The position of Polaris in the sky varies with the latitude of an observer. For example, Houston, Texas, at thirty degrees latitude, is 30 degrees above the northern horizon and Polaris is located at ninety degrees latitude, so it appears directly overhead in Houston. The same pattern applies to other cities, such as the equator. But for the purposes of this article, let’s look at Houston in a practical sense.
It is interesting to note that the mass of Polaris is less than what is predicted by conventional Cepheid models. Previously, models predicted the star to be seven solar masses. However, new observations indicate that Polaris Aa may have lost mass over time, making it much older than expected. And it is possible that the star’s evolution was complicated by a merger in the past. This is the most likely explanation. Until recently, astronomers had a hard time confirming this hypothesis, but now we have a better idea.
Throughout history, Polaris has served as the North Star. In the Old Kingdom, the star was symbolically represented by a female hippopotamus. In the early third century B.C., the star was closest to the north celestial pole. The distance between Polaris and the celestial pole is approximately 27’09” and 0.4525 degrees. This distance is less than half the angular diameter of the moon when it is at its furthest from Earth.
The brightness of Polaris is about two thousand times fainter than Sirius, but that doesn’t mean it isn’t bright enough to attract attention. The fact that it doesn’t rise or set is another factor that contributes to its status as the North Star. But it is still worth noting that Polaris is only the 50th brightest star in the sky, so it is a stepping stone to other more interesting objects.
The new distance to Polaris has solved a long-standing mystery. Earlier astronomers had estimated its distance to be between 326 and 522 light years. However, the new distance fixes the intrinsic luminosity of Polaris and allows for more precise calibration of the star’s period-luminosity relationship. It is also 4.6 times brighter today than it was when Ptolemy first observed it. These observations provide a basis for determining whether Polaris is brighter than we originally thought.
Although not the brightest star in the sky, the North Star is easy to identify even in cities. It’s in the direction of true north, which differs from magnetic north. That’s why Polaris is also called the North Star, because it is almost directly overhead the North Celestial Pole. It is also the North Star, and the stars of the night sky appear to revolve around it throughout the year. Therefore, it is easy to see how a constellation like the Little Dipper can help us locate the North Star in the night sky.
The brightness of Polaris varies from magnitude 1.86 to 2.13. Before 1963, Polaris was more than 0.1 magnitude. After that, it gradually declined until 1966, where it suddenly decreased to just 0.05 magnitude. Since then, its brightness has fluctuated unpredictably and remains close to the 1966 magnitude. A paper from 2008 states that the brightness of Polaris may be increasing. But the brightness changes of the star are also important distance indicators.
If you’re planning a trip, the North Star is a reliable way to guide yourself. The North Star is the only astronomical object that maintains the same apparent position throughout the year. Finding Polaris in the sky will tell you where you’re heading in four different directions immediately. You can also measure the angle of the North Star to the horizon to get an additional data point on location. You’ll also find the constellation Ursa Minor and the Little Dipper.
The constellation Polaris lies in the constellation Ursa Minor. This constellation contains the group of stars known as the “Little Dipper”. The North Star is found in the last handle of the Little Dipper. You can also find Polaris in the constellation of Ursa Major, which contains seven stars. The stars of the Big Dipper point towards the North Star. When you’re looking at the constellation Polaris, remember to keep an eye out for these stars.
Another way to find Polaris in the sky is to use the Big Dipper. It has two stars on each end of the “cup” that point to Polaris. The Little Dipper, on the other hand, has a star called Polaris at the end of its handle. In either case, facing Polaris means that you’re looking at the north. However, the star is very faint in the Southern Hemisphere. If you’re in the Southern Hemisphere, it is impossible to see Polaris because of local light pollution.