{"id":21532,"date":"2021-08-04T18:41:26","date_gmt":"2021-08-04T18:41:26","guid":{"rendered":"https:\/\/www.skyatnightmagazine.com\/?p=98907"},"modified":"2021-08-04T19:02:10","modified_gmt":"2021-08-04T19:02:10","slug":"a-guide-to-the-moons-pythagoras-crater","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/rss_feed\/a-guide-to-the-moons-pythagoras-crater\/","title":{"rendered":"A guide to the Moon\u2019s Pythagoras Crater"},"content":{"rendered":"

<\/p>

By Pete Lawrence\n \t\t<\/p>

Published: Wednesday, 04 August 2021 at 12:00 am<\/p>

\n\n

Pythagoras is a magnificent example of a lunar crater. It\u2019s 129km in diameter and fairly close to the Moon\u2019s northwest limb, and as a consequence it appears rather foreshortened to us on Earth, changing shape due to the effects of lunar libration<\/a>.<\/span><\/p>\n

The crater\u2019s rim is surrounded by sloping ramparts rising gently above their surroundings. It appears to terrace its way down to a <\/span>relatively flat floor approximately<\/span> 4.8km below.<\/span><\/p>\n

Apart from the obvious central mountain complex that lies at the centre <\/span>of the crater, the floor shows littl<\/span>e detail until the illumination becomes oblique.<\/span><\/p>\n

When that happens, you should be able to see a series of low-altitude hills, giving the floor some texture.<\/span><\/p>\n

For more lunar observing advice, read our guide on how to observe the Moon<\/a> and the best features on the Moon<\/a>.<\/strong><\/em><\/p>\n

\""Three\"<\/div>
Three peaks dominate Pythagoras, and they\u2019re a useful aid to identifying the crater. Credit: Pete Lawrence<\/span><\/figcaption><\/div>\n

Facts about Pythagoras Crater<\/span><\/strong><\/h1>\n
  • Size:<\/b> Approximately 129km across<\/li>\n
  • Longitude\/Latitude:<\/b> 63.0\u00baW, 63.7\u00baN<\/li>\n
  • Age:<\/b> 1.1-3.2 billion years<\/li>\n
  • Best time to see:<\/b> Five days after first quarter or four days after last quarter (6-8 July and 19-21 July)<\/li>\n
  • Minimum observing equipment: <\/b>10x binoculars<\/li>\n<\/ul>

    \u00a0<\/p>\n

    The central mountains are particularly striking and extremely useful for quickly identifying Pythagoras.<\/span><\/p>\n

    As is often the case with features closer to the limb, it\u2019s an area in which it is easy to lose your way, but those Pythagorean peaks act as solid navigational beacons.<\/span><\/p>\n

    There are three peaks visible, rising to impressive heights estimated to be around 3km above the crater floor. <\/span><\/p>\n

    Despite providing such stunning signposting when the lighting is right, Pythagoras is surprisingly easy to lose when the Sun is high in the crater\u2019s sky.<\/span><\/p>\n

    \""Crater\"<\/div>
    Crater Pythagoras by Graeme Coates, Standlake, Oxfordshire, UK. Equipment: Orion Optics SPX350, 2x barlow, ZWO ASI120MM, Astronomik 742nm Near IR filter.<\/span><\/figcaption><\/div>\n

    At such times, the best way to locate it is to realise that it forms a right angled triangle with the beautiful semi-circular feature known as Sinus Iridum and the dark floored, circular Plato crater. <\/span><\/p>\n

    Once you realise that Sinus Iridum sits at the right angle of this triangle, finding Pythagoras under full illumination is remarkably straightforward.<\/span><\/p>\n

    \""Crater\"<\/div>
    Crater Pythagoras by John Brady, UK. Equipment: Skywatcher 200p, MK41 mono CCD.<\/span><\/figcaption><\/div>\n

    Libration plays a big part in the crater\u2019s appearance and when in its least favourable position, Pythagoras sits virtually on the Moon\u2019s limb, giving us a sideways view.<\/span><\/p>\n

    Even when well placed, we are presented with a good view of its western rim terraces, but those to the east appear heavily foreshortened and difficult to discern. <\/span><\/p>\n

    The most prominent features that lie nearby are fairly rugged and irregular in shape.<\/span><\/p>\n

    To the south is 144km crater Babbage, <\/span>the irregular rim of which contains<\/span> the more defined forms of Babbage A (26km) and Babbage C (14km) the latter lying right at the centre of Babbage itself.<\/span><\/p>\n

    To the northeast is the curious form of Anaximander (68km). <\/span>The parent crater here is difficult<\/span> to see as its floor is conjoined with Anaximander D (92km), and Anaximander B (78km). <\/span><\/p>\n

    \n
    \""Pythagoras\"<\/div>
    Pythagoras with C14 Edge by Avani Soares, Canoas, Brazil. Equipment: C14 Edge, ASI 290, IR 685<\/span><\/figcaption><\/div>\n
    ","protected":false},"excerpt":{"rendered":"

    By Pete Lawrence Published: Wednesday, 04 August 2021 at 12:00 am Pythagoras is a magnificent example of a lunar crater. It\u2019s 129km in diameter and fairly close to the Moon\u2019s northwest limb, and as a consequence it appears rather foreshortened to us on Earth, changing shape due to the effects of lunar libration. The crater\u2019s […]<\/p>\n","protected":false},"author":24,"featured_media":0,"template":"","categories":[34],"acf":{"readingTimeMinutes":"3"},"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":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":"By Pete Lawrence Published: Wednesday, 04 August 2021 at 12:00 am Pythagoras is a magnificent example of a lunar crater. It\u2019s 129km in diameter and fairly close to the Moon\u2019s northwest limb, and as a consequence it appears rather foreshortened to us on Earth, changing shape due to the effects of lunar libration. The crater\u2019s…","_links":{"self":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/rss_feed\/21532"}],"collection":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/rss_feed"}],"about":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/types\/rss_feed"}],"author":[{"embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/users\/24"}],"wp:attachment":[{"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/media?parent=21532"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/c01.purpledshub.com\/bbcskyatnight\/wp-json\/wp\/v2\/categories?post=21532"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}