{"id":23180,"date":"2021-08-24T08:10:10","date_gmt":"2021-08-24T08:10:10","guid":{"rendered":"https:\/\/www.skyatnightmagazine.com\/?p=99392"},"modified":"2021-08-24T08:34:07","modified_gmt":"2021-08-24T08:34:07","slug":"how-to-find-the-north-star","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/rss_feed\/how-to-find-the-north-star\/","title":{"rendered":"How to find the North Star"},"content":{"rendered":"

<\/p>

By Scott Levine\n \t\t<\/p>

Published: Tuesday, 24 August 2021 at 12:00 am<\/p>

\n\n

A few Octobers ago, my family and I were visiting some friends in the mountains of Vermont. After dinner, I went out to get a better look at the skies.<\/p>\n

The dark in their small town is deep and all-encompassing; a very welcome change from the light-polluted and washed-out skies of my over-lit railroad town.<\/p>\n

Before long, as I strolled along staring at Mars<\/a>, I was more concerned about coming across a bear than I was about where I walked.<\/p>\n

I had no idea how to get back; no signal on my mobile phone, either. I was lost.<\/p>\n

It\u2019s always interesting to me how very dark and starry skies can be disorienting. They\u2019re wonderful, no doubt, but with so many stars<\/a> around, it\u2019s sometimes hard to pick out the familiar ones.<\/p>\n

Light pollution causes its own problems, but it also manages to highlight the sky\u2019s brightest stars.<\/p>\n

\""A\"<\/div>
A starry night sky is a glorious sight, but can be overwhelming if you need to pick out a specific target. Credit:\u00a0 Paul Scott, Cheshire, UK.<\/span><\/figcaption><\/div>\n

Navigating using the stars<\/strong><\/h1>\n

Sailors have used the stars to guide them for pretty much as long as there have been sailors to be guided by them, but as time has gone on, that set of skills has fallen away for most of us.<\/p>\n

Still, here in the northern hemisphere, we\u2019re fortunate and have one trick left up all of our sleeves.<\/p>\n

We have an easy tool to find our way around the night sky, or to guide us home when we\u2019ve spent too much time watching Mars and avoiding bears.<\/p>\n

If you can find Polaris, the North Star, you can find north.<\/p>\n

\""Sailors\"<\/div>
Sailors have used the stars to navigate their way for centuries. Credit: Samuli Vainionp\u00e4\u00e4 \/ Getty<\/span><\/figcaption><\/div>\n

What is the North Star?<\/strong><\/h1>\n

The star Polaris<\/strong> (\u03b1 UMi) is called the North Star because it\u2019s very close to, though not exactly on, the north celestial pole.<\/p>\n

That\u2019s the spot we\u2019d be looking at if we were to take Earth\u2019s north pole and stretch it way off into space: Polaris is almost exactly due north.<\/p>\n

Because the whole sky seems to rotate round this region, it\u2019s often used by astrophotographers to shoot star trail images<\/a>.<\/p>\n

\""Peter\"<\/div>
Peter Longden captured these star trails around Polaris from Buckinghamshire in the UK. Peter used a Canon EOS 5D Mark IV DSLR camera and 24mm lens.<\/span><\/figcaption><\/div>\n

Close up, Polaris would appear as a giant star about with five times the Sun\u2019s mass and two other stars that are around the same mass as the Sun.<\/p>\n

As long as we can find that star, it\u2019s easy to figure out where we are and what direction we\u2019re looking. The other cardinal directions are just as easy to figure out from there.<\/p>\n

What\u2019s more, since it\u2019s so close to the north celestial pole, Polaris always at the same altitude above the horizon as your latitude.<\/p>\n

For example, in London, which is at about 51\u00b0 north latitude, we can see Polaris about 51\u00b0 above the horizon.<\/p>\n

Meanwhile, where I live Polaris is lower, around 41 degrees from the horizon.<\/p>\n

How to find Polaris, the North Star<\/strong><\/h1>\n
\""How\"<\/div>
The Plough asterism. Credit: Bernhard Hubl \/ CCDGuide.com<\/span><\/figcaption><\/div>\n

Though Polaris is one of the most famous stars in the night, it is by no means the brightest star in the night sky<\/a>.<\/p>\n

It isn\u2019t as bright as many of us expect. Truth is, it\u2019s only about the 50th brightest star in the sky.<\/p>\n

It can even be a little tough to find in brightly lit suburban or city skies where the rest of its constellation, Ursa Minor (the lesser bear) is often nearly completely washed away.<\/p>\n

From the 430 or so lightyears from us to it, it appears as a single, second-magnitude dot in the night.<\/p>\n

We don\u2019t need to be lost in the mountains to look for the North Star, though. In fact, I usually start my evenings looking for it, even if I\u2019m in my own yard.<\/p>\n

\""The\"<\/div>
The Plough\u2019s stars are a great first target from which you can star-hop to other constellations, including Ursa Minor, which contains the North Star or Pole Star. Credit: BBC Sky at Night Magazine.<\/span><\/figcaption><\/div>\n

Most of us know how to find the Plough<\/strong>, so let\u2019s start there.<\/p>\n

The Plough\u2019s reliably in the sky every night, though it changes its position depending on the time of year, and the time of night, we look.<\/p>\n

For much of the northern hemisphere, all the stars in this region of the sky are circumpolar. <\/em><\/p>\n

This means they\u2019re so far to the north that they don\u2019t rise and set as other stars do, and they don\u2019t come and go with the seasons.<\/p>\n

Instead, they\u2019re in the sky every night of the year and never set. They just get overwhelmed by bright sunlight every day, and then reappear through the twilight each night.<\/p>\n

Cassoipeia<\/strong><\/a>, Cepheus<\/strong>, Draco<\/strong>\u00a0and objects in that part of the sky are also all circumpolar, and it\u2019s exciting to show people who are new to the skies how to find those, too.<\/p>\n

\""The\"<\/div>
Merak and Dubhe are also known as the \u2018Pointers\u2019, because they point to Polaris, the North Star.<\/span><\/figcaption><\/div>\n

\u00a0<\/p>\n

Once we\u2019ve found the Plough, all we need to do is draw a line between Merak<\/strong><\/a> (\u03b2 UMa) and Dubhe <\/strong>(\u03b1 UMa), the two stars at the end of the Plough\u2019s blade, and then out through the blade\u2019s top.\u00a0The next fairly bright star we see is Polaris.<\/p>\n

That\u2019s all there is to it, and once we find it, we\u2019re on our way!\u00a0East is to our right, west to the left, and south is behind us.<\/p>\n

It was just a couple quick turns and a few minutes\u2019 walk before I was back at my friends\u2019 place.<\/p>\n

Will Polaris always be the North Star?<\/strong><\/h1>\n
\""Vega\"<\/div>
Vega by Jamie Bowring, Devon, UK. Equipment: SW 150p, Canon 30D<\/span><\/figcaption><\/div>\n

Polaris hasn\u2019t always been the North Star, and it won\u2019t always be the North Star.<\/p>\n

Earth\u2019s axis wobbles a little bit. Over time, thanks to this precession<\/em>, it points toward different stars over a 26,000-year cycle.<\/p>\n

About 12,000 years ago, it pointed towards Vega<\/strong> (\u03b1 Lyr) in the constellation Lyra, and also part of the Summer Triangle asterism<\/a> (one of our favourite summer constellations<\/a> and asterisms).<\/p>\n

Though things look steady now, our axis is gradually drifting so that in about 12,000 years Vega will become the north star again.<\/p>\n

While our stellar navigation skills aren\u2019t what they used to be, we can still rely Polaris to guide us home and learn our way around the northern part of the sky. Plus it\u2019s a great party trick.<\/p>\n

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By Scott Levine Published: Tuesday, 24 August 2021 at 12:00 am A few Octobers ago, my family and I were visiting some friends in the mountains of Vermont. After dinner, I went out to get a better look at the skies. The dark in their small town is deep and all-encompassing; a very welcome change […]<\/p>\n","protected":false},"author":24,"featured_media":0,"template":"","categories":[1],"acf":{"readingTimeMinutes":"6"},"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false},"uagb_author_info":{"display_name":"importmanagerhub@sprylab.com","author_link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/author\/importmanagerhubsprylab-com\/"},"uagb_comment_info":0,"uagb_excerpt":"By Scott Levine Published: Tuesday, 24 August 2021 at 12:00 am A few Octobers ago, my family and I were visiting some friends in the mountains of Vermont. After dinner, I went out to get a better look at the skies. The dark in their small town is deep and all-encompassing; a very welcome change…","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/rss_feed\/23180"}],"collection":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/rss_feed"}],"about":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/types\/rss_feed"}],"author":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/users\/24"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=23180"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=23180"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}