PHYS0270 Laboratory 1
Constellations
An Iridium F lare in the c onstellation O rion Taken from the B &H rooftop o bservatory 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 to identify some constellations. Then, using your star
wheel planisphere and “star hopping”, 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 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: Deneb, Vega, Altair, Albireo, Dubhe, Merak
and Polaris.
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 Cygnus 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.