{"id":27949,"date":"2022-01-20T00:00:00","date_gmt":"2022-01-20T00:00:00","guid":{"rendered":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/?post_type=purple_issue&p=27949"},"modified":"2022-02-02T15:11:41","modified_gmt":"2022-02-02T15:11:41","slug":"star-of-the-month-5","status":"publish","type":"post","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/2022\/01\/20\/star-of-the-month-5\/","title":{"rendered":"Star of the month"},"content":{"rendered":"\n

Discover Mirzam, Canis Major\u2019s \u2018herald\u2019<\/p>\n\n

\"\"
Look for the blue-white star Mirzam, west and south of bright Sirius<\/figcaption><\/figure><\/div>\n\n

Although Mirzam (Beta (\u03b2) Canis Majoris), shines at mag. +2.0, it\u2019s outshone by its sky neighbour, mag. \u20131.5 Sirius (Alpha (\u03b1) Canis Majoris).<\/p>\n\n

Mirzam lies 5.5\u02da west and a bit south of Sirius and is easy to identify for this reason. Its name is derived from the Arabic term meaning \u2018The Herald\u2019, thought to refer to the fact that it rises just before Sirius, so heralding or announcing the appearance of its neighbour. Mirzam is the fourth brightest star in Canis Major, the Great Dog.<\/p>\n\n

Sirius may appear to dominate over Mirzam in terms of brightness, but the pair are an example of how the apparent sky we see is deceptive. Sirius is located 8.7 lightyears away from the Sun. Mirzam is a more distant star, estimated to be 490 lightyears away. Although Sirius appears to be 24 times brighter to us in the sky, Mirzam is 56 times further away. If you were to place them at a standard distance of 10 parsecs, or 32.62 lightyears, Sirius would have an absolute magnitude of +1.4 while Mirzam would appear at mag. \u20134.1, similar to how bright Venus appears from Earth. If you were to place Mirzam at the distance of Sirius, it would shine 15 times brighter than Venus appears to us!<\/span><\/p>\n\n

Mirzam has a spectral type of B1 II-III, a hot, blue, bright giant star. Its temperature has been measured at 25,527\u02daC, which means that a lot of its radiative output is in the spectrum\u2019s ultraviolet part. By comparison, it\u2019s 14 times more massive, 10 times larger and <\/span>has a luminosity around 26,600 times larger than the Sun. Its also variable, the brightest member of the Beta Cephei class of variables.<\/p>\n\n

Photo: PETE LAWRENCE<\/p>\n","protected":false},"excerpt":{"rendered":"

Discover Mirzam, Canis Major\u2019s \u2018herald\u2019<\/p>\n","protected":false},"author":24,"featured_media":27948,"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":"February-2022","purple_custom_meta_purple_source_issue":"February-2022","purple_external_id":"February-2022-53-2","purple_custom_meta_purple_external_id":"February-2022-53-2","purple_issue_code":"|0000086549||","purple_custom_meta_purple_issue_code":"|0000086549||","purple_android_product":"com.im.skyatnight.201","purple_custom_meta_purple_android_product":"com.im.skyatnight.201","purple_ios_product":"com.im.skyatnight.201","purple_custom_meta_purple_ios_product":"com.im.skyatnight.201","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\/01\/213feb17-89bc-477f-8dc6-922983adca41.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\/01\/213feb17-89bc-477f-8dc6-922983adca41.jpg",1025,842,false],"thumbnail":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/01\/213feb17-89bc-477f-8dc6-922983adca41-150x150.jpg",150,150,true],"medium":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/01\/213feb17-89bc-477f-8dc6-922983adca41-300x246.jpg",300,246,true],"medium_large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/01\/213feb17-89bc-477f-8dc6-922983adca41-768x631.jpg",768,631,true],"large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/01\/213feb17-89bc-477f-8dc6-922983adca41.jpg",800,657,false],"1536x1536":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/01\/213feb17-89bc-477f-8dc6-922983adca41.jpg",1025,842,false],"2048x2048":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/01\/213feb17-89bc-477f-8dc6-922983adca41.jpg",1025,842,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":"Discover Mirzam, Canis Major\u2019s \u2018herald\u2019","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/27949"}],"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=27949"}],"version-history":[{"count":3,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/27949\/revisions"}],"predecessor-version":[{"id":28691,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/27949\/revisions\/28691"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media\/27948"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=27949"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=27949"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/tags?post=27949"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}