Name_________________________

STUDENT INSTRUCTION AND ANSWER SHEET

Activity 4: The Sun is a Star?

A. Obtain a set of Star Cards from your teacher. Examine each star card and using the information provided, sort the stars by their distance from Earth, from largest to smallest.

B. Does the star's temperature appear to depend on the distance from the Earth?

C. Compare the color of the star to its temperature. Compare the spectral class of the star to its temperature. Do the color or spectral class of the star appear to be related to the star's temperature?

D. Sort your star cards by temperature, from coolest to hottest.

E. Consider the four characteristics (1) temperature, (2) color, (3) distance, and (4) class or spectral type. Which characteristics most strongly influence the size and location of the habitable zone? Explain your reasoning for each.

F. If we are looking for Earth-like life elsewhere in the universe, which of the stars described on the Star Cards would you explore first? What spectral classes did you choose? Explain the reasoning behind your choices.

Scientists believe that life as we know it is most likely to exist around stars most like our Sun, in the F, G and K classes. Size, temperature and light appear to be important factors in identifying these stars.

G. How would the zone of habitability be different around an "F" star, or a "K" star as compared to the Sun? Explain your reasoning.