3. Divide the actual diameter of the Sun in km (1.4 million km) by the diameter in pixels to get the image scale. This is similar to nding a scale on a map. 4. Choose one of the active regions near the Sun's equator. Make sure that it is recognizable in both images. .9. Use these images to nd the distance, X and Y (in pixels) that this feature moved between the two images. b. Try to click in the center of the active region, I know, I know, they move and change shape. Keep the Y values as close to each other as possible. c. Write down the X values. Subtract the small one from the big one. This is the distance in pixels that the active feature moved in pixels. 5. Multiply by the image scale from step 3 to nd the actual distance (D) moved by the active region in KM. 6. Since the spots are always moving at the same velocity, the period of the rotation of the Sun can be found using a ratio. A point on the surface of the Sun near the equator rotates all the way around the circumference of the Sun, 2*n"R, over the course of one orbital period. The images you are using were taken one day apart. The ratio of the times must equal the ratio of the distances as follows: Pi day " mo- 7. Calculate the period, P, of the Sun in days. (D is the actual distance in KM calculated above.) 8. Estimate the uncertainty of your measurements (in pixels). a. For example. do you think your measurement was accurate to one pixel? two pixels? eight pixels? This is your uncertainty. b. Use the following formula to estimate your fractional error: fractional error=(uncertainty)lx where x is the distance moved by the sunspot (in pixels). c. To nd the corresponding error in days. multiply by the period. Report the period as the number you calculated +i- your error. For example: 28+i-3 days. Questions for Part 1: 1. 2. 91:5.\" What is your image scaie (in km/pixei)? Sources of error in that value? What is the distance, x, the feature moved between the two images. Sources of error in this measurement? What is the actual distance moved (convert to km). Any introduced error here? What is the period, P, of the Sun in days? What is your fractionai error? Describe the 3 largest sources of that error