{"id":24377,"date":"2023-02-26T19:00:34","date_gmt":"2023-02-26T18:00:34","guid":{"rendered":"https:\/\/www.sciencefocus.com\/?p=135163"},"modified":"2023-02-26T20:35:12","modified_gmt":"2023-02-26T19:35:12","slug":"with-two-week-nights-moon-colonisers-will-have-a-seriously-weird-daily-cycle","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcsciencefocus\/rss_feed\/with-two-week-nights-moon-colonisers-will-have-a-seriously-weird-daily-cycle\/","title":{"rendered":"With two-week nights, Moon colonisers will have a seriously weird daily cycle"},"content":{"rendered":"

When Artemis 3 lifts off, we’ll be one step closer… <\/p>

By Dr Alastair Gunn\n \t\t<\/p>

Published: Sunday, 26 February 2023 at 12:00 am<\/p>

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Yes, anyone living\u00a0on\u00a0the Moon<\/a> will experience night and day, but a lunar day and night would last almost an entire Earth month.<\/p>\n

Earth\u2019s gravity<\/a> causes the Moon to elongate slightly\u00a0on the sides nearest and farthest from us. The gravitational forces acting differently on the near and far\u00a0side of the Moon\u2019s \u2018bulge\u2019 creates a torque\u00a0that\u00a0acts to alter the Moon\u2019s rotational period so that it matches its orbit period. This is known as \u2018tidal locking<\/a>\u2019.<\/p>\n

Because the Moon spins in the same time as it orbits Earth, it only ever presents the same face to\u00a0us.\u00a0But\u00a0even though the Moon is \u2018tidally locked\u2019 to Earth, it\u2019s still rotating with respect to the Sun. Its rotation period is 29 days, 12 hours and 44 minutes (also the length of the \u2018lunar month\u2019 on Earth). So,\u00a0a lunar colonist would\u00a0experience about two weeks of daylight, followed by about two weeks of night.<\/p>\n

Of course, from the nearside of the Moon, Earth appears to stay in exactly the same position in the sky while the stars rise and set \u2014 although Earth\u2019s exact position depends on where you are on the Moon. The phase of Earth will change,\u00a0just\u00a0like the Moon\u2019s does, over a lunar month, but Earth itself will be seen spinning once in a little over 24 hours.<\/p>\n

Earth would be fully illuminated (a\u00a0\u2018full Earth\u2019) in the middle of the lunar night, while at \u2018new Earth\u2019 it would be almost hidden in the glare of the Sun<\/a> and showing its unlit, night-time hemisphere. Since Earth is about four times the size of the Moon, solar eclipses visible on the Moon last much longer than on Earth. Every time\u00a0people on\u00a0Earth see a total lunar eclipse,\u00a0anyone living on the Moon would see a total solar eclipse.<\/p>\n

Read more:<\/strong><\/p>\n