PHYS0220 Laboratory 1 – Constellations
The purpose of this laboratory is to acquaint you with the night sky: to learn how to find various objects,
identify some constellations and bright stars by using the planisphere and celestial charts, to understand
how the night sky changes with time.
Lab Goals:
1. Learn how to find objects in the night sky using your star wheel (planisphere) and other star
charts.
2. Identify key constellations, stars and planets.
3. Learn astronomical measurement system of degrees, minutes and seconds.
4. Learn how to estimate the brightness (magnitude) of astronomical objects.
Procedure:
The TAs will initially help you identify some constellations. Then, using your star wheel and “starhopping”, use those constellations as aids to finding other constellations and stars.
Observations and Questions for this lab session:
1) In your lab notebook, indicate the location, time, date, weather conditions (approximate
temperature, % cloudiness, clearness of the sky) and the phase of the moon, if it is visible.
2) With the help of a TA, and then on your own or with a friend, identify at least five constellations
and the following stars: Regulus, Sirius, Castor and Pollux, Procyon, Betelgeuse and Rigel. In
your lab notebook, make sketches of these constellations with their relative height from the
horizon. Indicate the direction you are looking and include any landmarks (trees, buildings) that
may be present.
3) Name three constellations always visible from Providence.
4) People often look up in the sky and say there must be millions or billions of stars visible to the
naked eye. Figure out a simple method by which to estimate the number of stars visible at one
time. Describe your own method, apply it to the real sky, and come up with an estimate of your
own.
5) Describe the difference between a constellation and an asterism. Give an example of each.
6) Pick a constellation and find it on both the star wheel (planisphere) and in a more detailed star
atlas available from the TA. What is the magnitude of the faintest star visible in the
constellation?
7) What time did Orion rise today? What time did it cross the meridian? When will it set? Use the
planisphere to answer these questions.
8) Which stars are near the zenith right now?
9) Identify and indicate the location of any planets that are visible to the naked eye.
10) If visible at the time of your observations, what constellation is the moon in? Record the phase
of the moon.