Therefore, we can approximate the unit vector Q, which runs from Rochester towards the asteroid as the unit vector running from the center of the Earth towards the asteroid. Remember, Rochester define...Therefore, we can approximate the unit vector Q, which runs from Rochester towards the asteroid as the unit vector running from the center of the Earth towards the asteroid. Remember, Rochester defines the x-axis of our coordinate system, and the Hour Angle is exactly the projection onto the x-y plane of the angle between Q and the x-axis. Now that we know the effective baseline B and the parallax angle theta, we can use calculate the distance to the asteroid easily.
