If you have ever had a medical checkup, you have probably heard about the Body Mass Index (BMI) that it supposed to have an optimal value around 25. Probably you were told to take your weight in pounds, divide it by the square of your height in inches and multiply the result by 703 to find your BMI.
Well, astronomers think there are large number of stars and guess (estimate) that there are around 1 septillion stars in the Universe1. If you look at the night sky, you can see around 3,000 stars with the naked eye. A galaxy is a group of hundreds of billions of stars that are relatively close to each other.
About-face of Polaris steers you due south. Polaris is not the brightest star in the nighttime sky, as is commonly believed. Itâs only about 50th brightest. But you can find it easily, and, once you do, youâll see it shining in the northern sky every night, from N. Hemisphere locations.or example, a famous star called Thuban, in the constellation Draco the Dragon, was the North Star when the Egyptians built the pyramids. But our present Polaris is a good North Star because itâs the skyâs 50th brightest star. So itâs noticeable in the sky.