1) Using the distance from the Sun to the Earth in meters, calculate its brightness on the Earth in W/m^2. Use the formula Brightness= Luminosity/(Area of the Sphere)
2) Using the same method as in step 1, calculate the brightness of the Sun in Mercury.
3) Using the formula for the magnitude difference − = . (), what is the

difference of magnitudes of the Sun between the Earth and Mercury? (use the log function of your calculator).
4) Does the sun have a higher or lower apparent magnitude on the Earth than in Mercury? Explain your answer.