Ekuinoks: Pabidaan ralatan

2 bita ditambahkan ,  5 bulan yang lalu
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[[File:Sun at moment of spring equinox 2019.jpg|thumb|Matahari pas tajadianya [[ekuinoks Maret]] di tahun 2019, haratan bagian tangah cakram matahari tatamu lawan [[ekuator langit]] (garis imajiner di [[bola langit]] diatas [[ekuator]] bumi) matam salatan ka utara.]]
 
'''Ekuinoks''' marupakan fenomena pas [[ekuator langit]] lawan [[ekuator]] [[bumi]] malewati pusat geometris matan cakram [[matahari]].<ref name="USNO FAQ">{{cite web |url=https://aa.usno.navy.mil/faq/docs/equinoxes.php |title=Equinoxes |date=14 June 2019 |work=Astronomical Information Center |publisher=[[United States Naval Observatory]] |archive-url=https://web.archive.org/web/20190525103847/https://aa.usno.navy.mil/faq/docs/equinoxes.php|archive-date=25 May 2019 |url-status=live |access-date=9 July 2019 |quote=On the day of an equinox, the geometric center of the Sun's disk crosses the equator, and this point is above the horizon for 12&nbsp;hours everywhere on the Earth. However, the Sun is not simply a geometric point. Sunrise is defined as the instant when the leading edge of the Sun's disk becomes visible on the horizon, whereas sunset is the instant when the trailing edge of the disk disappears below the horizon. These are the moments of first and last direct sunlight. At these times the center of the disk is below the horizon. Furthermore, atmospheric refraction causes the Sun's disk to appear higher in the sky than it would if the Earth had no atmosphere. Thus, in the morning the upper edge of the disk is visible for several minutes before the geometric edge of the disk reaches the horizon. Similarly, in the evening the upper edge of the disk disappears several minutes after the geometric disk has passed below the horizon. The times of sunrise and sunset in almanacs are calculated for the normal atmospheric refraction of 34&nbsp;minutes of arc and a [[semidiameter]] of 16&nbsp;minutes of arc for the disk. Therefore, at the tabulated time the geometric center of the Sun is actually 50&nbsp;minutes of arc below a regular and unobstructed horizon for an observer on the surface of the Earth in a level region}}</ref><ref>{{cite web |url=https://www.esrl.noaa.gov/gmd/grad/solcalc/glossary.html#equinox |title=ESRL Global Monitoring Division - Global Radiation Group |publisher=U.S. Department of Commerce |department=[[NOAA]] |website=www.esrl.noaa.gov |language=EN-US |access-date=9 July 2019}}</ref> Fenomena ngini tajadi dua kali satiap tahunnya, yaitu, pas sakitar [[Ekuinoks Maret|20 Maret]] wan [[Ekuinoks September|23 September]]. Kawa disambat, bahwa kajadian ngini marupakan fenomena haratan tangah matahari kawa taitihi baandak [[Zenit|pas di atas ekuator]]
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