✰​ Launch “Star in a Box”, set it to “advanced” and open the lid. The main plot is a Hertzsprung­-Russell diagram. On the right, the information panel allows comparisons between the radius, surface temperature, luminosity and mass of the star (relative to the Sun). The starting parameters are for our Sun. 
A.​ ​Set speed to “normal”, then click the play button below the Hertzsprung-­Russell diagram to show the Sun’s evolution. Once it is complete, you can click on “Data Table” (upper right) to see the final values for each stage in the life cycle. 

1. During its first 8000MY the sun’s in the ____________ stage. After a brief transition stage called “HR Gap”, it enters the __________________ stage.
2. Now click on the light bulb to open the luminosity scale. Reset and run again. In what stage will the Sun be at its brightest? ________________.
3. Click on the thermometer. Reset & run. In what stage will the Sun be at its hottest? _____________
4. Watch the timer & run again. In which stage does the Sun spend the longest time? _____________
5. Click on “star size”. In which stage of life do you think the Sun undergoes the most change? ______
6. What kind of star will the Sun be at the end of its life? ____________
7. How long will the Sun live for? ________________  How long is that in billion years? __________
B. ​Now, in “Star Properties” you can explore the evolution of different mass stars. 

1. Choose stars of lesser masses and compare their position on the H-R diagram main sequence to our sun’s position. Where do they lie on the main sequence? _______________________________

2. Choose stars of greater masses and compare their position on the H-R diagram main sequence to our sun’s position. Where do they lie on the main sequence? _______________________________ ________________________________________________________________________________
 
3. What are the names of the final stages of these star’s lives? 0.2⊙︎ __________________________ 4⊙︎ ________________________ 20⊙︎ ________________________

4. Which of the star masses above (Q#3) lived the shortest life? ________The longest life? ________