Big Dipper points to a most important star

  • By Mike Lynch Special to The Herald
  • Friday, April 25, 2008 1:25pm
  • LifeGo-See-Do

Last week in Starwatch we did a big celestial bear hunt for the constellation Ursa Major. That’s the formal Latin moniker for the Big Bear.

The Big Dipper that we know and love in the northern sky is not actually a stand-alone constellation, but does possess the brightest stars that make up the derriere and tail of the Big Bear. This time of year the Big Bear is flying upside down, high in the northern sky, and with not much eye strain it is easy to see, even in moderately light-polluted skies.

This week, it’s Ursa Minor’s turn, a constellation with a dual identity. Not only is it known as the Little Bear, it’s also the Little Dipper, and without a doubt that’s actually more what it looks like.

ADVERTISEMENT
0 seconds of 0 secondsVolume 0%
Press shift question mark to access a list of keyboard shortcuts
00:00
00:00
00:00
 

The problem is that it’s not nearly as bright as the nearby Big Dipper. The sad fact is that in a lot of city — and even suburban skies — it’s difficult to see completely. The good news is that you can use the Big Dipper to find and see as much as you can of the Little Dipper.

All you have to do is use the stars Merak and Dubhe, which make up the side of the Big Dipper’s pot opposite its handle, as “pointer stars” to Polaris, the brightest star of the Little Dipper. As you see on the diagram, draw a line from Merak to Dubhe and continue that line nearly straight down. Extend your clenched fist at arm’s length, and three of your fist widths should get you from Dubhe to Polaris. Polaris resides at the end of the Little Dipper, which is more or less hanging right side up.

Once you find Polaris, look for the next two brightest stars you can see to the right of Polaris. They’re Kochab and Pherkad, on the far side of the pot section of the Little Dipper. The really neat trick is trying to find the other two much dimmer pot stars to the left of Kochab and Pherkad, and the two equally dim handle stars to the right of Polaris. That may require a trip out into the darker countryside to enjoy.

Even though Ursa Minor is not exactly a marquee constellation, it contains a very important star. That star is Polaris, also known as the North Star. It’s certainly not the brightest star in the sky, but at my star parties, I like to refer to it as the “Lynchpin” of the heavens, because all celestial objects in the sky — the stars and even the sun and moon — circle around the stationary North Star every 24 hours as the Earth spins on its axis. (If you want a plain linchpin, throw your own party.)

It happens that Polaris shines directly above the Earth’s terrestrial axis. As we ride around the spinning Earth it appears to us that all of the stars make one complete counter-clockwise circle around the North Star in that 24-hour period. At our latitude of 47 degrees north in Everett, Polaris shines in the northern sky about 47 degrees above the northern horizon.

Stars and constellations close to the North Star make their circuit around Polaris completely above the horizon. They are known as circumpolar constellations. The rest of the stars and constellations farther away from the North Star have only part of their circular path above the horizon. The northern part of their circuit takes these stars below our northern horizon. The result for us is that these stars appear to rise above the eastern horizon and set in the west, much like our sun and moon.

Astronomically, Polaris is considered a supergiant star about 432 light-years distant, or just over 2,500 trillion miles away. It’s about 30 times the width of the sun and kicks out more than 2,200 times the light of our wimpy little home star. Like a lot of stars that appear as solo acts in the sky, Polaris is actually the brightest star of a three-star system.

Don’t count on Polaris to be our North Star forever, though. That’s because the Earth’s axis very slowly wobbles over a 26,000-year period. Thousands of years from now, Polaris won’t be shining above the Earth’s North Pole, but for now it’s the Lynchpin of the night sky.

Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis and author of the book, “Washington Starwatch,” available at bookstores and at his Web site, www.lynchandthestars.com

The Everett Astronomical Society welcomes new members and puts on public star parties. The Web site is members.tripod.com/everett_astronomy.

Talk to us

> Give us your news tips.

> Send us a letter to the editor.

> More Herald contact information.

More in Life

Auston James / Village Theatre
“Jersey Boys” plays at Village Theatre in Everett through May 25.
A&E Calendar for May 15

Send calendar submissions for print and online to features@heraldnet.com. To ensure your… Continue reading

Kyle Parker paddles his canoe along the Snohomish River next to Langus Riverfront Park on Thursday, May 8, 2025 in Everett, Washington. (Olivia Vanni / The Herald)
Tip to Tip: Kyle Parker begins his canoe journey across the country

The 24-year-old canoe fanatic started in Neah Bay and is making his way up the Skykomish River.

Photo courtesy of Historic Everett Theatre
The Elvis Challenge takes place Saturday at the Historic Everett Theatre.
A&E Calendar for May 8

Send calendar submissions to features@heraldnet.com. To ensure your item is seen by… Continue reading

Photo provided by Subaru U.S. Media Center
Subaru Adds Bronze And Onyx Trims to 2025 Ascent

Three-Row Family SUV Delivers Equal Parts Safety And Comfort

The 2025 Hyundai Santa Fe Hybrid SUV (Provided by Hyundai).
2025 Hyundai Santa Fe Hybrid evokes outdoor adventure

Boxy styling leaves lots of room for gear. A refined ride ensures comfort around town.

The 2025 Toyota Sienna minivan in the top-level Platinum grade (Provided by Toyota).
2025 Toyota Sienna maintains reputation for fuel efficiency

Every model in the minivan’s lineup has a hybrid powertrain.

An autumn-themed display at Wagner Jewelers in Marysville. (Olivia Vanni / The Herald)
Shine bright with Snohomish County’s top jewelry finds

Three dazzling shops where elegance, craft, and sparkle come together.

The 2025 Lexus TX 350 is a three-row luxury SUV. It’s offered in Base, Premium, Luxury, and F Sport Handling grades (Provided by Lexus).
2025 Lexus TX 350 welcomes new F Sport Handling model

Unique exterior highlights, a glass roof and sport-tuned suspension are among the attractions.

Hybrid Touring Photo Provided by Subaru U.S. Media Center
2025 Subaru Forester Hybrid Increases Fuel Economy And Range

Sixth-Generation Model Receives Complete Refresh

Image from Pexels.com
Top 3 Cannabis Shops You’ll Love in Snohomish County

Looking for quality products and good energy? Let’s discover the top spots.

Image from Canva.com
Chic & unique: The top 3 boutiques in Snohomish County you need to visit

From trendy finds to timeless pieces, discover the hidden gems that are redefining local fashion.

Image from Canva.com
Find your next favorite read in Snohomish County

Explore three of the finest bookshops where stories and community come together

Support local journalism

If you value local news, make a gift now to support the trusted journalism you get in The Daily Herald. Donations processed in this system are not tax deductible.