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Daylight hours in Río Gallegos

Río Gallegos gets 16h 37m of daylight on its longest day in December, and 7h 50m on its shortest in June — a difference of 8h 48m across the year.

How fast the days change

Around 12 March, Río Gallegos gains or loses about 4.0 minutes of daylight every day.

That is quick enough to notice week to week, which is why spring seems to arrive all at once this far from the equator.

Sunrise and sunset by month

On the 15th of each month, in America/Argentina/Rio_Gallegos local time, daylight saving included.

Sunrise, sunset and day length by month.
MonthSunriseSunsetDaylightSolar noon
January 05:43 21:49 16h 06m 13:46
February 06:40 21:02 14h 22m 13:51
March 07:30 20:01 12h 31m 13:45
April 08:22 18:51 10h 29m 13:37
May 09:10 17:56 8h 47m 13:33
June 09:42 17:32 7h 50m 13:37
July 09:35 17:50 8h 15m 13:43
August 08:48 18:34 9h 46m 13:41
September 07:41 19:23 11h 42m 13:32
October 06:32 20:12 13h 40m 13:22
November 05:34 21:08 15h 34m 13:21
December 05:13 21:50 16h 37m 13:32

Solstices and equinoxes

DateSunriseSunsetDaylight
March equinox 20 Mar 07:39 19:49 12h 11m
June solstice 21 Jun 09:44 17:33 7h 48m
September equinox 22 Sep 07:25 19:34 12h 09m
December solstice 21 Dec 05:15 21:54 16h 40m

The equinoxes give almost exactly twelve hours of daylight everywhere on earth — "almost" because sunrise is defined by the sun's upper edge rather than its centre, and the atmosphere bends its light over the horizon before it has really arrived. Both lengthen the day by a few minutes.

Other cities in Argentina

Assumptions

  • Sea-level horizon. Hills, mountains and buildings all delay sunrise and bring sunset forward, sometimes by a lot in a valley.
  • Standard refraction. Sunrise is taken at −0.833°, allowing for the sun's disc and average atmospheric bending. Unusual air conditions shift it by a minute or two.
  • Local clock time, with daylight saving applied from the IANA timezone database.

Full methodology, sources and known limitations