Question 1512Navigation General

The correct answer is A) at conjunction. At conjunction, the positions of the Earth, Mars, and the Sun align such that Mars is on the opposite side of the Sun from the Earth. In this configuration, Mars is not visible from Earth because the Sun's brightness obscures Mars from our view. The other answer choices are incorrect because: B) at opposition, Mars is on the opposite side of the Earth from the Sun, making it clearly visible. C) from quadrature to opposition, Mars is visible, just not at its maximum brightness. D) at elongation angles near 180°, Mars is still visible, just not at its maximum brightness.