{"id":29039,"date":"2022-02-10T00:00:00","date_gmt":"2022-02-10T00:00:00","guid":{"rendered":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/?post_type=purple_issue&p=29039"},"modified":"2022-03-23T13:17:43","modified_gmt":"2022-03-23T13:17:43","slug":"star-of-the-month-6","status":"publish","type":"post","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/2022\/02\/10\/star-of-the-month-6\/","title":{"rendered":"Star of the month"},"content":{"rendered":"\n

Find Altarf, at the end of the Crab’s leg<\/p>\n\n

\"\"
The brightest star in Cancer is Altarf (Beta (\u03b2) Cancri), which is 290 lightyears away<\/figcaption><\/figure><\/div>\n\n

As a constellation, it has to be said that Cancer isn\u2019t one of the most impressive. Yes, it contains the open cluster M44, also known as the Beehive Cluster, and there\u2019s another fainter open cluster near Acubens (Alpha (\u03b1) Cancri) called M67, but the stars that form the Zodiacal Crab of Cancer are pretty faint.<\/p>\n\n

The brightest isn\u2019t Acubens as you might think, but Altarf (Beta (\u03b2) Cancri) which marks the southwest point of the constellation\u2019s inverted Y-shaped pattern. The name is from the Arabic \u2018Al Tarf \u2019 <\/em>meaning \u2018the End\u2019, and it represents one of the Crab\u2019s legs.<\/p>\n\n

Altarf has a spectral type of K4III Ba1, a cool orange K4 class giant with abundances of barium (chemical symbol Ba).<\/span> Its effective temperature is 3,717\u02daC, which is much cooler than our Sun at 5,505\u02daC.<\/p>\n\n

Located at a distance of 290 lightyears, Altarf shines at mag. +3.5. Despite its diminutive status, it should be borne in mind that Altarf is still 61 times larger and 870 times more luminous than the Sun.<\/p>\n\n

A faint red-dwarf companion accompanies the main star. Shining at 14th magnitude, it is estimated to lie around 2,600 AU from Altarf; that\u2019s around 65 times the Sun-Pluto distance. The orbital period is estimated to be 76,000 years, but no evidence for any mutual orbital motion has been confirmed yet.<\/span><\/p>\n\n

Altarf is also believed to have a planet. Discovered in 2014, this body is estimated to be nearly eight times the mass of Jupiter, orbiting the star once every 605 days at an average distance of 1.7 AU.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

Find Altarf, at the end of the Crab’s leg<\/p>\n","protected":false},"author":24,"featured_media":29038,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ub_ctt_via":"","purple_page_number":"53","purple_custom_meta_purple_page_number":"53","purple_seq_number":"2","purple_custom_meta_purple_seq_number":"2","purple_source_article":"article_53-2.xml","purple_custom_meta_purple_source_article":"article_53-2.xml","purple_source_issue":"March-2022","purple_custom_meta_purple_source_issue":"March-2022","purple_external_id":"March-2022-53-2","purple_custom_meta_purple_external_id":"March-2022-53-2","purple_issue_code":"|0000086550||","purple_custom_meta_purple_issue_code":"|0000086550||","purple_android_product":"com.im.skyatnight.202","purple_custom_meta_purple_android_product":"com.im.skyatnight.202","purple_ios_product":"com.im.skyatnight.202","purple_custom_meta_purple_ios_product":"com.im.skyatnight.202","purple_web_product":"","purple_custom_meta_purple_web_product":"","purple_publication_id":"075fab74-0a21-4201-866a-899d6c41c40c","purple_migrated":"","kt_blocks_editor_width":""},"categories":[22],"tags":[14],"featured_image_src":"https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/02\/96df3f6f-c7e3-4f6f-bbcb-c79d6694145f.jpg","author_info":{"display_name":"importmanagerhub@sprylab.com","author_link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/author\/importmanagerhubsprylab-com\/"},"acf":{"readingTimeMinutes":"2","apple_news_title":""},"uagb_featured_image_src":{"full":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/02\/96df3f6f-c7e3-4f6f-bbcb-c79d6694145f.jpg",1045,860,false],"thumbnail":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/02\/96df3f6f-c7e3-4f6f-bbcb-c79d6694145f-150x150.jpg",150,150,true],"medium":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/02\/96df3f6f-c7e3-4f6f-bbcb-c79d6694145f-300x247.jpg",300,247,true],"medium_large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/02\/96df3f6f-c7e3-4f6f-bbcb-c79d6694145f-768x632.jpg",768,632,true],"large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/02\/96df3f6f-c7e3-4f6f-bbcb-c79d6694145f-1024x843.jpg",800,659,true],"1536x1536":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/02\/96df3f6f-c7e3-4f6f-bbcb-c79d6694145f.jpg",1045,860,false],"2048x2048":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/02\/96df3f6f-c7e3-4f6f-bbcb-c79d6694145f.jpg",1045,860,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":"Find Altarf, at the end of the Crab's leg","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/29039"}],"collection":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/users\/24"}],"replies":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/comments?post=29039"}],"version-history":[{"count":3,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/29039\/revisions"}],"predecessor-version":[{"id":29735,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/29039\/revisions\/29735"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media\/29038"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=29039"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=29039"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/tags?post=29039"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}