Sky angles ranging from 5 to 25 degrees in extent can be determined using the stars of the Big Dipper. A yardstickįinally, another valued and fascinating use of the Big Dipper is that we can use it as a convenient astronomical yardstick by which we can measure angular sizes and distances (opens in new tab) in the sky. And now, during the winter we find it ascending the sky once again, standing on its handle around 9 p.m. This position in the sky is appropriate in a way, as bears are going into hibernation at this time of year, and as we mentioned earlier, the Big Dipper is part of the big bear constellation, which is now partially hidden below the northern horizon. But by summer it has turned counterclockwise by 90 degrees the bowl now points downward and it lies to the west of the pole during the early evening hours.īy fall evenings, the Big Dipper is far beneath Polaris and skims the northern horizon. From the relative position of the Big Dipper with respect to Polaris, the season of the year - and eventually with practice, even the month - can be determined by looking at the sky.ĭuring the hours just after darkness falls in the spring, we can find the asterism soaring high above the northern horizon and stretching to the point almost directly overhead (the zenith). In addition to its role as a sort of cosmic chronometer, the Big Dipper can also serve as a calendar. The Big Dipper twinkles over the snow-covered Alborz mountain range in Iran.
I know some people who are able to tell what time it is using this methodology within just a few minutes of what the actual time happens to be! If you go out several nights a week, and note afterwards what the time is when you go back inside, after a while you won't need to check the clock or your watch - you'll pretty much know what hour of the night it is. With practice, this can be carried to a surprising degree of accuracy. Through a process of mental association between the celestial and mechanical hour hands, it becomes possible to estimate the time directly from the sky alone. The length of time required to do these observations depends on how assiduous an observer you are.
#NICE CLOCK WITH SKY AND STARS HOW TO#
What is required to learn how to tell the time using the Big Dipper, is a period of frequent comparison - repeated anew for each season - of the position of the line running from Polaris through the pointer stars with the local time on your clock. The only thing that makes our sky clock different from the ones we have in our home (or around your wrist) is that the Big Dipper moves around Earth's geographic North Pole in a counterclockwise direction. Making out the Big Bear (Ursa Major) could prove a little more challenging.
Look high in the sky toward the northeast this time of year and you can't miss the Big Dipper.
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