{"id":41022,"date":"2023-01-26T14:50:12","date_gmt":"2023-01-26T14:50:12","guid":{"rendered":"https:\/\/www.skyatnightmagazine.com\/?p=115589"},"modified":"2023-01-26T15:32:39","modified_gmt":"2023-01-26T15:32:39","slug":"how-to-see-dubhe-one-of-the-ploughs-pointer-stars","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/rss_feed\/how-to-see-dubhe-one-of-the-ploughs-pointer-stars\/","title":{"rendered":"How to see Dubhe, one of the Plough\u2019s pointer stars"},"content":{"rendered":"

<\/p>

By Pete Lawrence\n \t\t<\/p>

Published: Thursday, 26 January 2023 at 12:00 am<\/p>

\n\n

Dubhe (Alpha (\u03b1<\/span>) Ursae Majoris) is one of the pointer stars in the familiar asterism<\/a> known as the Plough or Saucepan.<\/p>\n

It marks the northeast corner of the Plough<\/a>\u2019s blade or Saucepan\u2019s pan however you see it.<\/p>\n

The second pointer star is Merak<\/a> (Beta (\u03b2<\/span>) Ursae Majoris). A line extended from Merak through Dubhe eventually brings you to the North Star<\/a>, Polaris (Alpha (\u03b1<\/span>) Ursae Minoris); hence the term \u2018Pointers\u2019.<\/p>\n

\"""\"<\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/picture><\/div>
Among the Plough\u2019s best-known stars are the double star (Mizar and Alcor) and \u2018The Pointers\u2019 (Merak and Dubhe) which help to locate Polaris. Credit: Pete Lawrence.<\/span><\/figcaption><\/div>\n

Facts about star Dubhe<\/strong><\/h2>\n

Dubhe shines at mag. +1.8 and is located 123 lightyears from the Sun.<\/p>\n

Despite its designation as Alpha Ursae Majoris, Dubhe is actually the second brightest star in Ursa Major.<\/p>\n

The brightest is Alioth (Epsilon (\u03b5<\/span>) Ursae Majoris), the third star in from the end of the Plough\u2019s handle.<\/p>\n

The reason for the non-brightness lettering sequence is that Bayer labelled the stars in the Plough from east to west.<\/p>\n

Consequently, if you know the first seven letters of the Greek alphabet \u2013 alpha (\u03b1<\/span>), beta (\u03b2<\/span>), gamma (\u03b3<\/span>), delta (\u03b4<\/span>), epsilon (\u03b5<\/span>), zeta (\u03b6<\/span>), eta (\u03b7<\/span>) \u2013 then you can deduce the Bayer designation of the stars in the Plough easily.<\/p>\n

\"""\"<\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/picture><\/div>\n

Of the seven stars that form the Plough, the inner-five, Beta (\u03b2<\/span>), Gamma (\u03b3<\/span>), Delta (\u03b4<\/span>), Epsilon (\u03b5<\/span>) and Zeta (\u03b6<\/span>) Ursae Majoris are all part of a cluster located at a distance of 80 lightyears.<\/p>\n

Dubhe and Alkaid (Eta (\u03b7<\/span>) Ursae Majoris) aren\u2019t part of this cluster and over time will move in different directions to the other five stars.\u00a0<\/span><\/p>\n

Of the seven stars Dubhe is the coolest, the other six being hot blue-white stars.<\/span><\/p>\n

Dubhe has a spectral class<\/a> of K0III, indicating that it\u2019s an orange giant star. When you look at the Plough see if you can spot the difference in colour between Dubhe and the other stars in the pattern.\u00a0<\/span><\/span><\/p>\n

Dubhe is a spectroscopic binary star<\/a> system. The primary, Dubhe A, is 4.3 times as massive as the Sun, the secondary 1.6 times.<\/p>\n

Dubhe A is also over 300 times more luminous than the Sun. The name Dubhe derives from \u2018the bear\u2019 in Arabic.<\/p>\n

This guide originally appeared in the April 202o issue of <\/strong><\/em>BBC Sky at Night Magazine<\/strong>.<\/strong><\/em><\/p> <\/body><\/html>\n

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By Pete Lawrence Published: Thursday, 26 January 2023 at 12:00 am Dubhe (Alpha (\u03b1) Ursae Majoris) is one of the pointer stars in the familiar asterism known as the Plough or Saucepan. It marks the northeast corner of the Plough\u2019s blade or Saucepan\u2019s pan however you see it. The second pointer star is Merak (Beta […]<\/p>\n","protected":false},"author":24,"featured_media":41023,"template":"","categories":[1],"acf":{"readingTimeMinutes":"2"},"uagb_featured_image_src":{"full":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2023\/01\/how-to-see-dubhe-one-of-the-ploughs-pointer-stars.jpg",1200,800,false],"thumbnail":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2023\/01\/how-to-see-dubhe-one-of-the-ploughs-pointer-stars-150x150.jpg",150,150,true],"medium":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2023\/01\/how-to-see-dubhe-one-of-the-ploughs-pointer-stars-300x200.jpg",300,200,true],"medium_large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2023\/01\/how-to-see-dubhe-one-of-the-ploughs-pointer-stars-768x512.jpg",768,512,true],"large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2023\/01\/how-to-see-dubhe-one-of-the-ploughs-pointer-stars-1024x683.jpg",800,534,true],"1536x1536":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2023\/01\/how-to-see-dubhe-one-of-the-ploughs-pointer-stars.jpg",1200,800,false],"2048x2048":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2023\/01\/how-to-see-dubhe-one-of-the-ploughs-pointer-stars.jpg",1200,800,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 Pete Lawrence Published: Thursday, 26 January 2023 at 12:00 am Dubhe (Alpha (\u03b1) Ursae Majoris) is one of the pointer stars in the familiar asterism known as the Plough or Saucepan. It marks the northeast corner of the Plough\u2019s blade or Saucepan\u2019s pan however you see it. The second pointer star is Merak (Beta…","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/rss_feed\/41022"}],"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:featuredmedia":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media\/41023"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=41022"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=41022"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}