Question 1504Navigation General

The correct answer is B) is the full phase. The key to understanding this question is the statement that "Mars is only seen at two phases". This means that Mars can only be observed in two distinct configurations relative to the Earth and Sun. The full phase, where Mars appears fully illuminated from our perspective on Earth, is one of these two possible configurations. The other options are incorrect because: A) 0° elongation refers to when a planet appears to pass directly behind the Sun from our perspective, not a distinct phase of Mars. C) Conjunction is the term for when a planet passes between the Earth and Sun, not a phase of Mars. D) Sunrise and sunset are not phases of Mars, but rather the times of day when Mars may be visible in the sky.