Spot the North Star

Over the centuries, humans discovered that the North Star can function as a guiding point towards the directional north. Being able to find the North Star is a great survival skill, but spotting it can also be a fun activity on a clear night.

Steps

Finding the Big Dipper

1. Know what to look for. Ursa Major is a constellation that is also called "Big Bear," "the Big Dipper," or "Plough". The two outermost stars in the cup of the "dipper" (or the "blade" of the plough) are called the "pointers" because they describe a straight line that points to the North Star (see figure).
2. Find the constellation of Ursa Major. The Big Dipper is comprised of seven stars that are very recognizable in the night sky. The seven stars compose a shape that looks like a cup with a handle.
   • To make it easier to find Ursa Major, try using a constellation map if one is available. You can also download a constellation finding app on your devices (like SkyView for Apple devices or SkyMap for Androids).
   • Also try looking on a clear night. The absence of clouds will make it easier to spot the star groupings.
3. Understand that the Big Dipper changes positions in the sky. Ursa Major rotates in the sky, so its position depends on the time of your at which you are viewing it. It always rotates around the North Star. So, sometimes the cup is facing up, while other times the cup faces down or to the side.
   • Remember that the Big Dipper is a fixture of the Northern Hemisphere’s sky. So you will only be able to see it and follow these guidelines if you are in the Northern Hemisphere.
   • Here are some seasonal guidelines for finding the Big Dipper based on its location at midnight:
     • In the spring, the Big Dipper is located to the north of the North Star (Polaris) with the cup facing downward.
     • In the summer, the Big Dipper is located just west of Polaris with the cup facing to the right.
     • In the fall, the Big Dipper is situated to the south of Polaris with the cup facing upright.
     • In the winter, the Big Dipper can be found to the east of Polaris with the cup facing towards the left.

Finding the North Star

1. Know your latitude. Latitude is the position north or south of the equator. The height of the North Star above the horizon is equal to the latitude of the observer. It cannot be seen by an observer on or below the Equator although, as a practical matter, it will be too close to the horizon to be observed south of 10 degrees of North Latitude.
   • For reference, here are some latitudinal measurements of some major locations in the Northern Hemisphere:
     • The North Pole has a latitude of 90 degrees north.
     • Reykjavik, Iceland has a latitude of 70 degrees north.
     • Juneau, Alaska and Edinburgh, Scotland have a latitude of 60 degrees north.
     • Seattle, Washington, New York City, and Venice, Italy have a latitude of 50 degrees north.
     • Denver, Colorado and Seoul, South Korea have a latitude of 40 degrees north.
     • New Orleans, Louisiana and Orlando, Florida have a latitude of 30 degrees north.
     • Mexico City, Mexico and Kingston, Jamaica have a latitude of 20 degrees north.
     • San Jose, Costa Rica and Panama City, Panama have a latitude of 10 degrees north.
   • If you have access to the internet, you can use a latitude finder online to determine your latitude, like the one offered by NASA.
   • If you don’t know your latitude and you don’t have access to the internet, you can determine your latitude by looking at the sun at noon.
     • Put one flat board or stick in the ground pointing upwards so that it is perfectly perpendicular with the ground.
     • Use another flat board on the top (making a T with the two boards), but tilt the top board toward the sun. The angle of the shadow cast by the sun will be the degree of your latitude.
     • Note that these readings are only accurate on March 21st and September 21st (the spring and fall equinoxes). In the winter (specifically December 21st) you should subtract 23.45 degrees from your reading and in the summer (specifically June 21st) you should add 23.45 degrees. These variations in measurement exist because of the way the Earth is tilted when it orbits the sun.
   • If you know your location in terms of degrees of latitude, face north and look for a moderately bright star that many degrees above the horizon. A fist held out at arm's length represents approximately 10 degrees in the sky and can be used to measure the height above the horizon.
2. Spot the North Star in the night sky. The two outer most stars in the “cup” of the Big Dipper (the two farthest from the “handle”) are the keys to finding the North Star.
   • Draw an imaginary line straight through these two stars toward the Little Dipper. This will lead you to the handle of the Little Dipper. The brightest star at the end of the handle of the Little Dipper is the North Star.
   • The North Star (Polaris, or sometimes Dhruva Tara (fixed star), Taivaanneula (Heaven's Needle), or Lodestar) is a Second Magnitude multiple star about 430 light years from Earth. Because it is very close to the North Celestial Pole, it appears stationary over the Northern Horizon.
3. Find Cassiopeia. The constellation of Cassiopeia, which looks like a big "W," is always opposite Ursa Major. The North Star is located approximately midway between the central star of Cassiopeia and Ursa Major. This trick is especially helpful in the Fall when it is harder to see the Big Dipper.

Using the North Star as a Guide

1. Trust the North Star. The North Star is more reliable than a compass, which can be affected by environmental factors and periodic variations. If you can find north by locating the North Star and your compass tells you something different, follow the direction the North Star leads you.
2. Determine latitude from the North Star’s location in the sky. Where the North Star appears in the sky depends on your latitude. At the North Pole, the North Star appears directly overhead, but at the equator, it would appear on the horizon – both corresponding to the latitudes of the location.
   • If you use the “fist” method and count how many “fists” the North Star appears over the horizon, that will give you your latitude. Remember that a “fist” counts as approximately 10 degrees for latitude.
3. Figure out where you want to go. Use the North Star to guide you in a direction, or at the very least, to keep you from going in circles if you are lost. Think about where you are and which direction would be the most helpful, especially if you are lost in the wilderness and need to get back to civilization.
   • Once you have found the North Star, facing it will point you due north. If you face directly away from it, you’ll be facing due south.
   • When you are facing the North Star, stretch your arms out to your sides. Your left hand will be pointing due west and your right hand will be pointing due east.

Warnings

• As is falsely believed by many, the North Star is actually not the brightest star in the night sky.

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• Stargaze Comfortably

Sources and Citations

See also

• Select Astronomy Binoculars
• Make a Sun Chart
• Find the Hyades Star Cluster
• Become an Astronomer
• Tell Whether the Moon Is Waxing or Waning
• Find a Meteorite
• Find an Iridium Flare
• Draw the Solar System
• View an Eclipse
• Participate in SETI

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