The Correct Answer and Explanation is:
The correct option is 2.
The term “circumpolar” describes specific constellations that never set below the horizon from an observer’s viewpoint at a particular latitude. These star patterns are situated close to one of Earth’s celestial poles. As the Earth rotates, these constellations appear to trace a full circle around the pole star, such as Polaris in the Northern Hemisphere, remaining visible throughout the entire night, every night of the year. Which constellations are circumpolar is entirely dependent on the observer’s latitude; the closer you are to the North or South Pole, the more constellations will appear circumpolar.
For an observer in the mid northern latitudes, for example in North America or Europe, the constellation in image 2 is a classic example of a circumpolar constellation. This image displays Cassiopeia, which is easily identified by its distinctive “W” or “M” shape. Its location in the sky is very near the North Celestial Pole. This proximity ensures that from these latitudes, Cassiopeia never disappears from view as it perpetually rotates around the North Star.
It is important to note that image 3, showing Ursa Major containing the Big Dipper, is also a circumpolar constellation for these same observers. Both are excellent examples. However, since the provided options are singular, selecting one correct example is necessary.
Conversely, the other constellations shown are seasonal and not circumpolar for most observers. Image 1 is Orion the Hunter, which lies on the celestial equator. It is a famous winter constellation that rises in the east and sets in the west, making it invisible for many months of the year. Image 4 shows Scorpius, a bright zodiacal constellation. It is located deep in the southern celestial hemisphere, meaning for northern observers it only skims above the southern horizon during summer evenings and is not circumpolar. Thus, image 2 is a correct answer.
