................................119 NIGHTTIME OBSERVING PROJECTS ........................................................ 125 CONSTELLATION AND BRIGHT STAR IDENTIFICATION ★ ...............................127 TELESCOPE OBSERVING ★ .......................................................................................131 OBSERVING LUNAR FEATURES ★ ..........................................................................139 ★ - Clear skies are required for this exercise ✩ - Clear skies are needed for a portion of the exercise 4 ASTR 1010 Astronomy Lab 4 General Information GENERAL INFORMATION You must enroll for both the lecture section and a laboratory section. Your lecture section will usually be held in the classroom in Duane Physics Building (just south of Folsom Stadium). An occasional lecture may be held instead at the Fiske Planetarium (at the intersection of Regent Drive and Kittridge Loop; see map below). Your laboratory section will meet once per week during the daytime in Room S175 at Sommers-Bausch Observatory (just east of the Fiske Planetarium). Follow the walkway around the south side of Fiske and up the hill to the Observatory. You will also have nighttime observing sessions using the Sommers-Bausch Observatory telescopes to view and study the constellations, the moon, planets, stars, and other celestial objects. Folsom Engineering Street Center Folsom Events Stadium Colorado Center Avenue Business DUANE PHYSICS Regent Colorado Scale (CLASSROOMS) Drive Model Solar System GAMOW TOWER CDSS (APAS OFFICE) SOMMERS-BAUSCH OBSERVATORY JILA Tower Hallet FISKE Willard PLANETARIUM 18th Street Kittridge Regent MATERIALS The following materials are needed: • ASTR 1010 Astronomy Lab Manual, Fall 2011 (this booklet), available from the CU Bookstore. Replacement copies are available in Acrobat PDF format downloadable from the SBO website: http://cosmos.colorado.edu/sbo/manuals/astr1010/astr1010.html ASTR 1010 Astronomy Lab 5 General Information5 • Calculator. All students should have access to a scientific calculator that can perform scientific notation, exponentials, and trig functions (sines, cosines, etc.). • A 3-ring binder to hold this lab manual, your lab notes, and lab write-ups. • Highly recommended: a planisphere, or rotating star map (available from Fiske Planetarium, the CU bookstore, other bookshops, and on line). THE LABORATORY SECTIONS Your laboratory session will meet for 1 hour and 50 minutes in the daytime once each week in the Sommers-Bausch Observatory (SBO), Classroom S175. Each lab section will be run by a lab instructor, who will also grade your lab exercises and assign you scores for the work you hand in. Your lab instructor will give you organizational details and information about grading at the first lab session. The lab exercises do not exactly follow the lectures or the textbook. We concentrate on how we know what we know; thus we spend more time making and interpreting observations. Modern astronomers, in practice, spend almost no time at the eyepiece of a telescope. They work with photographs, satellite data, computer images, or computer simulations. In our laboratory we will explore both the traditional and more modern techniques. You are expected to attend all lab sessions. The lab exercises can only be done using the equipment and facilities in the SBO classroom. Therefore, if you do not attend the daytime lab sessions, you cannot complete those experiments and cannot get credit. The observational exercises can only be done at night using the Observatory telescopes. If you do not attend the nighttime sessions, you cannot complete these either. NIGHTTIME OBSERVING You are expected to attend nighttime observing labs. These are held in the evenings approximately every second or third week at the Sommers-Bausch Observatory, Mondays through Thursdays. Your lab instructor will tell you the dates and times. Write the dates and times of the nighttime sessions on your calendar so you do not miss them. The telescopes are not in a heated area, so dress warmly for the night observing sessions! If you have a job that conflicts with the nighttime sessions, it is your responsibility to make arrangements with your instructor to attend at different times. 6 ASTR 1010 Astronomy Lab 6 General Information THE LABORATORY WRITE-UPS You are expected to turn in lab assignments of collegiate quality. This means that they must be neat and easy to read, well-organized, and demonstrating a mastery of the English language (grammar and spelling), as well as mastery of the subject matter. Your presentation of neat, well-organized, readable work will help you prepare for other courses and jobs where appearance certainly counts (and it makes your work much easier to grade!). By requiring you to explain your work clearly, we can ensure that you fully understand it. If you find writing clear explanations to be difficult, it could mean that you do not understand the concepts well. Your lab instructor can help you in this area; simply ask his or her assistance. Some of the labs are designed to be written up as full reports. A few are of the "fill in the blank" type. In either case, please use the following guidelines: 1. Write the title and date at the top of the first page of the exercise. 2. Write an introductory sentence or two describing what you are doing in that exercise. For instance: "Today we used the heliostat to observe and draw sunspots." 3. Number the parts of your lab the same as the numbers in the lab manual: I.1, I.2, II.1, II.2, etc. This is particularly useful to the instructor in finding your responses to the questions. 4. Put titles on your figures, and label the columns in your tables. 5. Put units after your numerical answers. An answer