Using Stellarium to Probe the Night Sky
Part 1: Setting Your Location and Time in Stellarium
The purpose of the first few exercises is to help users set their location and time
information in Stellarium. Stellarium uses your latitude and longitude to accurately
display objects that can be seen in the night sky. Luckily, information for many major
cities has been included, including Champaign-Urbana.
Setting the Location and Time
1. Move the mouse to the bottom left of the screen. A toolbar will become visible.
Select the Location Window button.
2. Type “Urbana” into the search box at the top right of the Location Window.
Select “Urbana, United States” from the list.
3. Click on the “use as default” checkbox, and close the location window.
4. Again, move the mouse to the bottom left of the screen. A toolbar will become
visible. Select the Date/Time Window button (see below).
Location
Window
Button
5. The values for year, month, day, hour, minutes and seconds can be changed by
typing new values, by clicking the up and down arrows above and below the
values, or by using the mouse wheel. Set the date and time to September 4,
2015 at 8:00:00 PM. But be careful! Stellarium uses a 24-hour clock (e.g., 8:00
AM is 8:00, 8:00 PM is 20:00).
6. Why is it important to set Stellarium to your specific
a. location?
b. date?
c. time?
Part 2: Naming Objects
Humans have observed the stars for millennia. The ancients named the bright stars, as
well as large groups of stars – also known as constellations – after mythological beasts,
gods, demigods, and ordinary household objects. Astronomers continue to use the
names of the constellations first recorded by ancient astronomers thousands of years
ago. It is here that we may begin to learn about where objects are located in the sky and
how they are named.
Astronomers officially recognize 88 constellations today. From the mid-northern
latitudes, you can see over half of them. Most are visible every night from your location
at some time during the night. Stellarium helps you to find them, so you can go outside
on any clear night throughout the year and look for them yourself.
Find the Constellation Cassiopeia
1. Be sure your location and time are set to Urbana at 8 PM on September 4, 2015.
2. Show the constellation names by clicking the Constellation Labels button
on
the main toolbar.
3. Optional: Press the ‘B’ key to turn on the constellation boundaries. These will
appear as dashed lines.
4. Find the constellation Cassiopeia. You may need to look around; use the mouse
or cursor keys to explore the sky.
5. Look at the bright stars in Cassiopeia. Can you make a picture in your mind by
“connecting the dots”? If so, what image do you see in the stars?
6. Go to the main toolbar and click on the Constellations button
. A stick figure
of the picture the constellation is supposed to represent will appear. Using the
stick figure as a guide, what image do you see now?
7. Finally, go to the main toolbar and click on the Constellation Art button . The
classical image of the constellation will appear. Historically, what is Cassiopeia
supposed to represent?
Find two more constellations on September 4
1. Turn off the constellation lines and art.
2. Make sure the date and time is set to 8 PM (20:00) on September 4, 2014.
3. Find a constellation visible in the evening on this day(other than Cassiopeia).
Which did you choose?
4. Display the Constellation art. What does the constellation you chose represent?
5. Go back to step 1 and repeat each step for a constellation other than Cassiopeia
and the one you already chose.
Find the Bright Star Antares
1. Make sure your date and time are still set to September 4th, 2014 at 8pm!!
2. Click on the Search window button
on the side toolbar.
3. Enter “Antares” into the Search Dialog and click the “find” button. Stellarium will
point you at that object in the sky.
4. In which constellation is Antares located?
5. What is the color of the star? Compare it to the nearby and very bright star
Arcturus.
6. When Antares is selected, there should be a box of information in the upper left
corner of the Stellarium window. What is the distance to Antares in light-years?
Find the Planets
1. Click on the Sky and Viewing Options window button
on the side toolbar.
2. In the Labels and Markers/Sky section, slide the Planets bar all the way to the
right. This will ensure all Solar System bodies are labeled (including planets,
dwarf planets, and asteroids).
3. The Sun sets this evening around 7:45 PM (19:45). Set your date and time to a
little bit after this, so around 8:15 PM (20:15).
4. Scan all around the sky. What planets are visible in the sky at this time, and in
which constellations are they located (it will help to turn on the constellation
lines – press C or click
)?
5. Now set your time to later in the night, at 11:30 PM (23:30). What planets are
visible at this time tonight, and in which constellations are they located?
6. Press the ‘ , ’ button. This turns on the ecliptic, which will appear as a red line
running across the sky. Remember, this is the path the Sun takes across the sky
over the course of the year.
7. Where are the planets visible tonight located with respect to the ecliptic? Look
at different times throughout the night so you can see more than one.
Find the North Star, Polaris
1. Set your date and time to September 4th, 2015 at 8:00 PM (20:00).
2.
3.
4.
5.
6.
Click on the Search window button
on the side toolbar.
Enter “Polaris” into the Search Dialog and click the “find” button.
In what cardinal direction is Polaris?
In which constellation is Polaris located?
Turn on the constellation art. What is the classical representation of this
constellation?
7. Go to the main toolbar and click the Time Rate Increase button
and watch the motion. Describe what you observe.
a few times
Polaris’ Position Around the World
As the North Star, Polaris can be used as an indicator of an observer’s position in Earth’s
northern hemisphere. We already saw that Polaris points almost directly north, making
it a useful compass. Now we will see another way that Polaris can be used to help
indicate our position on Earth.
In this exercise, you will record several cities’ latitudes and longitudes and the altitude
of Polaris at that location. Fill out the table below.
City
Latitude of city
Longitude of city
Altitude of Polaris in
degrees
Champaign, IL
Stockholm, Sweden
Honolulu, Hawaii
Juneau, Alaska
Beijing, China
Now that you have retrieved some information about cities in the northern hemisphere,
briefly discuss how Polaris can help you figure out your position on Earth. How is this
useful? In what ways is it not useful?
Identify Circumpolar Constellations
1. Set your location and time back to September 4th, 2015 at 8:00 PM (20:00) in
Urbana.
2. Use the cursor keys or the mouse to pan around until you are facing north.
3. Go to the main toolbar and click on the Constellations button
button
and the Names
if they aren't displayed already.
4. Go to the main toolbar and click the Time Rate Increase button
a few times
and watch the daily motion.
5. List the constellations that do not go below the northern horizon.
These circumpolar constellations are visible every night throughout the year.