{"id":2395,"date":"2017-07-27T11:37:13","date_gmt":"2017-07-27T10:37:13","guid":{"rendered":"http:\/\/www.popastro.com\/main_spa1\/planetary\/?page_id=2395"},"modified":"2018-01-20T14:38:26","modified_gmt":"2018-01-20T14:38:26","slug":"observing-mercury","status":"publish","type":"page","link":"https:\/\/www.popastro.com\/planetary\/observing-mercury\/","title":{"rendered":"Observing Mercury"},"content":{"rendered":"<p>It is only comparatively recently that much was discovered concerning the true nature of this mysterious little world.<\/p>\n<p>It was long believed that Mercury spun once on it\u2019s axis in the same time as it took to make one revolution of the Sun (88 Earth days) but radar investigations have established a correct value of just over 58 days.<\/p>\n<p>This mistake was not really surprising as through the telescope, Mercury is very difficult to observe as the \u2018messenger of the gods\u2019 never strays further than 28\u00b0 away from the Sun and has a maximum apparent diameter of only 13 seconds of arc.<\/p>\n<p>Thus when a naked-eye object, Mercury is always low down and a clear horizon is necessary to see the planet in the dawn or dusk sky. For observers in the northern hemisphere, favourable elongations take place during the spring for evening observations and autumn for morning views but it is worth trying to locate Mercury at one of it\u2019s less favourable elongations during the year.<\/p>\n<p>Mercury is best seen through the telescope against a bright sky. Little will be seen apart from the phase but it is always a thrill to glimpse this elusive world for one\u2019s self.<\/p>\n<p>Full details concerning the current visibility of Mercury are given in \u201cSkyDiary\u201d in Popular Astronomy magazine.<\/p>\n<p><span style=\"color: #ff0000;\"><strong>Warning: When observing Mercury with a telescope or binoculars, only attempt to do so when the whole of the Sun\u2019s disk is below the horizon. As Mercury lies close to the Sun in the sky, there could be a danger of getting the Sun in the view. This could result in eye damage, or loss of eyesight.<\/strong><\/span><\/p>\n<h3>The Phases of Mercury<\/h3>\n<figure id=\"attachment_2482\" aria-describedby=\"caption-attachment-2482\" style=\"width: 519px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-2482\" src=\"https:\/\/www.popastro.com\/planetary\/wp-content\/uploads\/sites\/10\/2018\/01\/phases.gif\" alt=\"Phases of Mercury\" width=\"519\" height=\"414\" \/><figcaption id=\"caption-attachment-2482\" class=\"wp-caption-text\">Phases of Mercury<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>It is only comparatively recently that much was discovered concerning the true nature of this mysterious little world. It was long believed that Mercury spun once on it\u2019s axis in the same time as it took to make one revolution<a class=\"more-link\" href=\"https:\/\/www.popastro.com\/planetary\/observing-mercury\/\"><span>Read more<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_monsterinsights_skip_tracking":false,"footnotes":""},"categories":[],"tags":[],"class_list":["post-2395","page","type-page","status-publish","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.3 - aioseo.com -->\n\t<meta name=\"description\" content=\"It is only comparatively recently that much was discovered concerning the true nature of this mysterious little world. 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