{"id":26185,"date":"2021-11-18T11:30:53","date_gmt":"2021-11-18T11:30:53","guid":{"rendered":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/?post_type=purple_issue&p=26185"},"modified":"2021-11-18T11:30:53","modified_gmt":"2021-11-18T11:30:53","slug":"deep-sky-tour-3","status":"publish","type":"post","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/2021\/11\/18\/deep-sky-tour-3\/","title":{"rendered":"Deep-sky tour"},"content":{"rendered":"\n

This month\u2019s deep-sky tour visits objects in Orion, including a number ’37’ star formation<\/p>\n\n

\"\"<\/figure><\/div>\n\n
1. Collinder 69<\/strong><\/h5>\n\n

Recommended equipment: Small\/medium telescope<\/strong><\/p>\n\n

Orion\u2019s head is marked by mag. +3.4 Meissa (Lambda (\u03bb) Orionis). This marks the northern vertex of a small naked-eye triangle, together with mag. +4.4 Phi 1 <\/sup>(\u03c6 ) Orionis and mag. +4.1 Phi (\u03c6 ) Orionis. A small scope at low power shows numerous fainter stars in the region, many belonging to cluster Collinder 69. Look out for the attractive line of seventh magnitude stars running south of Meissa.<\/p>\n\n

Telescopes over 250mm may detect faint nebulosity around the cluster. This is Sharpless 2-264, an object made easier to see with an Oxygen (OIII) filter. It occupies a roughly circular area 6.5\u02da across, centred on Meissa and has low surface brightness, with the brightest part west of Meissa. Long exposure images reveal the Angel Fish Nebula; a pink emission nebula that resembles a sideways-on fish.<\/p>\n\n

2. NGC 2022 <\/strong><\/h5>\n\n

Recommended equipment: Small\/medium or large telescope<\/strong><\/p>\n\n

Our next object appears within the boundary of Sharpless 2-264, 1.9\u02da eastsoutheast of Meissa. Here lies the brightest planetary nebula in Orion, NGC 2022, which isn\u2019t saying much as it shines with an integrated magnitude of +12.4! It has an apparent diameter of 20 arcseconds, with small scopes revealing a star-like object at low magnification. Upping the power won\u2019t show detail, but should reveal the elliptical shape of this planetary.<\/span><\/p>\n\n

Larger instruments show a grey ellipse with a darker region in the centre that creates the appearance of a ring. The central star has a mag. +14.9 and requires at least 400mm of aperture to see properly. <\/p>\n\n

\"\"
The stars in open cluster NGC 2169 are likened to a number \u201837\u2019 and a shopping trolley<\/figcaption><\/figure><\/div>\n\n
3. Abell 12<\/strong><\/h5>\n\n

Recommended equipment: Large telescope<\/strong><\/p>\n\n

The Abell catalogue of planetary nebulae lists 86 objects, many of which are faint and require large scopes. Abell 12 adds to the challenge as it\u2019s located near Mu (\u03bc) Orionis. Mu shines at mag. +4.1 while the integrated magnitude of Abell 12 is +13.9, over 8,000 times dimmer than the star. Abell 12 is around 0.5 arcminutes from Mu and falls within its visual glare, making the planetary difficult to see, even with a large instrument. Nicknamed the \u2018hidden planetary\u2019, the trick is to employ a large aperture and an OIII filter.<\/span><\/p>\n\n

4. NGC 2141<\/strong><\/h5>\n\n

Recommended equipment: Small\/medium or large telescope<\/strong><\/p>\n\n

Open cluster NGC 2141 sits 0.8\u02da north and a bit east of Mu Orionis. When the term \u2018open cluster\u2019 is mentioned, the mind\u2019s eye image is of a group of<\/span> stars in the eyepiece. However, not all are bright enough to show such a view and NGC 2141 falls into this category. Despite being listed at mag. +9.4, smaller instruments are unable to resolve any of the cluster\u2019s stars; you will see a mistiness behind a number of brighter foreground stars. You need a 300mm aperture to show the 20 individually resolved stars. <\/p>\n\n

5. NGC 2194<\/strong><\/h5>\n\n

Recommended equipment: Small\/medium or large telescope<\/strong><\/p>\n\n

Located 3.5\u02da northwest of NGC 2141 and half a degree northwest of the mag. +5.4 star 73 Orionis, is the open cluster NGC 2194. This has a similar size to our previous target, but is slightly brighter with a listed integrated magnitude of +8.5. A 150mm scope shows a misty glow sprinkled with six or so individual stars. A 250mm scope doubles the number of individual stars seen and reveals a granular texture to the mistiness, while a 300mm scope allows you to drill down into the cluster\u2019s core where several tens of stars can be individually resolved. <\/span><\/p>\n\n

6. NGC 2169 <\/strong><\/h5>\n\n

Recommended equipment: Small\/medium or large telescope<\/strong><\/p>\n\n

The stars in our final object appear to form the number \u201837\u2019 or perhaps less attractively, a shopping trolley! Listed at mag. +5.9, a small scope will show NGC 2169, containing 16 stars in a 5 arcsecond area. The count increases to around 20 cluster members through a 300mm telescope. Look for the contrast in colour between most of the stars and the two which mark the join between the vertical and horizontal components of the \u20187\u2019. This pair is double star Struve 844 and looks orange compared to the white and blue-white colour of the others. The brightest star in the top of the \u20183\u2019 is double star Struve 848, with mag. +6.9 and +7.8 components separated by 2.6 arcseconds.<\/p>\n\n

<\/div>
\n

More ONLINE <\/strong><\/h4>\n\n\n\n

Print out this chart and take an automated Go-To tour. <\/strong><\/p>\n<\/div><\/section>\n\n

This Deep-Sky Tour has been automated <\/strong>ASCOM-enabled Go-To mounts can now take you to this month\u2019s targets at the touch of a button, with our Deep-Sky Tour file for the EQTOUR app. Find it online.<\/p>\n\n

PHOTS G\u00dcNTER KERSCHHUBER\/CCDGUIDE.COM, CHART BY PETE LAWRENCE<\/p>\n","protected":false},"excerpt":{"rendered":"

This month\u2019s deep-sky tour visits objects in Orion, including a number ’37’ star formation<\/p>\n","protected":false},"author":24,"featured_media":26182,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ub_ctt_via":"","purple_page_number":"56","purple_custom_meta_purple_page_number":"56","purple_seq_number":"1","purple_custom_meta_purple_seq_number":"1","purple_source_article":"article_56-1.xml","purple_custom_meta_purple_source_article":"article_56-1.xml","purple_source_issue":"December-2021","purple_custom_meta_purple_source_issue":"December-2021","purple_external_id":"December-2021-56-1","purple_custom_meta_purple_external_id":"December-2021-56-1","purple_issue_code":"|0000086547||","purple_custom_meta_purple_issue_code":"|0000086547||","purple_android_product":"com.im.skyatnight.199","purple_custom_meta_purple_android_product":"com.im.skyatnight.199","purple_ios_product":"com.im.skyatnight.199","purple_custom_meta_purple_ios_product":"com.im.skyatnight.199","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\/2021\/11\/f2d5ea72-3b45-4044-aa0e-bf231aea2e42.jpg","author_info":{"display_name":"importmanagerhub@sprylab.com","author_link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/author\/importmanagerhubsprylab-com\/"},"acf":{"readingTimeMinutes":"4","apple_news_title":""},"uagb_featured_image_src":{"full":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2021\/11\/f2d5ea72-3b45-4044-aa0e-bf231aea2e42.jpg",780,780,false],"thumbnail":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2021\/11\/f2d5ea72-3b45-4044-aa0e-bf231aea2e42-150x150.jpg",150,150,true],"medium":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2021\/11\/f2d5ea72-3b45-4044-aa0e-bf231aea2e42-300x300.jpg",300,300,true],"medium_large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2021\/11\/f2d5ea72-3b45-4044-aa0e-bf231aea2e42-768x768.jpg",768,768,true],"large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2021\/11\/f2d5ea72-3b45-4044-aa0e-bf231aea2e42.jpg",780,780,false],"1536x1536":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2021\/11\/f2d5ea72-3b45-4044-aa0e-bf231aea2e42.jpg",780,780,false],"2048x2048":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2021\/11\/f2d5ea72-3b45-4044-aa0e-bf231aea2e42.jpg",780,780,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":"This month\u2019s deep-sky tour visits objects in Orion, including a number '37' star formation","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/26185"}],"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=26185"}],"version-history":[{"count":5,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/26185\/revisions"}],"predecessor-version":[{"id":26772,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/26185\/revisions\/26772"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media\/26182"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=26185"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=26185"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/tags?post=26185"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}