Once you're facing toward Polaris, you know you're facing north, which can help you orient yourself any evening you're out stargazing. The Southern Hemisphere doesn't have a bright star that marks the south celestial pole. Observers there can use other clever ways to find due south, including using the stars of the Southern Cross constellation to point the way. One other note about the North Star is that it's a title that passes to different stars over time.
Earth's axis of rotation wobbles over the course of about 26, years, the way a spinning top also wobbles as it spins. This causes the celestial pole to wander in a slow circle over the eons, sweeping past different stars. The first is rather easy, the second is maybe challenging. The answers are given in the second and fourth photos. If you're a person whose known this simple trick for years, then I hope this instructable will inspire you to share your knowledge with others. If you're a person whose never looked at the stars before, then I hope this piques your interest in the night sky.
And if you're a person who is inexplicably lost in the wilderness but somehow has a wi-fi connection and decided to check instructables. Happy star gazing! Question 3 years ago on Step 4. I've looked at the stars for many years. My uncle showed me the big and little dipper when i was a 7 yr.
Old starried eyed boy. But i never figured how to find the north star. Thank you. Just want to thank you for this great article. Very helpful. Will be locating the Northern Star tonight. That's because half of the night only the "bowl" of the Big Dipper part of the constellation Ursa Major will be visible to most observers in the Northern Hemisphere. The constellation "Cassiopeia" looks like a broken 3 when rising, a broken M when overhead, and a backward 3 when setting.
When the Big Dipper is too low to find reliably, Cassiopeia is usually findable. There is a bonus to finding Cassiopeia, too. In the photo below, Cassiopeia is in the upper left and all you see of the Big Dipper lower right are two of the stars. Follow the stars of the Big Dipper from the handle to the side of the bowl, to the bowl bottom, and up the other side; the two stars forming the second side, Dubhe and Merak, point to Polaris. Take the distance between Dubhe and Merak; Polaris is the bright star that sits about five times that distance away.
Polaris actually is part of a binary two star system. Of the stars nearest to our Sun, about half are known to be in multiple systems two or more stars. These systems reveal a great deal of information. Because of their interactions, astronomers can determine the gravitational pull exerted by the companions and calculate the mass of the individual stars. Polaris is helpful to astronomers in another way; it is a variable star.
At the equator, Polaris would appear to sit right on the horizon. So if you travel to the north, the North Star climbs progressively higher the farther north you go. When you head south, the star drops lower and ultimately disappears once you cross the equator and head into the Southern Hemisphere. And always keep this fact in mind: Polaris is more accurate than any compass.
A compass is subject to periodic variations and can only show you the direction of the lines of the strongest magnetic force for a particular spot and for a particular time. But even Polaris isn't positioned exactly due north. Only about 0. In case you're wondering, 0. Aside from the North Star the two stars at the front of the Little Dipper's bowl are the only ones readily seen.
These two are often referred to as the "Guardians of the Pole" because they appear to march around Polaris like sentries; the nearest conspicuously bright stars to the celestial pole except for Polaris itself.
Columbus mentioned these stars in the log of his famous journey across the ocean and many other navigators have found them useful in measuring the hour of the night and their place upon the sea by their position relative to Polaris.
The brightest Guardian is Kochab, a second magnitude star with an orange hue. There is a famous Shakespeare quote that has Julius Caesar stating, "I am constant as the northern star. Like a spinning top that wobbles due to a force called torque, our spinning earth is also subject to torque that is caused by the gravitational forces of the sun and moon.
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