{"id":92666,"date":"2023-02-22T18:15:11","date_gmt":"2023-02-22T17:15:11","guid":{"rendered":"https:\/\/www.astb.se\/cassiopeiabloggen\/?p=92666"},"modified":"2023-02-22T18:16:59","modified_gmt":"2023-02-22T17:16:59","slug":"nr-16-2023","status":"publish","type":"post","link":"https:\/\/www.astb.se\/cassiopeiabloggen\/2023\/02\/22\/nr-16-2023\/","title":{"rendered":"Nr 16 2023"},"content":{"rendered":"\n

En f\u00f6r de flesta ok\u00e4nd Orionnebulosa<\/h2>\n\n\n\n
\"\"<\/a><\/figure>\n\n\n\n

H\u00e4rom kv\u00e4llen kunde Hans Hilderfors<\/strong> bara inte l\u00e5ta bli: Han M\u00c5STE dokumentera Sh2-263 och vdB 38, en r\u00f6d emissions- respektive bl\u00e5 reflektionsnebulosa vid \u00f6vre delen av Orion. Nebulosan kallas ibland f\u00f6r \u201dThe Moldy Strawberry\u201d (Den m\u00f6gliga jordgubben).<\/p>\n\n\n\n

– Det \u00e4r den centrala ljusa bl\u00e5vita stj\u00e4rnan, HD 34989 (mag 5,8), som belyser gaserna i nebulosan. Den r\u00f6da delen lyser genom emission fr\u00e5n exciterade v\u00e4teatomer (H\u03b1) och den bl\u00e5a genom reflektion av det bl\u00e5aktiga stj\u00e4rnljuset.<\/p>\n\n\n\n

Beteckningen vdB komer fr\u00e5n namnet Sidney Van den Bergh<\/strong> (1929 – ), en holl\u00e4ndsk-kanadensisk astronom som 1966 gjorde en katalog \u00f6ver sammanlagt 158 olika reflektionsnebulosor.<\/p>\n\n\n\n

* Bilden \u00e4r uppbyggd via <\/strong>exponering genom tv\u00e5 filter, ett H\u03b1- (r\u00f6tt) respektive ett B- (bl\u00e5tt) filter.<\/p>\n\n\n\n

* H\u03b1-filtret \u00e4r ett smalbandsfilter<\/strong> som maskerar merparten av ljusf\u00f6roreningarna i Malm\u00f6.<\/p>\n\n\n\n

– Detta fungerar f\u00f6r emissionsnebulosan (den r\u00f6da). Reflektionsnebulosan d\u00e4remot kr\u00e4ver ett bredbandsfilter B som d\u00e5 tyv\u00e4rr ocks\u00e5 f\u00e5ngar ljusf\u00f6roreningarna och v\u00e4sentligt f\u00f6rsv\u00e5rar m\u00f6jligheten att f\u00e5 bra bild fr\u00e5n Malm\u00f6. M\u00e5nga exponeringar hj\u00e4lper till viss del.<\/p>\n\n\n\n

Datum: 2023-02-18, Malm\u00f6.<\/p>\n\n\n\n

Optik: Refraktor 130 f\/4,5.<\/p>\n\n\n\n

Kamera: Monokrom CMOS med filterhjul.<\/p>\n\n\n\n

Exponering: H\u03b1 18 x 300s   B 90 x 60s.   Summa: 3h<\/p>\n\n\n\n

Bildf\u00e4lt: 70′ x 53′<\/p>\n\n\n\n

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

En f\u00f6r de flesta ok\u00e4nd Orionnebulosa H\u00e4rom kv\u00e4llen kunde Hans Hilderfors bara inte l\u00e5ta bli: Han M\u00c5STE dokumentera Sh2-263 och vdB 38, en r\u00f6d emissions- respektive bl\u00e5 reflektionsnebulosa vid \u00f6vre delen av Orion. Nebulosan kallas ibland f\u00f6r \u201dThe Moldy Strawberry\u201d (Den m\u00f6gliga jordgubben). – Det \u00e4r den centrala ljusa bl\u00e5vita stj\u00e4rnan, HD 34989 (mag 5,8),… L\u00e4s mer »Nr 16 2023<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"rop_custom_images_group":[],"rop_custom_messages_group":[],"rop_publish_now":"initial","rop_publish_now_accounts":[],"rop_publish_now_history":[],"rop_publish_now_status":"pending","neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"","neve_meta_content_width":0,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":"","footnotes":""},"categories":[3],"tags":[],"_links":{"self":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts\/92666"}],"collection":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/comments?post=92666"}],"version-history":[{"count":5,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts\/92666\/revisions"}],"predecessor-version":[{"id":92685,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts\/92666\/revisions\/92685"}],"wp:attachment":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/media?parent=92666"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/categories?post=92666"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/tags?post=92666"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}