Question

Mr. Greene's friend, Mary, lives in Sao Paulo, Brazil (latitude 23 degrees South). What will be the altitude to Polaris above the horizon line with respect to Mary?

Answer 1

Polaris, also known as the North Star, is not visible from Sao Paulo, Brazil, since it is in the Southern Hemisphere and Polaris only appears above the horizon in the Northern Hemisphere.

Step-by-step explanation:

The altitude of Polaris or the North Star directly corresponds to the observer's latitude if the observer is in the Northern Hemisphere. However, for Mary, who lives in Sao Paulo, Brazil at a latitude of 23 degrees South, Polaris would not be visible. This is because Polaris is located nearly directly above the North Pole and is only visible from the Northern Hemisphere. As one travels southwards from the equator, the altitude of celestial objects like the North Celestial Pole decreases accordingly until they are no longer visible. In Mary's case, this means Polaris is below the horizon and thus at an altitude of 0 degrees from her observation point.