Parallax is
A)the apparent motion of an object due to the motion of the observer.
B)the distance between two foci of an ellipse.
C)the small circle that the planets slid along in Ptolemy's geocentric universe.
D)the circular orbits used in Copernicus' heliocentric universe.
E)half the length of the shortest diameter of an ellipse.

Question

Quizplus · Accepted Answer

Parallax is defined as the apparent motion of an object due to the motion of the observer. This can be observed when you hold your finger out in front of your face and alternately close each eye - your finger appears to shift position. This is due to the different perspective each eye has on the object. Parallax is also used in astronomy to determine the distance to stars.

Parallax Is