I am working on trying to calculate what the parallax is with the following information. Latitude of the sun declination sin of declination angular separation, sun to star I have all of this data, I'm supposed to be able to calculate it from this info. Don't know how. Lost in the instructions. What needs to be divided, multiplied, sin'd or etc...? Determine the absolute value of the change in parallax angle when the baseline is changed by 6378 km by measuring the equivalent change in angular position for a change of Sin(declination) = 1.0. Express the change in angular separation in arc seconds. Please help!!