{"id":16816,"date":"2011-07-12T23:36:21","date_gmt":"2011-07-12T22:36:21","guid":{"rendered":"http:\/\/www.astb.se\/cassiopeiabloggen\/?p=16816"},"modified":"2011-07-12T23:36:21","modified_gmt":"2011-07-12T22:36:21","slug":"nr-169-2011","status":"publish","type":"post","link":"https:\/\/www.astb.se\/cassiopeiabloggen\/2011\/07\/12\/nr-169-2011\/","title":{"rendered":"Nr 169 2011"},"content":{"rendered":"<h2>Tycho p\u00e5 morgonkulan<\/h2>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1028.png\"><img decoding=\"async\" class=\"aligncenter size-full wp-image-16823\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1028.png\" alt=\"\" width=\"504\" height=\"231\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1028.png 504w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1028-300x137.png 300w\" sizes=\"(max-width: 504px) 100vw, 504px\" \/><\/a><\/p>\n<p>Jag m\u00e5ste erk\u00e4nna att vissa bilder fr\u00e5n den inre och yttre rymden fortfarande g\u00f6r mig paff &#8211; som denna studie av soluppg\u00e5ngen \u00f6ver Tycho-kratern p\u00e5 m\u00e5nen, dokumenterad av LRO\/LROC 10 juni i \u00e5r i sned vinkel.<\/p>\n<p>Toppen p\u00e5 centralberget ligger 2 km \u00f6ver kratergolvet, som i sin tur ligger 4700 m under randbergen.<\/p>\n<p>P\u00e5 bilden kan vi spana in klippor och stenblock 10 till 100-tals m stora. P\u00e5 toppen ser vi en rej\u00e4l men insul\u00e4r stenbumling, som i n\u00e4rbilden nedan framg\u00e5r \u00e4nnu b\u00e4ttre. Hur har den kommit dit? Vilken \u00e4r dess skapelsehistoria?<\/p>\n<p>Tycho \u00e4r en\u00a0 ung m\u00e5nkrater, skapad kanske f\u00f6r 110 miljoner \u00e5r sedan av en kraftig asteroidkrock. Kratern har \u00e4nnu inte slipats ner av alla de meteoriter och mikrometeoriter som hela tiden bombarderar m\u00e5nytan och som g\u00f6r att \u00e4ldre kratrar f\u00e5r en mera avslipad form.<\/p>\n<p>Fotocredit f\u00f6r dessa makal\u00f6sa bilder: NASA\/GSFC\/Arizona State University.<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1024.png\"><img decoding=\"async\" class=\"aligncenter size-full wp-image-16824\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1024.png\" alt=\"\" width=\"504\" height=\"504\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1024.png 504w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1024-150x150.png 150w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1024-300x300.png 300w\" sizes=\"(max-width: 504px) 100vw, 504px\" \/><\/a><\/p>\n<h2>Det finns dubbelstj\u00e4rnor&#8230;<\/h2>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/ogle_lmc_cep0227_300_196.jpg\"><img decoding=\"async\" width=\"150\" height=\"150\" class=\"alignleft size-thumbnail wp-image-16860\" style=\"width: 88px; height: 88px;\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/ogle_lmc_cep0227_300_196-150x150.jpg\" alt=\"\" \/><\/a>&#8230; och s\u00e5 finns det OGLE-LMC-CEP0227 i Stora Magellanska molnet, som hj\u00e4lpt astronomerna att l\u00f6sa upp en intrikat knut: Varf\u00f6r teorin om cepheidernas massor inte \u00f6verenst\u00e4mt med den g\u00e4ngse teorin om stj\u00e4rnors utveckling. Diskrepensen har legat p\u00e5 20 procent.<\/p>\n<p>Cepheider, som vi ju anv\u00e4nder som avst\u00e5ndsm\u00e4tare i det n\u00e4ra universum,\u00a0 tillh\u00f6r inte vanligheterna och det g\u00f6r inte bin\u00e4ra system heller, och cepheider i bin\u00e4ra system som f\u00f6rm\u00f6rkar varandra i v\u00e5r synriktning \u00e4r \u00e4nnu mera s\u00e4llsynta (inga observerade i Vintergatan so far). Men i v\u00e5r lilla granngalax hittades det unika stj\u00e4rnparet d\u00e4r stj\u00e4rnorna f\u00f6rm\u00f6rkar varandra (= ger oss m\u00f6jlighet fastst\u00e4lla massorna), s\u00e5 nu \u00e4r lyckan total. Och ordningen \u00e5terst\u00e4lld.<\/p>\n<p>Cepheiden har en period p\u00e5 3,8 jorddygn och paret snurrar runt varandra p\u00e5 310 dygn.<\/p>\n<p>M\u00e4tningen har utf\u00f6rts p\u00e5 La Silla i Chile av polska ESO-astronomer, bl a.<\/p>\n<h2>Neptunus f\u00f6delsedagsfiras av HST<\/h2>\n<p>Det g\u00e5r inte att komma ifr\u00e5n att Neptunus \u00e4r n\u00e5got s\u00e4rskilt. I samband med 1-\u00e5rsdagen &#8211; Neptunus har nu fullbordat sitt f\u00f6rsta solvarv efter uppt\u00e4ckten 23-24 september 1846 &#8211; l\u00e4t <a href=\"http:\/\/hubblesite.org\/newscenter\/archive\/releases\/2011\/19\/\">Hubble Space Telescope publicera n\u00e5gra bilder tagna med dess Wide Field Camera 3 dagarna 25-26 juni i \u00e5r<\/a>.<\/p>\n<p>Molnformationerna p\u00e5 norra och s\u00f6dra halvklotet best\u00e5r av metan i form av iskrtistaller.<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1-hubblesneptu-11.jpg\"><img decoding=\"async\" class=\"aligncenter size-medium wp-image-16843\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1-hubblesneptu-11-300x225.jpg\" alt=\"\" width=\"300\" height=\"225\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1-hubblesneptu-11-300x225.jpg 300w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/1-hubblesneptu-11.jpg 670w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p>N\u00e5gra fakta om Neptunus:<\/p>\n<p><strong>* Planeten \u00e4r i dag den yttersta<\/strong> i v\u00e5rt planetsystem, detta sedan Pluto degraderats till rollen av dv\u00e4rgplanet.<\/p>\n<p><strong>* Neptunus ligger 30 ggr <\/strong>l\u00e4ngre bort fr\u00e5n solen \u00e4n jorden, 4,5 miljarder km.<\/p>\n<p><strong>* Neptunus har \u00e5rstider<\/strong> som jorden, Neptunusaxeln lutar 29 grader mot planetens bana. Varje \u00e5rstid \u00e4r p\u00e5 cirka 40 \u00e5r&#8230; inte ens somrarna \u00e4r att f\u00f6redra!<\/p>\n<p><strong>* Neptunus \u00e4r en gasj\u00e4tte<\/strong> med en k\u00e4rna som alstrar v\u00e4rme.<br \/>\n<strong>* St\u00f6rningar i Uranus bana<\/strong> fick redan 1821 den franske astronomen <strong>Alexis Bouvard<\/strong> att diskutera p\u00e5verkan av en yttre planet.\u00a0 <strong>Urbain Le Verrier <\/strong>och <strong>John Couch Adams, <\/strong>fransman respektive britt, gjorde oberoende av varandra exakta positionsbest\u00e4mningar av den ok\u00e4nda planeten, som\u00a0 uppt\u00e4cktes 1846 av Berlin-astronomen <strong>Johan Gottfried Galle<\/strong>.<\/p>\n<p><strong>*\u00a0 Dock: Redan 1612 hade Galilei <\/strong>spanat in planeten men tog\u00a0 den f\u00f6r en &#8211; stj\u00e4rna. Galilei missade bussen!<\/p>\n<p><strong>*\u00a0 Neptunus omges av<\/strong> ett 30-tal K\u00c4NDA m\u00e5nar.<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/hubblesneptu.jpg\"><img decoding=\"async\" class=\"aligncenter size-full wp-image-16820\" title=\"N\u00e5gra av Neptunus-m\u00e5nrna i juni 2011. Foto: NASA\/ESA\/HST\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/hubblesneptu.jpg\" alt=\"\" width=\"300\" height=\"375\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/hubblesneptu.jpg 300w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/hubblesneptu-240x300.jpg 240w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<h2>Dagens citat<\/h2>\n<p>&#8220;Maybe this world is another planet&#8217;s Hell.&#8221;<br \/>\n<strong>&#8211; Aldous Huxley<\/strong><\/p>\n<h2>Next stop G\u00f6teborg<\/h2>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/ad2011_banner_3001-16.jpg\"><img decoding=\"async\" class=\"aligncenter size-full wp-image-16838\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/ad2011_banner_3001-16.jpg\" alt=\"\" width=\"300\" height=\"149\" \/><\/a><\/p>\n<p>Fakta <a href=\"http:\/\/www.chalmers.se\/rss\/oso-sv\/astronomdagarna-2011\">finns h\u00e4r<\/a>!<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/oso-vit-web1-17.jpg\"><img decoding=\"async\" class=\"aligncenter size-full wp-image-16840\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/07\/oso-vit-web1-17.jpg\" alt=\"\" width=\"138\" height=\"138\" \/><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tycho p\u00e5 morgonkulan Jag m\u00e5ste erk\u00e4nna att vissa bilder fr\u00e5n den inre och yttre rymden fortfarande g\u00f6r mig paff &#8211; som denna studie av soluppg\u00e5ngen \u00f6ver Tycho-kratern p\u00e5 m\u00e5nen, dokumenterad av LRO\/LROC 10 juni i \u00e5r i sned vinkel. Toppen p\u00e5 centralberget ligger 2 km \u00f6ver kratergolvet, som i sin tur ligger 4700 m under&hellip;&nbsp;<a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/2011\/07\/12\/nr-169-2011\/\" rel=\"bookmark\">L\u00e4s mer &raquo;<span class=\"screen-reader-text\">Nr 169 2011<\/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\/16816"}],"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=16816"}],"version-history":[{"count":38,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts\/16816\/revisions"}],"predecessor-version":[{"id":16863,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts\/16816\/revisions\/16863"}],"wp:attachment":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/media?parent=16816"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/categories?post=16816"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/tags?post=16816"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}