{"id":601,"date":"2014-08-24T22:57:18","date_gmt":"2014-08-24T20:57:18","guid":{"rendered":"http:\/\/freebook.fernglas-astronomie.de\/?page_id=601"},"modified":"2014-08-24T22:57:18","modified_gmt":"2014-08-24T20:57:18","slug":"virgo","status":"publish","type":"page","link":"http:\/\/freebook.fernglas-astronomie.de\/?page_id=601","title":{"rendered":"Virgo"},"content":{"rendered":"

The Virgin is the second largest constellation and easy to find thanks to the 1.0m<\/sup> bright Spica. The many galaxies in the 65 million light-years away Virgo Cluster are hard to find and a challenge even for an experienced observer. Owners of large telescopes can find 5\u00b0 north of \u03b3 Virginis also the brightest known quasar \u2013 it appears as a 13m<\/sup> star.<\/p>\n

RV Virginis<\/strong><\/em> is a Mira-type variable with an extremely short period \u2013 only around 145.5 days are between two maxima. During this time its brightness varies from 6.2 to 12.0m<\/sup>. As long as it is bright enough, you can find it 4.5\u00b0 southwest of Spica. Mira stars are old, red giant stars that pulsate. With the star\u2018s diameter, also its brightness changes.<\/p>\n

M 49<\/em><\/strong> is the second brightest elliptical galaxy of the Virgo Cluster. The 8 \u00d7 10 arcmin large galaxy is 8.4m bright and can be seen quite well in 7\u2009\u00d7\u200950 binoculars. Look for it 3.5\u00b0 southeast of the 4.9m<\/sup> bright \u03c1 Virginis. M\u200949 marks the center of the Virgo cloud, a subset of the Virgo cluster of galaxies.<\/p>\n

M 61<\/strong><\/em> is said to have been observed with averted vision in 7\u2009\u00d7\u200935 binoculars, when the sky is dark enough, and in a 10\u2009\u00d7\u200950 the brighter core of the six arcminutes large face-on galaxy is easily visible under good conditions \u2013 at least as blurry star. The galaxy is located 5\u00b0 north of \u03b7 Virginis and is 10.1m<\/sup> bright. At low magnification it appears only as a nebulous star, which does not make it obvious that you are looking at a 110,000 light-years wide and 36 million light-years distant barred spiral galaxy.<\/p>\n

M 84 and M 86<\/em><\/strong> form one of the better known galaxy pairs. They can be seen in a 10\u2009\u00d7\u200950 as two oval slices, each with about five minutes of arc in diameter. Look for them 5\u00b0 northwest of \u03c1 Virginis. M\u200984 is the western of the two galaxies and 39 million light-years away. It is an elliptical galaxy with a total luminosity of 9.1m<\/sup> and a diameter of 100,000 light-years. Thus, it is slightly smaller and more compact than M\u200986 (which is at 8.9m<\/sup> actually brighter), and because of this M\u200984 is easier to recognize, although it is dimmer. M\u200984 has no more direct companion galaxies. She\u2018s probably merged with them long ago, which would explain its large size.<\/p>\n

M\u200986<\/em><\/strong> is probably 53 million light-years away and has a diameter of 140,000-175,000 light-years. It is an intermediate form of an elliptical and a spiral galaxy. M\u200986 shows a blue shift, so it is actually moving towards us. M\u200984 and M\u200986 are 20 arc minutes apart, each of them has about 3,000 globular clusters.<\/p>\n

You may barely make out the dust belt in the equatorial plane of the edge-on galaxy in an 11\u2009\u00d7\u200980 binocular, which gave the Sombrero-Galaxy M 104<\/strong><\/em> its nickname. Under good conditions, smaller binoculars can show a nebula, which is brighter towards the center. The 8.0m<\/sup> bright galaxy is 8 \u00d7 3 arcmin large, and can be found 5.5\u00b0 northeast of \u03b7 Corvi. Thus, it is almost 20\u00b0 south of the Virgo Cluster. Whether it belongs to it or not, is unclear \u2013 older measurements gave a distance of 63 million light-years, today the distance is given as only 31 million light-years. In 1912, it was the first galaxy where a red shift was measured \u2013 eleven years before the distance of the Andromeda galaxy M\u200931 could be determined and thus the nature of the galaxies was clarified for the first time.<\/p>\n","protected":false},"excerpt":{"rendered":"

The Virgin is the second largest constellation and easy to find thanks to the 1.0m bright Spica. The many galaxies in the 65 million light-years away Virgo Cluster are hard to find and a challenge even for an experienced observer. Owners of large telescopes can find 5\u00b0 north of \u03b3 Virginis also the brightest known … Virgo<\/span> weiterlesen →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":591,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-601","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=\/wp\/v2\/pages\/601","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=601"}],"version-history":[{"count":1,"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=\/wp\/v2\/pages\/601\/revisions"}],"predecessor-version":[{"id":602,"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=\/wp\/v2\/pages\/601\/revisions\/602"}],"up":[{"embeddable":true,"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=\/wp\/v2\/pages\/591"}],"wp:attachment":[{"href":"http:\/\/freebook.fernglas-astronomie.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=601"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}