{"id":38187,"date":"2022-11-11T00:00:00","date_gmt":"2022-11-11T00:00:00","guid":{"rendered":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/?post_type=purple_issue&p=38187"},"modified":"2022-11-25T12:41:38","modified_gmt":"2022-11-25T12:41:38","slug":"deep-sky-tour-15","status":"publish","type":"post","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/2022\/11\/11\/deep-sky-tour-15\/","title":{"rendered":"Deep-sky tour"},"content":{"rendered":"\n

We explore the best celestial sights around Aries, Pisces and Triangulum <\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n
1. NGC 821<\/strong><\/h5>\n\n\n\n

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

Our starting object is mag. +11.3 NGC 821, an elliptical galaxy in the extreme southwest corner of Aries, 12.5\u00b0 south of mag. +2.0 Hamal (Alpha (\u03b1) Arietis). A mag. +9.2 foreground star lies a fraction to the west-northwest of the galaxy\u2019s centre. Even in a 250mm scope, NGC 821 is little more than a smudge, 1.4×0.6 arcminutes across and elongated from southwest\u2013northeast. A 300mm scope doesn\u2019t pull a great deal more from this galaxy. Start off with medium magnification to reveal that the galaxy seems to concentrate towards a star-like nucleus. This is particularly evident at higher magnifications, but increased power won\u2019t do the outer halo any favours. <\/p>\n\n\n\n

2. NGC 772<\/strong><\/h5>\n\n\n\n

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

We head north towards the three stars that form the most recognisable part of Aries to find the unbarred spiral galaxy NGC 772. This shines at mag. +11.1 and unlike NGC 821 is visible in smaller scopes. It lies 1.4\u00b0 to the east of Mesarthim (Gamma (\u03b3) Arietis) and shows as an oval glow with a defined core that brightens to a star-like nucleus through a 150mm scope, and appears distinctly mottled with larger apertures. A 300mm scope shows an object 3.5×1.5 arcminutes in size. The galaxy\u2019s seemingly diminutive appearance from Earth is misleading. Located 130 million lightyears from us, this object is estimated to be around twice the size of our own Milky Way Galaxy! <\/p>\n\n\n\n

3. M74 <\/strong><\/h5>\n\n\n\n

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

Heading next door into Pisces, 2.4\u00b0 west of the western Aries border we find face-on spiral M74. The guide point here is to imagine a line from Hamal to Sheratan (Beta (\u03b2) Arietis). Extend it almost twice that distance again to reach mag. +4.0 Eta (\u03b7) Piscium; M74 lies 1.3\u00b0 to its east-northeast. A small instrument shows a slightly elongated patch of light 6 arcminutes across that gently brightens towards the centre. A 250mm scope reveals a larger patch, 8 arcminutes across with more pronounced elongation with an east\u2013west orientation. The core appears slightly off-centre. A large aperture reveals a prominent granular centre and a beautifully mottled outer halo, full of faint detail. <\/span><\/p>\n\n\n\n

\"\"
Unbarred spiral galaxy NGC 772 with its distinctive elongated arm is twice as big as our Galaxy<\/figcaption><\/figure><\/div>\n\n\n\n
4. NGC 697 <\/strong><\/h5>\n\n\n\n

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

We return to the Aries grouping of three main stars, Hamal, Sheratan and Mesarthim, for NGC 697. It\u2019s located 1.7\u00b0 to the northwest of Sheratan, 0.3\u00b0 to the northeast of the double star 1 Arietis, whose component magnitudes are +5.8 and +7.1. Presumably due to a mix-up somewhere down the line, NGC 697 is also known as NGC 674. A small scope shows an object with a definite core around 1 arcminute across, which grows only slightly through a 250mm scope, which also reveals an elongated core. A 300mm instrument shows a marginally larger galaxy of 2.0×1.0 arcminutes, elongated east\u2013west. <\/span><\/p>\n\n\n\n

5. Collinder 21<\/strong><\/h5>\n\n\n\n

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

We head north out of Aries for the open cluster Collinder 21. It is located 4.6\u00b0 to the north of NGC 697 and 0.6\u00b0 north of mag. +6.9 HIP 8490 in Triangulum. At 9 arcminutes across and mag. +8.2, a small telescope won\u2019t have any trouble finding the stars that make up this tight group. Its brightest stars form a shape reminiscent of the semi-circular constellation Corona Borealis and range from eighth to 11th magnitude. Pretty though it appears, Collinder 21 isn\u2019t a true cluster at all but simply an asterism, a line-of-sight arrangement of stars. About 15 stars populate the \u2018cluster\u2019 zone. <\/p>\n\n\n\n

6. NGC 672\/IC 1727 <\/strong><\/h5>\n\n\n\n

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

There are several galaxies surrounding Collinder 21, including spiral galaxy NGC 672 located 0.5\u00b0 to the northwest. Shining at mag. +11.1, it is visible in small telescopes as a featureless elongated glow, brightening at its core. A 250mm scope shows an asymmetrical outer envelope measuring 4×1.5 arcminutes. Larger apertures reveal its core to be uneven in brightness and almost knotted in parts. NGC 672 forms an interacting pair with IC 1727, an irregular galaxy of similar apparent size immediately to its southwest. At mag. +11.6, IC 1727 is virtually invisible to smaller scopes. Larger instruments just show a glowing patch 3×1.5 arcminutes in size. <\/p>\n\n\n\n

<\/div>
\n

More ONLINE <\/strong>
Print out this chart and take an automated Go-To tour.
www.skyatnightmagazine.com\/bonus-content\/PF5NNHB<\/a><\/p>\n<\/div><\/section>\n","protected":false},"excerpt":{"rendered":"

We explore the best celestial sights around Aries, Pisces and Triangulum <\/p>\n","protected":false},"author":24,"featured_media":38529,"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":"2","purple_custom_meta_purple_seq_number":"2","purple_source_article":"article_56-2.xml","purple_custom_meta_purple_source_article":"article_56-2.xml","purple_source_issue":"December-2022","purple_custom_meta_purple_source_issue":"December-2022","purple_external_id":"December-2022-56-2","purple_custom_meta_purple_external_id":"December-2022-56-2","purple_issue_code":"|0000086559||","purple_custom_meta_purple_issue_code":"|0000086559||","purple_android_product":"com.im.skyatnight.211","purple_custom_meta_purple_android_product":"com.im.skyatnight.211","purple_ios_product":"com.im.skyatnight.211","purple_custom_meta_purple_ios_product":"com.im.skyatnight.211","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\/11\/85251054-b545-43a1-b2af-8569c95d0a7d-rotated.jpeg","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\/2022\/11\/85251054-b545-43a1-b2af-8569c95d0a7d-rotated.jpeg",2048,1508,false],"thumbnail":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/11\/85251054-b545-43a1-b2af-8569c95d0a7d-150x150.jpeg",150,150,true],"medium":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/11\/85251054-b545-43a1-b2af-8569c95d0a7d-300x221.jpeg",300,221,true],"medium_large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/11\/85251054-b545-43a1-b2af-8569c95d0a7d-768x566.jpeg",768,566,true],"large":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/11\/85251054-b545-43a1-b2af-8569c95d0a7d-1024x754.jpeg",800,589,true],"1536x1536":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/11\/85251054-b545-43a1-b2af-8569c95d0a7d-1536x1131.jpeg",1536,1131,true],"2048x2048":["https:\/\/c01.purpledshub.com\/uploads\/sites\/77\/2022\/11\/85251054-b545-43a1-b2af-8569c95d0a7d-rotated.jpeg",2048,1508,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":"We explore the best celestial sights around Aries, Pisces and Triangulum","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/38187"}],"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=38187"}],"version-history":[{"count":6,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/38187\/revisions"}],"predecessor-version":[{"id":39469,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/posts\/38187\/revisions\/39469"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media\/38529"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=38187"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=38187"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/tags?post=38187"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}