Draw a diagram showing the view from far above Earth's north pole. Show the Earth, moon and the sun's direction as they would be for this phase. Label the respective deferents and epicycles. If the geocentric model were correct, draw a picture predicting the appearance of Venus that would be seen if it is viewed through a telescope. Draw a diagram showing the orientation of Earth, Mars and the sun as they must be to match the observed configuration if the heliocentric model of the solar system were correct.
Astronomers use triangulation to determine distances within the solar system.
The application of triangulation is usually done by measuring parallax. Draw a diagram showing the parallax angle of some solar system object, and explain how that parallax angle yields a distance by triangulation. Suppose the method of parallax has been used to find the distance to the moon. Use the known distance to the moon to predict the parallactic angle that we would have measured. Astronomers have recently detected planets orbiting stars other than the sun.