Questions: Working with the Sun
1. At the beginning of the simulation, locate our Sun; is it on the Main Sequence? If
yes, look at the symbols above the ‘Play’ button and click on those; what are it’s
temperature (x-axis), brightness (y-axis), stage, and mass? Make sure you use the
correct units, for example, temperature is measured in degrees Kelvin (ºK).
2. How long does it take our Sun to just barely move off the Main Sequence (for
example, 5000 million years is 5 billion years, 10,000 would be 10 billion years)? At this point, what are the measurements of temperature, brightness, stage, and mass?
3. Stop the simulation or click on the dotted line at the highest temperature (farthest left of the path)–what is the temperature here? Why?
4. At the end of the life cycle path, what how old is the Sun and what are its
measurements (as listed in previous questions)?
Questions: Working with a star twice our Sun’s mass
5. On the lower left of the simulation is the option to set the mass to 2 times our Sun’s; do that by choosing 2X. Is it still on the Main Sequence? If so, what are it’s
temperature (x-axis), brightness (y-axis), stage, and mass?
6. How long does it take Sirius to just barely move off the Main Sequence (for example,5000 million years is 5 billion years, 10,000 would be 10 billion years)? At this point, what are the measurements of temperature, brightness, stage, and mass?
7. Stop the simulation or click on the dotted line at the highest temperature (farthest left of the path)–what is the temperature here? Why?
8. At the end of the life cycle path, what how old is Sirius and what are its
measurements (as listed in previous questions)?
A. Using 1 Earth-sized planet and 1 Sun-sized star, make sure you have the
options “Path”, “Velocity”, and “Gravity Force” clicked.
Answer the questions below.
1. Click the Play button .
What does the orbit shape look like? How long did it take the planet to orbit the star?
2. On the options, click Gravity to turn it off (not Gravity Force, the Gravity option above that)–what happened? Why?
B. Reset the simulation. This time, make the star twice as massive as our Earth
and run the simulation again.
3. What does the orbit shape look like? How long did it take the planet to orbit the star?
C. Reset the simulation, with the star size back to 1 and the planet size to Earth-
sized. This time, choose the upper right option that adds a moon to the planet.
Run the simulation.
5. What does the moon’s orbit shape look like? How long did it take the planet to orbit
the star this time? Is this different than in the first time we ran the simulation in part A?
6. Change the planet’s mass to 2 and run the simulation—what happened to the moon?
