Astronomy 110 Laboratory: Student Guide

Fall 2008 Astronomy 110L Mon. 7:00 — 10:00 pm


My motivation in developing this class came from my students. For years, Astronomy 110 students have said they wanted a chance to observe the night sky. This astronomy laboratory was developed to give students some practical knowledge of the stars and some `hands-on' observing experience. We assume that you are truly motivated and interested, and that you are willing to invest some time in learning the stars and the use of telescopes. These are not terribly difficult subjects, and anyone can learn something about them. Nonetheless, you will need commitment to do well in this class. Although we have asked you to buy a book, this subject can't be learned by reading a book or going to lectures. The point of this class is to see for yourself.

When studying astronomy in this way, some patience is necessary. For example, the weather may be bad when we go out to observe. Even when the weather is good, the things we are trying to see may be hard to find, indistinct, or just plain invisible; the best course of action may be to keep on looking, find something else to look at, wait until conditions improve, or try again another night. Finally, observing the universe makes new demands on your visual abilities; you must learn new ways to see, and that will take time.

I can help you in this process, but I can't work miracles. If you get frustrated, you have to motivate yourself to keep on looking — because if you don't look, you won't see anything! How you find motivation is your business. Your motivations are part of your personality, and I can't change your personality any more than I can tell you what foods to eat, what music to enjoy, or what kind of friends to make. (That's not my job, and I'm very happy that it's not!) If you understand that your motivation is your responsibility, I welcome you to this class and to the study of astronomy.


Working in pairs or groups is quite common in science labs, and this lab is no exception. Teamwork can be quite effective; it's often possible to figure things out faster if you work with another person, and some experiments are much easier with two pairs of hands. Many of the lab activities are designed for teams of two to four people.

In a real team, everybody is involved and contributes to the group effort. To insure that everybody is involved, we require you to use your own words in writing up your lab reports. This is very important — expressing yourself with your own words will help you to understand the material. It's pretty obvious when people copy from each other, and we will not give credit if people turn in identical work! On the other hand, we will give you credit if you use your own words — because that shows that you understand what you have been doing.


The point of this course is to see as much as we can. We will try to observe every night the weather seems reasonably good, and meet indoors only when bad weather rules out any kind of observation.

Unfortunately, the UH campus is not a good place for observations; there are too many lights, and Manoa is often cloudy. Therefore, we will be making field trips to observe. Most of our observing session will be in Kapiolani park. The park is a pretty good observing site, and it's easy to get there. We will also arrange several trips to darker sites where we can observe fainter stars.


Astronomy is a very safe activity. Unlike some science labs, we have little need for hazardous materials or equipment. We will be working outdoors at night, but we are a large group and there is safety in numbers. Still, people sometimes feel nervous being out at night; if you feel threatened, please let us know.

There is one safety rule which must be emphasized, even though it may not seem all that relevant to this class: NEVER LOOK AT THE SUN THROUGH ANY TELESCOPE OR BINOCULARS unless you are using a professionally-designed solar filter! It's important that the filter cover the entire aperture of the telescope or binoculars and that it is securely attached so it can't fall off by accident. The telescopes we use in this class can take all the sunlight falling on an eight-inch circle and concentrate it into a spot half an inch in diameter. That concentrated light is about 250 times brighter than normal sunlight; it can permanently destroy your vision in much less time than it takes you to blink your eye.

For legal reasons, you must sign a release form before the first field trip. This is the same legal language used on release forms for field trips in other classes at UH.


We will be observing outside at night for several hours at a time, and you should plan to dress appropriately. It can get a little cool in the evenings, and clothes which were comfortable in mid-afternoon will not keep you warm enough at night. Wear loose-fitting clothes you can move around in easily, and bring a sweater or jacket. We may have to wait out the occasional shower, so bring a poncho or umbrella.

Low blood sugar makes it harder to see faint stars; you may bring along a snack when we are observing.

Nicotine impairs your night vision, and you should avoid smoking before or during the class (or at any other time, if you want to live to see the next return of Halley's comet). If you must light up, wait until we take a break, and move well away from the telescopes and from anyone who might not like the smell of cigarette smoke.


We will provide all the key equipment for this class, including telescopes, binoculars, and other optical aids. Detailed instructions will be given in class; this is just a summary.

  1. 8-inch Dobsonian Reflecting Telescopes. These are robust and simple to operate, yet quite powerful when used properly. We have one scope for every four students in this lab.

  2. 10 × 50 Binoculars. Binoculars are useful for star-gazing; they help to bridge the gap between naked-eye and telescopic views. We have one pair of binoculars for every student.

  3. Observing Flashlights. Ordinary flashlights are too bright to use while observing, and white light temporarily impairs your ability to see faint stars. We will use special red LED flashlights when observing; we have one for every student.

  4. Refracting Telescope Kits. These simple kits will help you understand the operating principles of larger telescopes. We have one kit for every student.

  5. Spectroscope Kits. A spectroscope is a device which separates light by color (technically, by wave-length or by energy per photon). We have one kit for every student.

  6. Cross-staff. A cross-staff is a simple device for measuring angles — for example, the angle between two stars. We have one for every student.

You will need to buy a few things for this class. These are available at the UH bookstore or your local shopping center:

  1. A ring binder for handouts and other course material.
  2. A clip-board, useful in making drawings while observing.
  3. Pens, pencils (colors optional), pencil sharpener, eraser, etc.
  4. A ruler marked in centimeters. Should be at least 30 cm long.
  5. A calculator. Advanced math functions will not be necessary.
  6. A straw beach-mat or blanket — convenient when viewing constellations directly overhead.


Each week we will give you one or more handouts which you should read before next week's lab. These will be distributed during the lab meetings; you can also get them from the class web site. Because we can't predict the weather a week in advance, we will often provide two handouts: one for an observing project, and another for an indoor lab project. If we wind up observing, we will generally recycle the indoor project for the following week. If we have to work indoors, we may or may not be able to recycle the observing project; some observations can only be made at specific times.


Drawing astronomical objects is a good way to improve your observing skills. When you make a drawing you concentrate on what you are seeing; as a result, you will see things you might not have noticed, and remember more of what you have seen. Artistic ability can help, but the point is not to produce beautiful pictures, so don't worry if your sketches are not artistically satisfying. The main point is to make a serious effort to represent what you see on paper. If you try, you may be surprised at how much you can actually show in a drawing.

On each drawing you make, you should note the name of the object, the date and time, and the equipment you used. We will generally provide worksheets for your drawings with places to write these things down.


A second component of your work is writing up the observations and experiments you have performed. This allows you summarize your work and draw conclusions from your observations. Detailed instructions will be provided with the assignments, but in general we expect you to follow the traditional format for lab reports, which includes an introduction, a list of the equipment used, a description of your results, and a discussion of your conclusions.


Instead of a final exam, we will have a short quiz every week. The quiz may be given indoors at the start of class, or outdoors during an observing session; you should be ready for either one, since we won't know ahead of time if we will be observing or working inside. The quiz will test you on the reading assignment or on the activities of the previous weeks. You can probably do well on the quizzes without extra study, but it is important to do all the assigned reading, and a good idea to briefly review last week's work before coming to class.

Each indoor quiz will have one question requiring a short written answer. The quiz will start at 7:05 pm, and end by 7:15 pm. We will close the door when the quiz starts and ask anyone who comes late to wait outside until the quiz is over; this is to spare people taking the quiz the distraction of late arrivals. Makeup quizzes will only be given to those with a valid excuse for being late.

Outdoor quizzes will be given during observing sessions. They will test practical observing skills and familiarity with the night sky; for example, we may ask you to point to a constellation we studied the week before, or focus a telescope on a particular star.

Before setting your final grade, we will drop your two lowest quiz grades; thus you can miss two quizzes without directly affecting your final grade. This should not be taken as encouragement to skip any quizzes! If you decide to skip a quiz, you risk missing an opportunity to do well on what may turn out to be an easy question. To increase your chances of a good final grade, you should make a point of showing up in time for all quizzes!


Unlike some classes, this class is not graded on a curve. Curves predetermine the percentages of students getting As, Bs, Cs, and Ds; that seems unfair, and may discourage people from trying to do their best. You will get written comments and letter grades (including plus and minus grades, when appropriate) on your quizzes and on each report or drawing you turn in. We will provide as much feedback as possible so you will know how you are doing in this class.

Your final grade will depend on the reports, worksheets, and drawings you hand in, your quiz scores, and your attendance record. Work handed in counts for 70% of your grade, while quizzes count for the remaining 30%. If you've missed two or more labs, your final grade will be lowered by one-third of a letter for every two lab sessions you have missed without a valid excuse (for example, if your total grade was an "A-", but you missed two sessions, you would get a "B+"). Valid excuses include serious illness, family emergencies, and the like; we can make allowances for sports or cultural activities if you bring a note from your coach or instructor beforehand.


As a university student, you may be going through a time of rapid change. Perhaps you are living away from home for the first time. You have new freedoms — the freedom to decide your own hours, chose your associates, set your own priorities. With those freedoms come some new responsibilities.

Attendance is one of your responsibilities. We will take attendance each time the class meets. You can miss one lab without penalty; if you miss two or more without a valid excuse, your final grade will suffer, and you may fail the class.

Your responsibilities do not end when you come to class. I don't expect you to pay full attention every moment, but if your attention wanders then you must make an effort to focus again. I can't direct the focus of your mind — you are the only person who can do that. We will take a 15 minute break about half-way through each class; please limit social activities and discussions unrelated to astronomy to the break.

You are also responsible for handling the equipment with care. Telescopes and accessories are expensive, and we can't afford many replacements or repairs. Accidents can be forgiven, but carelessness is another matter; anyone who recklessly or deliberately damages equipment will automatically fail the course.

It is your responsibility to know and follow the rules for the labs, reports, and quizzes. These rules are designed to make sure that everyone gets full credit for their work. Someone who tries to gain credit without doing the work, or tries to prevent other people from getting credit for the work they have done, is cheating. Any action which gives someone an unfair advantage cheats everyone. Treat other students as you'd like them to treat you.

Joshua E. Barnes      (barnes at
Updated: 25 August 2008
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